Move crow to its own repo
diff --git a/crow/include/crow.h b/crow/include/crow.h
new file mode 100644
index 0000000..9a0c22e
--- /dev/null
+++ b/crow/include/crow.h
@@ -0,0 +1,23 @@
+#pragma once
+#include "crow/query_string.h"
+#include "crow/http_parser_merged.h"
+#include "crow/ci_map.h"
+#include "crow/TinySHA1.hpp"
+#include "crow/settings.h"
+#include "crow/socket_adaptors.h"
+#include "crow/json.h"
+#include "crow/mustache.h"
+#include "crow/logging.h"
+#include "crow/dumb_timer_queue.h"
+#include "crow/utility.h"
+#include "crow/common.h"
+#include "crow/http_request.h"
+#include "crow/websocket.h"
+#include "crow/parser.h"
+#include "crow/http_response.h"
+#include "crow/middleware.h"
+#include "crow/routing.h"
+#include "crow/middleware_context.h"
+#include "crow/http_connection.h"
+#include "crow/http_server.h"
+#include "crow/app.h"
diff --git a/crow/include/crow/TinySHA1.hpp b/crow/include/crow/TinySHA1.hpp
new file mode 100644
index 0000000..a8d7bc8
--- /dev/null
+++ b/crow/include/crow/TinySHA1.hpp
@@ -0,0 +1,195 @@
+/*
+ *
+ * TinySHA1 - a header only implementation of the SHA1 algorithm in C++. Based
+ * on the implementation in boost::uuid::details.
+ *
+ * SHA1 Wikipedia Page: http://en.wikipedia.org/wiki/SHA-1
+ *
+ * Copyright (c) 2012-22 SAURAV MOHAPATRA <mohaps@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef _TINY_SHA1_HPP_
+#define _TINY_SHA1_HPP_
+#include <stdint.h>
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+namespace sha1 {
+class SHA1 {
+ public:
+  typedef uint32_t digest32_t[5];
+  typedef uint8_t digest8_t[20];
+  inline static uint32_t LeftRotate(uint32_t value, size_t count) {
+    return (value << count) ^ (value >> (32 - count));
+  }
+  SHA1() { reset(); }
+  virtual ~SHA1() {}
+  SHA1(const SHA1& s) { *this = s; }
+  const SHA1& operator=(const SHA1& s) {
+    memcpy(m_digest, s.m_digest, 5 * sizeof(uint32_t));
+    memcpy(m_block, s.m_block, 64);
+    m_blockByteIndex = s.m_blockByteIndex;
+    m_byteCount = s.m_byteCount;
+    return *this;
+  }
+  SHA1& reset() {
+    m_digest[0] = 0x67452301;
+    m_digest[1] = 0xEFCDAB89;
+    m_digest[2] = 0x98BADCFE;
+    m_digest[3] = 0x10325476;
+    m_digest[4] = 0xC3D2E1F0;
+    m_blockByteIndex = 0;
+    m_byteCount = 0;
+    return *this;
+  }
+  SHA1& processByte(uint8_t octet) {
+    this->m_block[this->m_blockByteIndex++] = octet;
+    ++this->m_byteCount;
+    if (m_blockByteIndex == 64) {
+      this->m_blockByteIndex = 0;
+      processBlock();
+    }
+    return *this;
+  }
+  SHA1& processBlock(const void* const start, const void* const end) {
+    const uint8_t* begin = static_cast<const uint8_t*>(start);
+    const uint8_t* finish = static_cast<const uint8_t*>(end);
+    while (begin != finish) {
+      processByte(*begin);
+      begin++;
+    }
+    return *this;
+  }
+  SHA1& processBytes(const void* const data, size_t len) {
+    const uint8_t* block = static_cast<const uint8_t*>(data);
+    processBlock(block, block + len);
+    return *this;
+  }
+  const uint32_t* getDigest(digest32_t digest) {
+    size_t bitCount = this->m_byteCount * 8;
+    processByte(0x80);
+    if (this->m_blockByteIndex > 56) {
+      while (m_blockByteIndex != 0) {
+        processByte(0);
+      }
+      while (m_blockByteIndex < 56) {
+        processByte(0);
+      }
+    } else {
+      while (m_blockByteIndex < 56) {
+        processByte(0);
+      }
+    }
+    processByte(0);
+    processByte(0);
+    processByte(0);
+    processByte(0);
+    processByte(static_cast<unsigned char>((bitCount >> 24) & 0xFF));
+    processByte(static_cast<unsigned char>((bitCount >> 16) & 0xFF));
+    processByte(static_cast<unsigned char>((bitCount >> 8) & 0xFF));
+    processByte(static_cast<unsigned char>((bitCount)&0xFF));
+
+    memcpy(digest, m_digest, 5 * sizeof(uint32_t));
+    return digest;
+  }
+  const uint8_t* getDigestBytes(digest8_t digest) {
+    digest32_t d32;
+    getDigest(d32);
+    size_t di = 0;
+    digest[di++] = ((d32[0] >> 24) & 0xFF);
+    digest[di++] = ((d32[0] >> 16) & 0xFF);
+    digest[di++] = ((d32[0] >> 8) & 0xFF);
+    digest[di++] = ((d32[0]) & 0xFF);
+
+    digest[di++] = ((d32[1] >> 24) & 0xFF);
+    digest[di++] = ((d32[1] >> 16) & 0xFF);
+    digest[di++] = ((d32[1] >> 8) & 0xFF);
+    digest[di++] = ((d32[1]) & 0xFF);
+
+    digest[di++] = ((d32[2] >> 24) & 0xFF);
+    digest[di++] = ((d32[2] >> 16) & 0xFF);
+    digest[di++] = ((d32[2] >> 8) & 0xFF);
+    digest[di++] = ((d32[2]) & 0xFF);
+
+    digest[di++] = ((d32[3] >> 24) & 0xFF);
+    digest[di++] = ((d32[3] >> 16) & 0xFF);
+    digest[di++] = ((d32[3] >> 8) & 0xFF);
+    digest[di++] = ((d32[3]) & 0xFF);
+
+    digest[di++] = ((d32[4] >> 24) & 0xFF);
+    digest[di++] = ((d32[4] >> 16) & 0xFF);
+    digest[di++] = ((d32[4] >> 8) & 0xFF);
+    digest[di++] = ((d32[4]) & 0xFF);
+    return digest;
+  }
+
+ protected:
+  void processBlock() {
+    uint32_t w[80];
+    for (size_t i = 0; i < 16; i++) {
+      w[i] = (m_block[i * 4 + 0] << 24);
+      w[i] |= (m_block[i * 4 + 1] << 16);
+      w[i] |= (m_block[i * 4 + 2] << 8);
+      w[i] |= (m_block[i * 4 + 3]);
+    }
+    for (size_t i = 16; i < 80; i++) {
+      w[i] = LeftRotate((w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16]), 1);
+    }
+
+    uint32_t a = m_digest[0];
+    uint32_t b = m_digest[1];
+    uint32_t c = m_digest[2];
+    uint32_t d = m_digest[3];
+    uint32_t e = m_digest[4];
+
+    for (std::size_t i = 0; i < 80; ++i) {
+      uint32_t f = 0;
+      uint32_t k = 0;
+
+      if (i < 20) {
+        f = (b & c) | (~b & d);
+        k = 0x5A827999;
+      } else if (i < 40) {
+        f = b ^ c ^ d;
+        k = 0x6ED9EBA1;
+      } else if (i < 60) {
+        f = (b & c) | (b & d) | (c & d);
+        k = 0x8F1BBCDC;
+      } else {
+        f = b ^ c ^ d;
+        k = 0xCA62C1D6;
+      }
+      uint32_t temp = LeftRotate(a, 5) + f + e + k + w[i];
+      e = d;
+      d = c;
+      c = LeftRotate(b, 30);
+      b = a;
+      a = temp;
+    }
+
+    m_digest[0] += a;
+    m_digest[1] += b;
+    m_digest[2] += c;
+    m_digest[3] += d;
+    m_digest[4] += e;
+  }
+
+ private:
+  digest32_t m_digest;
+  uint8_t m_block[64];
+  size_t m_blockByteIndex;
+  size_t m_byteCount;
+};
+}
+#endif
diff --git a/crow/include/crow/app.h b/crow/include/crow/app.h
new file mode 100644
index 0000000..40b759c
--- /dev/null
+++ b/crow/include/crow/app.h
@@ -0,0 +1,209 @@
+#pragma once
+
+#include <chrono>
+#include <cstdint>
+#include <functional>
+#include <future>
+#include <memory>
+#include <string>
+#include <thread>
+#include <type_traits>
+
+#include "crow/http_request.h"
+#include "crow/http_server.h"
+#include "crow/logging.h"
+#include "crow/middleware_context.h"
+#include "crow/routing.h"
+#include "crow/settings.h"
+#include "crow/utility.h"
+
+#ifdef CROW_MSVC_WORKAROUND
+#define CROW_ROUTE(app, url) app.route_dynamic(url)
+#else
+#define CROW_ROUTE(app, url) \
+  app.route<crow::black_magic::get_parameter_tag(url)>(url)
+#endif
+
+namespace crow {
+#ifdef CROW_ENABLE_SSL
+using ssl_context_t = boost::asio::ssl::context;
+#endif
+template <typename... Middlewares>
+class Crow {
+ public:
+  using self_t = Crow;
+  using server_t = Server<Crow, SocketAdaptor, Middlewares...>;
+#ifdef CROW_ENABLE_SSL
+  using ssl_server_t = Server<Crow, SSLAdaptor, Middlewares...>;
+#endif
+  Crow() {}
+
+  template <typename Adaptor>
+  void handle_upgrade(const request& req, response& res, Adaptor&& adaptor) {
+    router_.handle_upgrade(req, res, adaptor);
+  }
+
+  void handle(const request& req, response& res) { router_.handle(req, res); }
+
+  DynamicRule& route_dynamic(std::string&& rule) {
+    return router_.new_rule_dynamic(std::move(rule));
+  }
+
+  template <uint64_t Tag>
+  auto route(std::string&& rule) -> typename std::result_of<
+      decltype (&Router::new_rule_tagged<Tag>)(Router, std::string&&)>::type {
+    return router_.new_rule_tagged<Tag>(std::move(rule));
+  }
+
+  self_t& port(std::uint16_t port) {
+    port_ = port;
+    return *this;
+  }
+
+  self_t& bindaddr(std::string bindaddr) {
+    bindaddr_ = bindaddr;
+    return *this;
+  }
+
+  self_t& multithreaded() {
+    return concurrency(std::thread::hardware_concurrency());
+  }
+
+  self_t& concurrency(std::uint16_t concurrency) {
+    if (concurrency < 1) concurrency = 1;
+    concurrency_ = concurrency;
+    return *this;
+  }
+
+  void validate() { router_.validate(); }
+
+  void run() {
+    validate();
+#ifdef CROW_ENABLE_SSL
+    if (use_ssl_) {
+      ssl_server_ = std::move(std::unique_ptr<ssl_server_t>(new ssl_server_t(
+          this, bindaddr_, port_, &middlewares_, concurrency_, &ssl_context_)));
+      ssl_server_->set_tick_function(tick_interval_, tick_function_);
+      ssl_server_->run();
+    } else
+#endif
+    {
+      server_ = std::move(std::unique_ptr<server_t>(new server_t(
+          this, bindaddr_, port_, &middlewares_, concurrency_, nullptr)));
+      server_->set_tick_function(tick_interval_, tick_function_);
+      server_->run();
+    }
+  }
+
+  void stop() {
+#ifdef CROW_ENABLE_SSL
+    if (use_ssl_) {
+      ssl_server_->stop();
+    } else
+#endif
+    {
+      server_->stop();
+    }
+  }
+
+  void debug_print() {
+    CROW_LOG_DEBUG << "Routing:";
+    router_.debug_print();
+  }
+
+#ifdef CROW_ENABLE_SSL
+  self_t& ssl_file(const std::string& crt_filename,
+                   const std::string& key_filename) {
+    use_ssl_ = true;
+    ssl_context_.set_verify_mode(boost::asio::ssl::verify_peer);
+    ssl_context_.use_certificate_file(crt_filename, ssl_context_t::pem);
+    ssl_context_.use_private_key_file(key_filename, ssl_context_t::pem);
+    ssl_context_.set_options(boost::asio::ssl::context::default_workarounds |
+                             boost::asio::ssl::context::no_sslv2 |
+                             boost::asio::ssl::context::no_sslv3);
+    return *this;
+  }
+
+  self_t& ssl_file(const std::string& pem_filename) {
+    use_ssl_ = true;
+    ssl_context_.set_verify_mode(boost::asio::ssl::verify_peer);
+    ssl_context_.load_verify_file(pem_filename);
+    ssl_context_.set_options(boost::asio::ssl::context::default_workarounds |
+                             boost::asio::ssl::context::no_sslv2 |
+                             boost::asio::ssl::context::no_sslv3);
+    return *this;
+  }
+
+  self_t& ssl(boost::asio::ssl::context&& ctx) {
+    use_ssl_ = true;
+    ssl_context_ = std::move(ctx);
+    return *this;
+  }
+
+  bool use_ssl_{false};
+  ssl_context_t ssl_context_{boost::asio::ssl::context::sslv23};
+
+#else
+  template <typename T, typename... Remain>
+  self_t& ssl_file(T&&, Remain&&...) {
+    // We can't call .ssl() member function unless CROW_ENABLE_SSL is defined.
+    static_assert(
+        // make static_assert dependent to T; always false
+        std::is_base_of<T, void>::value,
+        "Define CROW_ENABLE_SSL to enable ssl support.");
+    return *this;
+  }
+
+  template <typename T>
+  self_t& ssl(T&&) {
+    // We can't call .ssl() member function unless CROW_ENABLE_SSL is defined.
+    static_assert(
+        // make static_assert dependent to T; always false
+        std::is_base_of<T, void>::value,
+        "Define CROW_ENABLE_SSL to enable ssl support.");
+    return *this;
+  }
+#endif
+
+  // middleware
+  using context_t = detail::context<Middlewares...>;
+  template <typename T>
+  typename T::context& get_context(const request& req) {
+    static_assert(black_magic::contains<T, Middlewares...>::value,
+                  "App doesn't have the specified middleware type.");
+    auto& ctx = *reinterpret_cast<context_t*>(req.middleware_context);
+    return ctx.template get<T>();
+  }
+
+  template <typename T>
+  T& get_middleware() {
+    return utility::get_element_by_type<T, Middlewares...>(middlewares_);
+  }
+
+  template <typename Duration, typename Func>
+  self_t& tick(Duration d, Func f) {
+    tick_interval_ = std::chrono::duration_cast<std::chrono::milliseconds>(d);
+    tick_function_ = f;
+    return *this;
+  }
+
+ private:
+  uint16_t port_ = 80;
+  uint16_t concurrency_ = 1;
+  std::string bindaddr_ = "0.0.0.0";
+  Router router_;
+
+  std::chrono::milliseconds tick_interval_;
+  std::function<void()> tick_function_;
+
+  std::tuple<Middlewares...> middlewares_;
+
+#ifdef CROW_ENABLE_SSL
+  std::unique_ptr<ssl_server_t> ssl_server_;
+#endif
+  std::unique_ptr<server_t> server_;
+};
+template <typename... Middlewares>
+using App = Crow<Middlewares...>;
+using SimpleApp = Crow<>;
+}
diff --git a/crow/include/crow/ci_map.h b/crow/include/crow/ci_map.h
new file mode 100644
index 0000000..b2021d3
--- /dev/null
+++ b/crow/include/crow/ci_map.h
@@ -0,0 +1,29 @@
+#pragma once
+
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/functional/hash.hpp>
+#include <unordered_map>
+
+namespace crow {
+struct ci_hash {
+  size_t operator()(const std::string& key) const {
+    std::size_t seed = 0;
+    std::locale locale;
+
+    for (auto c : key) {
+      boost::hash_combine(seed, std::toupper(c, locale));
+    }
+
+    return seed;
+  }
+};
+
+struct ci_key_eq {
+  bool operator()(const std::string& l, const std::string& r) const {
+    return boost::iequals(l, r);
+  }
+};
+
+using ci_map =
+    std::unordered_multimap<std::string, std::string, ci_hash, ci_key_eq>;
+}
diff --git a/crow/include/crow/common.h b/crow/include/crow/common.h
new file mode 100644
index 0000000..b2b68e3
--- /dev/null
+++ b/crow/include/crow/common.h
@@ -0,0 +1,133 @@
+#pragma once
+
+#include <iostream>
+#include <stdexcept>
+#include <string>
+#include <vector>
+#include "crow/utility.h"
+
+namespace crow {
+enum class HTTPMethod {
+#ifndef DELETE
+  DELETE = 0,
+  GET,
+  HEAD,
+  POST,
+  PUT,
+  CONNECT,
+  OPTIONS,
+  TRACE,
+#endif
+
+  Delete = 0,
+  Get,
+  Head,
+  Post,
+  Put,
+  Connect,
+  Options,
+  Trace,
+};
+
+inline std::string method_name(HTTPMethod method) {
+  switch (method) {
+    case HTTPMethod::Delete:
+      return "DELETE";
+    case HTTPMethod::Get:
+      return "GET";
+    case HTTPMethod::Head:
+      return "HEAD";
+    case HTTPMethod::Post:
+      return "POST";
+    case HTTPMethod::Put:
+      return "PUT";
+    case HTTPMethod::Connect:
+      return "CONNECT";
+    case HTTPMethod::Options:
+      return "OPTIONS";
+    case HTTPMethod::Trace:
+      return "TRACE";
+  }
+  return "invalid";
+}
+
+enum class ParamType {
+  INT,
+  UINT,
+  DOUBLE,
+  STRING,
+  PATH,
+
+  MAX
+};
+
+struct routing_params {
+  std::vector<int64_t> int_params;
+  std::vector<uint64_t> uint_params;
+  std::vector<double> double_params;
+  std::vector<std::string> string_params;
+
+  void debug_print() const {
+    std::cerr << "routing_params" << std::endl;
+    for (auto i : int_params) std::cerr << i << ", ";
+    std::cerr << std::endl;
+    for (auto i : uint_params) std::cerr << i << ", ";
+    std::cerr << std::endl;
+    for (auto i : double_params) std::cerr << i << ", ";
+    std::cerr << std::endl;
+    for (auto& i : string_params) std::cerr << i << ", ";
+    std::cerr << std::endl;
+  }
+
+  template <typename T>
+  T get(unsigned) const;
+};
+
+template <>
+inline int64_t routing_params::get<int64_t>(unsigned index) const {
+  return int_params[index];
+}
+
+template <>
+inline uint64_t routing_params::get<uint64_t>(unsigned index) const {
+  return uint_params[index];
+}
+
+template <>
+inline double routing_params::get<double>(unsigned index) const {
+  return double_params[index];
+}
+
+template <>
+inline std::string routing_params::get<std::string>(unsigned index) const {
+  return string_params[index];
+}
+}
+
+#ifndef CROW_MSVC_WORKAROUND
+constexpr crow::HTTPMethod operator"" _method(const char* str, size_t /*len*/) {
+  return crow::black_magic::is_equ_p(str, "GET", 3)
+             ? crow::HTTPMethod::Get
+             : crow::black_magic::is_equ_p(str, "DELETE", 6)
+                   ? crow::HTTPMethod::Delete
+                   : crow::black_magic::is_equ_p(str, "HEAD", 4)
+                         ? crow::HTTPMethod::Head
+                         : crow::black_magic::is_equ_p(str, "POST", 4)
+                               ? crow::HTTPMethod::Post
+                               : crow::black_magic::is_equ_p(str, "PUT", 3)
+                                     ? crow::HTTPMethod::Put
+                                     : crow::black_magic::is_equ_p(str,
+                                                                   "OPTIONS", 7)
+                                           ? crow::HTTPMethod::Options
+                                           : crow::black_magic::is_equ_p(
+                                                 str, "CONNECT", 7)
+                                                 ? crow::HTTPMethod::Connect
+                                                 : crow::black_magic::is_equ_p(
+                                                       str, "TRACE", 5)
+                                                       ? crow::HTTPMethod::Trace
+                                                       : throw std::
+                                                             runtime_error(
+                                                                 "invalid http "
+                                                                 "method");
+}
+#endif
diff --git a/crow/include/crow/dumb_timer_queue.h b/crow/include/crow/dumb_timer_queue.h
new file mode 100644
index 0000000..7a289dc
--- /dev/null
+++ b/crow/include/crow/dumb_timer_queue.h
@@ -0,0 +1,67 @@
+#pragma once
+
+#include <boost/asio.hpp>
+#include <chrono>
+#include <deque>
+#include <functional>
+#include <thread>
+
+#include "crow/logging.h"
+
+namespace crow {
+namespace detail {
+// fast timer queue for fixed tick value.
+class dumb_timer_queue {
+ public:
+  using key = std::pair<dumb_timer_queue*, int>;
+
+  void cancel(key& k) {
+    auto self = k.first;
+    k.first = nullptr;
+    if (!self) return;
+
+    unsigned int index = (unsigned int)(k.second - self->step_);
+    if (index < self->dq_.size()) self->dq_[index].second = nullptr;
+  }
+
+  key add(std::function<void()> f) {
+    dq_.emplace_back(std::chrono::steady_clock::now(), std::move(f));
+    int ret = step_ + dq_.size() - 1;
+
+    CROW_LOG_DEBUG << "timer add inside: " << this << ' ' << ret;
+    return {this, ret};
+  }
+
+  void process() {
+    if (!io_service_) return;
+
+    auto now = std::chrono::steady_clock::now();
+    while (!dq_.empty()) {
+      auto& x = dq_.front();
+      if (now - x.first < std::chrono::seconds(tick)) break;
+      if (x.second) {
+        CROW_LOG_DEBUG << "timer call: " << this << ' ' << step_;
+        // we know that timer handlers are very simple currenty; call here
+        x.second();
+      }
+      dq_.pop_front();
+      step_++;
+    }
+  }
+
+  void set_io_service(boost::asio::io_service& io_service) {
+    io_service_ = &io_service;
+  }
+
+  dumb_timer_queue() noexcept {}
+
+ private:
+  int tick{5};
+  boost::asio::io_service* io_service_{};
+  std::deque<std::pair<decltype(std::chrono::steady_clock::now()),
+                       std::function<void()>>>
+      dq_;
+  int step_{};
+};
+}
+}
diff --git a/crow/include/crow/http_connection.h b/crow/include/crow/http_connection.h
new file mode 100644
index 0000000..ed669c3
--- /dev/null
+++ b/crow/include/crow/http_connection.h
@@ -0,0 +1,548 @@
+#pragma once
+#include <atomic>
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/array.hpp>
+#include <boost/asio.hpp>
+#include <boost/lexical_cast.hpp>
+#include <chrono>
+#include <vector>
+
+#include "crow/http_parser_merged.h"
+
+#include "crow/dumb_timer_queue.h"
+#include "crow/http_response.h"
+#include "crow/logging.h"
+#include "crow/middleware_context.h"
+#include "crow/parser.h"
+#include "crow/settings.h"
+#include "crow/socket_adaptors.h"
+
+namespace crow {
+using namespace boost;
+using tcp = asio::ip::tcp;
+
+namespace detail {
+template <typename MW>
+struct check_before_handle_arity_3_const {
+  template <typename T, void (T::*)(request&, response&, typename MW::context&)
+                            const = &T::before_handle>
+  struct get {};
+};
+
+template <typename MW>
+struct check_before_handle_arity_3 {
+  template <typename T, void (T::*)(request&, response&,
+                                    typename MW::context&) = &T::before_handle>
+  struct get {};
+};
+
+template <typename MW>
+struct check_after_handle_arity_3_const {
+  template <typename T, void (T::*)(request&, response&, typename MW::context&)
+                            const = &T::after_handle>
+  struct get {};
+};
+
+template <typename MW>
+struct check_after_handle_arity_3 {
+  template <typename T, void (T::*)(request&, response&,
+                                    typename MW::context&) = &T::after_handle>
+  struct get {};
+};
+
+template <typename T>
+struct is_before_handle_arity_3_impl {
+  template <typename C>
+  static std::true_type f(
+      typename check_before_handle_arity_3_const<T>::template get<C>*);
+
+  template <typename C>
+  static std::true_type f(
+      typename check_before_handle_arity_3<T>::template get<C>*);
+
+  template <typename C>
+  static std::false_type f(...);
+
+ public:
+  static const bool value = decltype(f<T>(nullptr))::value;
+};
+
+template <typename T>
+struct is_after_handle_arity_3_impl {
+  template <typename C>
+  static std::true_type f(
+      typename check_after_handle_arity_3_const<T>::template get<C>*);
+
+  template <typename C>
+  static std::true_type f(
+      typename check_after_handle_arity_3<T>::template get<C>*);
+
+  template <typename C>
+  static std::false_type f(...);
+
+ public:
+  static const bool value = decltype(f<T>(nullptr))::value;
+};
+
+template <typename MW, typename Context, typename ParentContext>
+typename std::enable_if<!is_before_handle_arity_3_impl<MW>::value>::type
+before_handler_call(MW& mw, request& req, response& res, Context& ctx,
+                    ParentContext& /*parent_ctx*/) {
+  mw.before_handle(req, res, ctx.template get<MW>(), ctx);
+}
+
+template <typename MW, typename Context, typename ParentContext>
+typename std::enable_if<is_before_handle_arity_3_impl<MW>::value>::type
+before_handler_call(MW& mw, request& req, response& res, Context& ctx,
+                    ParentContext& /*parent_ctx*/) {
+  mw.before_handle(req, res, ctx.template get<MW>());
+}
+
+template <typename MW, typename Context, typename ParentContext>
+typename std::enable_if<!is_after_handle_arity_3_impl<MW>::value>::type
+after_handler_call(MW& mw, request& req, response& res, Context& ctx,
+                   ParentContext& /*parent_ctx*/) {
+  mw.after_handle(req, res, ctx.template get<MW>(), ctx);
+}
+
+template <typename MW, typename Context, typename ParentContext>
+typename std::enable_if<is_after_handle_arity_3_impl<MW>::value>::type
+after_handler_call(MW& mw, request& req, response& res, Context& ctx,
+                   ParentContext& /*parent_ctx*/) {
+  mw.after_handle(req, res, ctx.template get<MW>());
+}
+
+template <int N, typename Context, typename Container, typename CurrentMW,
+          typename... Middlewares>
+bool middleware_call_helper(Container& middlewares, request& req, response& res,
+                            Context& ctx) {
+  using parent_context_t = typename Context::template partial<N - 1>;
+  before_handler_call<CurrentMW, Context, parent_context_t>(
+      std::get<N>(middlewares), req, res, ctx,
+      static_cast<parent_context_t&>(ctx));
+
+  if (res.is_completed()) {
+    after_handler_call<CurrentMW, Context, parent_context_t>(
+        std::get<N>(middlewares), req, res, ctx,
+        static_cast<parent_context_t&>(ctx));
+    return true;
+  }
+
+  if (middleware_call_helper<N + 1, Context, Container, Middlewares...>(
+          middlewares, req, res, ctx)) {
+    after_handler_call<CurrentMW, Context, parent_context_t>(
+        std::get<N>(middlewares), req, res, ctx,
+        static_cast<parent_context_t&>(ctx));
+    return true;
+  }
+
+  return false;
+}
+
+template <int N, typename Context, typename Container>
+bool middleware_call_helper(Container& /*middlewares*/, request& /*req*/,
+                            response& /*res*/, Context& /*ctx*/) {
+  return false;
+}
+
+template <int N, typename Context, typename Container>
+typename std::enable_if<(N < 0)>::type after_handlers_call_helper(
+    Container& /*middlewares*/, Context& /*context*/, request& /*req*/,
+    response& /*res*/) {}
+
+template <int N, typename Context, typename Container>
+typename std::enable_if<(N == 0)>::type after_handlers_call_helper(
+    Container& middlewares, Context& ctx, request& req, response& res) {
+  using parent_context_t = typename Context::template partial<N - 1>;
+  using CurrentMW = typename std::tuple_element<
+      N, typename std::remove_reference<Container>::type>::type;
+  after_handler_call<CurrentMW, Context, parent_context_t>(
+      std::get<N>(middlewares), req, res, ctx,
+      static_cast<parent_context_t&>(ctx));
+}
+
+template <int N, typename Context, typename Container>
+typename std::enable_if<(N > 0)>::type after_handlers_call_helper(
+    Container& middlewares, Context& ctx, request& req, response& res) {
+  using parent_context_t = typename Context::template partial<N - 1>;
+  using CurrentMW = typename std::tuple_element<
+      N, typename std::remove_reference<Container>::type>::type;
+  after_handler_call<CurrentMW, Context, parent_context_t>(
+      std::get<N>(middlewares), req, res, ctx,
+      static_cast<parent_context_t&>(ctx));
+  after_handlers_call_helper<N - 1, Context, Container>(middlewares, ctx, req,
+                                                        res);
+}
+}
+
+#ifdef CROW_ENABLE_DEBUG
+static int connectionCount;
+#endif
+template <typename Adaptor, typename Handler, typename... Middlewares>
+class Connection {
+ public:
+  Connection(boost::asio::io_service& io_service, Handler* handler,
+             const std::string& server_name,
+             std::tuple<Middlewares...>* middlewares,
+             std::function<std::string()>& get_cached_date_str_f,
+             detail::dumb_timer_queue& timer_queue,
+             typename Adaptor::context* adaptor_ctx_)
+      : adaptor_(io_service, adaptor_ctx_),
+        handler_(handler),
+        parser_(this),
+        server_name_(server_name),
+        middlewares_(middlewares),
+        get_cached_date_str(get_cached_date_str_f),
+        timer_queue(timer_queue) {
+#ifdef CROW_ENABLE_DEBUG
+    connectionCount++;
+    CROW_LOG_DEBUG << "Connection open, total " << connectionCount << ", "
+                   << this;
+#endif
+  }
+
+  ~Connection() {
+    res.complete_request_handler_ = nullptr;
+    cancel_deadline_timer();
+#ifdef CROW_ENABLE_DEBUG
+    connectionCount--;
+    CROW_LOG_DEBUG << "Connection closed, total " << connectionCount << ", "
+                   << this;
+#endif
+  }
+
+  decltype(std::declval<Adaptor>().raw_socket())& socket() {
+    return adaptor_.raw_socket();
+  }
+
+  void start() {
+    adaptor_.start([this](const boost::system::error_code& ec) {
+      if (!ec) {
+        start_deadline();
+
+        do_read();
+      } else {
+        check_destroy();
+      }
+    });
+  }
+
+  void handle_header() {
+    // HTTP 1.1 Expect: 100-continue
+    if (parser_.check_version(1, 1) && parser_.headers.count("expect") &&
+        get_header_value(parser_.headers, "expect") == "100-continue") {
+      buffers_.clear();
+      static std::string expect_100_continue = "HTTP/1.1 100 Continue\r\n\r\n";
+      buffers_.emplace_back(expect_100_continue.data(),
+                            expect_100_continue.size());
+      do_write();
+    }
+  }
+
+  void handle() {
+    cancel_deadline_timer();
+    bool is_invalid_request = false;
+    add_keep_alive_ = false;
+
+    req_ = std::move(parser_.to_request());
+    request& req = req_;
+
+    if (parser_.check_version(1, 0)) {
+      // HTTP/1.0
+      if (req.headers.count("connection")) {
+        if (boost::iequals(req.get_header_value("connection"), "Keep-Alive"))
+          add_keep_alive_ = true;
+      } else
+        close_connection_ = true;
+    } else if (parser_.check_version(1, 1)) {
+      // HTTP/1.1
+      if (req.headers.count("connection")) {
+        if (req.get_header_value("connection") == "close")
+          close_connection_ = true;
+        else if (boost::iequals(req.get_header_value("connection"),
+                                "Keep-Alive"))
+          add_keep_alive_ = true;
+      }
+      if (!req.headers.count("host")) {
+        is_invalid_request = true;
+        res = response(400);
+      }
+      if (parser_.is_upgrade()) {
+        if (req.get_header_value("upgrade") == "h2c") {
+          // TODO HTTP/2
+          // currently, ignore upgrade header
+        } else {
+          close_connection_ = true;
+          handler_->handle_upgrade(req, res, std::move(adaptor_));
+          return;
+        }
+      }
+    }
+
+    CROW_LOG_INFO << "Request: " << boost::lexical_cast<std::string>(
+                                        adaptor_.remote_endpoint())
+                  << " " << this << " HTTP/" << parser_.http_major << "."
+                  << parser_.http_minor << ' ' << method_name(req.method) << " "
+                  << req.url;
+
+    need_to_call_after_handlers_ = false;
+    if (!is_invalid_request) {
+      res.complete_request_handler_ = [] {};
+      res.is_alive_helper_ = [this]() -> bool { return adaptor_.is_open(); };
+
+      ctx_ = detail::context<Middlewares...>();
+      req.middleware_context = (void*)&ctx_;
+      req.io_service = &adaptor_.get_io_service();
+      detail::middleware_call_helper<0, decltype(ctx_), decltype(*middlewares_),
+                                     Middlewares...>(*middlewares_, req, res,
+                                                     ctx_);
+
+      if (!res.completed_) {
+        res.complete_request_handler_ = [this] { this->complete_request(); };
+        need_to_call_after_handlers_ = true;
+        handler_->handle(req, res);
+        if (add_keep_alive_) res.set_header("connection", "Keep-Alive");
+      } else {
+        complete_request();
+      }
+    } else {
+      complete_request();
+    }
+  }
+
+  void complete_request() {
+    CROW_LOG_INFO << "Response: " << this << ' ' << req_.raw_url << ' '
+                  << res.code << ' ' << close_connection_;
+
+    if (need_to_call_after_handlers_) {
+      need_to_call_after_handlers_ = false;
+
+      // call all after_handler of middlewares
+      detail::after_handlers_call_helper<((int)sizeof...(Middlewares)-1),
+                                         decltype(ctx_),
+                                         decltype(*middlewares_)>(
+          *middlewares_, ctx_, req_, res);
+    }
+
+    // auto self = this->shared_from_this();
+    res.complete_request_handler_ = nullptr;
+
+    if (!adaptor_.is_open()) {
+      // CROW_LOG_DEBUG << this << " delete (socket is closed) " << is_reading
+      // << ' ' << is_writing;
+      // delete this;
+      return;
+    }
+
+    static std::unordered_map<int, std::string> statusCodes = {
+        {200, "HTTP/1.1 200 OK\r\n"},
+        {201, "HTTP/1.1 201 Created\r\n"},
+        {202, "HTTP/1.1 202 Accepted\r\n"},
+        {204, "HTTP/1.1 204 No Content\r\n"},
+
+        {300, "HTTP/1.1 300 Multiple Choices\r\n"},
+        {301, "HTTP/1.1 301 Moved Permanently\r\n"},
+        {302, "HTTP/1.1 302 Moved Temporarily\r\n"},
+        {304, "HTTP/1.1 304 Not Modified\r\n"},
+
+        {400, "HTTP/1.1 400 Bad Request\r\n"},
+        {401, "HTTP/1.1 401 Unauthorized\r\n"},
+        {403, "HTTP/1.1 403 Forbidden\r\n"},
+        {404, "HTTP/1.1 404 Not Found\r\n"},
+
+        {500, "HTTP/1.1 500 Internal Server Error\r\n"},
+        {501, "HTTP/1.1 501 Not Implemented\r\n"},
+        {502, "HTTP/1.1 502 Bad Gateway\r\n"},
+        {503, "HTTP/1.1 503 Service Unavailable\r\n"},
+    };
+
+    static std::string seperator = ": ";
+    static std::string crlf = "\r\n";
+
+    buffers_.clear();
+    buffers_.reserve(4 * (res.headers.size() + 5) + 3);
+
+    if (res.body.empty() && res.json_value.t() == json::type::Object) {
+      res.body = json::dump(res.json_value);
+    }
+
+    if (!statusCodes.count(res.code)) res.code = 500;
+    {
+      auto& status = statusCodes.find(res.code)->second;
+      buffers_.emplace_back(status.data(), status.size());
+    }
+
+    if (res.code >= 400 && res.body.empty())
+      res.body = statusCodes[res.code].substr(9);
+
+    for (auto& kv : res.headers) {
+      buffers_.emplace_back(kv.first.data(), kv.first.size());
+      buffers_.emplace_back(seperator.data(), seperator.size());
+      buffers_.emplace_back(kv.second.data(), kv.second.size());
+      buffers_.emplace_back(crlf.data(), crlf.size());
+    }
+
+    if (!res.headers.count("content-length")) {
+      content_length_ = std::to_string(res.body.size());
+      static std::string content_length_tag = "Content-Length: ";
+      buffers_.emplace_back(content_length_tag.data(),
+                            content_length_tag.size());
+      buffers_.emplace_back(content_length_.data(), content_length_.size());
+      buffers_.emplace_back(crlf.data(), crlf.size());
+    }
+    if (!res.headers.count("server")) {
+      static std::string server_tag = "Server: ";
+      buffers_.emplace_back(server_tag.data(), server_tag.size());
+      buffers_.emplace_back(server_name_.data(), server_name_.size());
+      buffers_.emplace_back(crlf.data(), crlf.size());
+    }
+    if (!res.headers.count("date")) {
+      static std::string date_tag = "Date: ";
+      date_str_ = get_cached_date_str();
+      buffers_.emplace_back(date_tag.data(), date_tag.size());
+      buffers_.emplace_back(date_str_.data(), date_str_.size());
+      buffers_.emplace_back(crlf.data(), crlf.size());
+    }
+    if (add_keep_alive_) {
+      static std::string keep_alive_tag = "Connection: Keep-Alive";
+      buffers_.emplace_back(keep_alive_tag.data(), keep_alive_tag.size());
+      buffers_.emplace_back(crlf.data(), crlf.size());
+    }
+
+    buffers_.emplace_back(crlf.data(), crlf.size());
+    res_body_copy_.swap(res.body);
+    buffers_.emplace_back(res_body_copy_.data(), res_body_copy_.size());
+
+    do_write();
+
+    if (need_to_start_read_after_complete_) {
+      need_to_start_read_after_complete_ = false;
+      start_deadline();
+      do_read();
+    }
+  }
+
+ private:
+  void do_read() {
+    // auto self = this->shared_from_this();
+    is_reading = true;
+    adaptor_.socket().async_read_some(
+        boost::asio::buffer(buffer_),
+        [this](const boost::system::error_code& ec,
+               std::size_t bytes_transferred) {
+          bool error_while_reading = true;
+          if (!ec) {
+            bool ret = parser_.feed(buffer_.data(), bytes_transferred);
+            if (ret && adaptor_.is_open()) {
+              error_while_reading = false;
+            }
+          }
+
+          if (error_while_reading) {
+            cancel_deadline_timer();
+            parser_.done();
+            adaptor_.close();
+            is_reading = false;
+            CROW_LOG_DEBUG << this << " from read(1)";
+            check_destroy();
+          } else if (close_connection_) {
+            cancel_deadline_timer();
+            parser_.done();
+            is_reading = false;
+            check_destroy();
+            // adaptor will close after write
+          } else if (!need_to_call_after_handlers_) {
+            start_deadline();
+            do_read();
+          } else {
+            // res will be completed later by user
+            need_to_start_read_after_complete_ = true;
+          }
+        });
+  }
+
+  void do_write() {
+    // auto self = this->shared_from_this();
+    is_writing = true;
+    boost::asio::async_write(adaptor_.socket(), buffers_,
+                             [&](const boost::system::error_code& ec,
+                                 std::size_t /*bytes_transferred*/) {
+                               is_writing = false;
+                               res.clear();
+                               res_body_copy_.clear();
+                               if (!ec) {
+                                 if (close_connection_) {
+                                   adaptor_.close();
+                                   CROW_LOG_DEBUG << this << " from write(1)";
+                                   check_destroy();
+                                 }
+                               } else {
+                                 CROW_LOG_DEBUG << this << " from write(2)";
+                                 check_destroy();
+                               }
+                             });
+  }
+
+  void check_destroy() {
+    CROW_LOG_DEBUG << this << " is_reading " << is_reading << " is_writing "
+                   << is_writing;
+    if (!is_reading && !is_writing) {
+      CROW_LOG_DEBUG << this << " delete (idle) ";
+      delete this;
+    }
+  }
+
+  void cancel_deadline_timer() {
+    CROW_LOG_DEBUG << this << " timer cancelled: " << timer_cancel_key_.first
+                   << ' ' << timer_cancel_key_.second;
+    timer_queue.cancel(timer_cancel_key_);
+  }
+
+  void start_deadline(/*int timeout = 5*/) {
+    cancel_deadline_timer();
+
+    timer_cancel_key_ = timer_queue.add([this] {
+      if (!adaptor_.is_open()) {
+        return;
+      }
+      adaptor_.close();
+    });
+    CROW_LOG_DEBUG << this << " timer added: " << timer_cancel_key_.first << ' '
+                   << timer_cancel_key_.second;
+  }
+
+ private:
+  Adaptor adaptor_;
+  Handler* handler_;
+
+  boost::array<char, 4096> buffer_;
+
+  HTTPParser<Connection> parser_;
+  request req_;
+  response res;
+
+  bool close_connection_ = false;
+
+  const std::string& server_name_;
+  std::vector<boost::asio::const_buffer> buffers_;
+
+  std::string content_length_;
+  std::string date_str_;
+  std::string res_body_copy_;
+
+  // boost::asio::deadline_timer deadline_;
+  detail::dumb_timer_queue::key timer_cancel_key_;
+
+  bool is_reading{};
+  bool is_writing{};
+  bool need_to_call_after_handlers_{};
+  bool need_to_start_read_after_complete_{};
+  bool add_keep_alive_{};
+
+  std::tuple<Middlewares...>* middlewares_;
+  detail::context<Middlewares...> ctx_;
+
+  std::function<std::string()>& get_cached_date_str;
+  detail::dumb_timer_queue& timer_queue;
+};
+}
diff --git a/crow/include/crow/http_parser_merged.h b/crow/include/crow/http_parser_merged.h
new file mode 100644
index 0000000..120f9ac
--- /dev/null
+++ b/crow/include/crow/http_parser_merged.h
@@ -0,0 +1,2638 @@
+/* merged revision: 5b951d74bd66ec9d38448e0a85b1cf8b85d97db3 */
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#ifndef CROW_http_parser_h
+#define CROW_http_parser_h
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Also update SONAME in the Makefile whenever you change these. */
+#define CROW_HTTP_PARSER_VERSION_MAJOR 2
+#define CROW_HTTP_PARSER_VERSION_MINOR 3
+#define CROW_HTTP_PARSER_VERSION_PATCH 0
+
+#include <sys/types.h>
+#if defined(_WIN32) && !defined(__MINGW32__) && \
+    (!defined(_MSC_VER) || _MSC_VER < 1600)
+#include <BaseTsd.h>
+#include <stddef.h>
+typedef __int8 int8_t;
+typedef unsigned __int8 uint8_t;
+typedef __int16 int16_t;
+typedef unsigned __int16 uint16_t;
+typedef __int32 int32_t;
+typedef unsigned __int32 uint32_t;
+typedef __int64 int64_t;
+typedef unsigned __int64 uint64_t;
+#else
+#include <stdint.h>
+#endif
+
+/* Compile with -DHTTP_PARSER_STRICT=0 to make less checks, but run
+ * faster
+ */
+#ifndef CROW_HTTP_PARSER_STRICT
+#define CROW_HTTP_PARSER_STRICT 1
+#endif
+
+/* Maximium header size allowed. If the macro is not defined
+ * before including this header then the default is used. To
+ * change the maximum header size, define the macro in the build
+ * environment (e.g. -DHTTP_MAX_HEADER_SIZE=<value>). To remove
+ * the effective limit on the size of the header, define the macro
+ * to a very large number (e.g. -DHTTP_MAX_HEADER_SIZE=0x7fffffff)
+ */
+#ifndef CROW_HTTP_MAX_HEADER_SIZE
+#define CROW_HTTP_MAX_HEADER_SIZE (80 * 1024)
+#endif
+
+typedef struct http_parser http_parser;
+typedef struct http_parser_settings http_parser_settings;
+
+/* Callbacks should return non-zero to indicate an error. The parser will
+ * then halt execution.
+ *
+ * The one exception is on_headers_complete. In a HTTP_RESPONSE parser
+ * returning '1' from on_headers_complete will tell the parser that it
+ * should not expect a body. This is used when receiving a response to a
+ * HEAD request which may contain 'Content-Length' or 'Transfer-Encoding:
+ * chunked' headers that indicate the presence of a body.
+ *
+ * http_data_cb does not return data chunks. It will be call arbitrarally
+ * many times for each string. E.G. you might get 10 callbacks for "on_url"
+ * each providing just a few characters more data.
+ */
+typedef int (*http_data_cb)(http_parser *, const char *at, size_t length);
+typedef int (*http_cb)(http_parser *);
+
+/* Request Methods */
+#define CROW_HTTP_METHOD_MAP(CROW_XX)   \
+  CROW_XX(0, DELETE, DELETE)            \
+  CROW_XX(1, GET, GET)                  \
+  CROW_XX(2, HEAD, HEAD)                \
+  CROW_XX(3, POST, POST)                \
+  CROW_XX(4, PUT, PUT)                  \
+  /* pathological */                    \
+  CROW_XX(5, CONNECT, CONNECT)          \
+  CROW_XX(6, OPTIONS, OPTIONS)          \
+  CROW_XX(7, TRACE, TRACE)              \
+  /* webdav */                          \
+  CROW_XX(8, COPY, COPY)                \
+  CROW_XX(9, LOCK, LOCK)                \
+  CROW_XX(10, MKCOL, MKCOL)             \
+  CROW_XX(11, MOVE, MOVE)               \
+  CROW_XX(12, PROPFIND, PROPFIND)       \
+  CROW_XX(13, PROPPATCH, PROPPATCH)     \
+  CROW_XX(14, SEARCH, SEARCH)           \
+  CROW_XX(15, UNLOCK, UNLOCK)           \
+  /* subversion */                      \
+  CROW_XX(16, REPORT, REPORT)           \
+  CROW_XX(17, MKACTIVITY, MKACTIVITY)   \
+  CROW_XX(18, CHECKOUT, CHECKOUT)       \
+  CROW_XX(19, MERGE, MERGE)             \
+  /* upnp */                            \
+  CROW_XX(20, MSEARCH, M - SEARCH)      \
+  CROW_XX(21, NOTIFY, NOTIFY)           \
+  CROW_XX(22, SUBSCRIBE, SUBSCRIBE)     \
+  CROW_XX(23, UNSUBSCRIBE, UNSUBSCRIBE) \
+  /* RFC-5789 */                        \
+  CROW_XX(24, PATCH, PATCH)             \
+  CROW_XX(25, PURGE, PURGE)             \
+  /* CalDAV */                          \
+  CROW_XX(26, MKCALENDAR, MKCALENDAR)
+
+enum http_method {
+#define CROW_XX(num, name, string) HTTP_##name = num,
+  CROW_HTTP_METHOD_MAP(CROW_XX)
+#undef CROW_XX
+};
+
+enum http_parser_type { HTTP_REQUEST, HTTP_RESPONSE, HTTP_BOTH };
+
+/* Flag values for http_parser.flags field */
+enum flags {
+  F_CHUNKED = 1 << 0,
+  F_CONNECTION_KEEP_ALIVE = 1 << 1,
+  F_CONNECTION_CLOSE = 1 << 2,
+  F_TRAILING = 1 << 3,
+  F_UPGRADE = 1 << 4,
+  F_SKIPBODY = 1 << 5
+};
+
+/* Map for errno-related constants
+ *
+ * The provided argument should be a macro that takes 2 arguments.
+ */
+#define CROW_HTTP_ERRNO_MAP(CROW_XX)                                        \
+  /* No error */                                                            \
+  CROW_XX(OK, "success")                                                    \
+                                                                            \
+  /* Callback-related errors */                                             \
+  CROW_XX(CB_message_begin, "the on_message_begin callback failed")         \
+  CROW_XX(CB_url, "the on_url callback failed")                             \
+  CROW_XX(CB_header_field, "the on_header_field callback failed")           \
+  CROW_XX(CB_header_value, "the on_header_value callback failed")           \
+  CROW_XX(CB_headers_complete, "the on_headers_complete callback failed")   \
+  CROW_XX(CB_body, "the on_body callback failed")                           \
+  CROW_XX(CB_message_complete, "the on_message_complete callback failed")   \
+  CROW_XX(CB_status, "the on_status callback failed")                       \
+                                                                            \
+  /* Parsing-related errors */                                              \
+  CROW_XX(INVALID_EOF_STATE, "stream ended at an unexpected time")          \
+  CROW_XX(HEADER_OVERFLOW, "too many header bytes seen; overflow detected") \
+  CROW_XX(CLOSED_CONNECTION,                                                \
+          "data received after completed connection: close message")        \
+  CROW_XX(INVALID_VERSION, "invalid HTTP version")                          \
+  CROW_XX(INVALID_STATUS, "invalid HTTP status code")                       \
+  CROW_XX(INVALID_METHOD, "invalid HTTP method")                            \
+  CROW_XX(INVALID_URL, "invalid URL")                                       \
+  CROW_XX(INVALID_HOST, "invalid host")                                     \
+  CROW_XX(INVALID_PORT, "invalid port")                                     \
+  CROW_XX(INVALID_PATH, "invalid path")                                     \
+  CROW_XX(INVALID_QUERY_STRING, "invalid query string")                     \
+  CROW_XX(INVALID_FRAGMENT, "invalid fragment")                             \
+  CROW_XX(LF_EXPECTED, "CROW_LF character expected")                        \
+  CROW_XX(INVALID_HEADER_TOKEN, "invalid character in header")              \
+  CROW_XX(INVALID_CONTENT_LENGTH,                                           \
+          "invalid character in content-length header")                     \
+  CROW_XX(INVALID_CHUNK_SIZE, "invalid character in chunk size header")     \
+  CROW_XX(INVALID_CONSTANT, "invalid constant string")                      \
+  CROW_XX(INVALID_INTERNAL_STATE, "encountered unexpected internal state")  \
+  CROW_XX(STRICT, "strict mode assertion failed")                           \
+  CROW_XX(PAUSED, "parser is paused")                                       \
+  CROW_XX(UNKNOWN, "an unknown error occurred")
+
+/* Define HPE_* values for each errno value above */
+#define CROW_HTTP_ERRNO_GEN(n, s) HPE_##n,
+enum http_errno { CROW_HTTP_ERRNO_MAP(CROW_HTTP_ERRNO_GEN) };
+#undef CROW_HTTP_ERRNO_GEN
+
+/* Get an http_errno value from an http_parser */
+#define CROW_HTTP_PARSER_ERRNO(p) ((enum http_errno)(p)->http_errno)
+
+struct http_parser {
+  /** PRIVATE **/
+  unsigned int type : 2;         /* enum http_parser_type */
+  unsigned int flags : 6;        /* F_* values from 'flags' enum; semi-public */
+  unsigned int state : 8;        /* enum state from http_parser.c */
+  unsigned int header_state : 8; /* enum header_state from http_parser.c */
+  unsigned int index : 8;        /* index into current matcher */
+
+  uint32_t nread;          /* # bytes read in various scenarios */
+  uint64_t content_length; /* # bytes in body (0 if no Content-Length header) */
+
+  /** READ-ONLY **/
+  unsigned short http_major;
+  unsigned short http_minor;
+  unsigned int status_code : 16; /* responses only */
+  unsigned int method : 8;       /* requests only */
+  unsigned int http_errno : 7;
+
+  /* 1 = Upgrade header was present and the parser has exited because of that.
+   * 0 = No upgrade header present.
+   * Should be checked when http_parser_execute() returns in addition to
+   * error checking.
+   */
+  unsigned int upgrade : 1;
+
+  /** PUBLIC **/
+  void *data; /* A pointer to get hook to the "connection" or "socket" object */
+};
+
+struct http_parser_settings {
+  http_cb on_message_begin;
+  http_data_cb on_url;
+  http_data_cb on_status;
+  http_data_cb on_header_field;
+  http_data_cb on_header_value;
+  http_cb on_headers_complete;
+  http_data_cb on_body;
+  http_cb on_message_complete;
+};
+
+enum http_parser_url_fields {
+  UF_SCHEMA = 0,
+  UF_HOST = 1,
+  UF_PORT = 2,
+  UF_PATH = 3,
+  UF_QUERY = 4,
+  UF_FRAGMENT = 5,
+  UF_USERINFO = 6,
+  UF_MAX = 7
+};
+
+/* Result structure for http_parser_parse_url().
+ *
+ * Callers should index into field_data[] with UF_* values iff field_set
+ * has the relevant (1 << UF_*) bit set. As a courtesy to clients (and
+ * because we probably have padding left over), we convert any port to
+ * a uint16_t.
+ */
+struct http_parser_url {
+  uint16_t field_set; /* Bitmask of (1 << UF_*) values */
+  uint16_t port;      /* Converted UF_PORT string */
+
+  struct {
+    uint16_t off; /* Offset into buffer in which field starts */
+    uint16_t len; /* Length of run in buffer */
+  } field_data[UF_MAX];
+};
+
+/* Returns the library version. Bits 16-23 contain the major version number,
+ * bits 8-15 the minor version number and bits 0-7 the patch level.
+ * Usage example:
+ *
+ *   unsigned long version = http_parser_version();
+ *   unsigned major = (version >> 16) & 255;
+ *   unsigned minor = (version >> 8) & 255;
+ *   unsigned patch = version & 255;
+ *   printf("http_parser v%u.%u.%u\n", major, minor, version);
+ */
+unsigned long http_parser_version(void);
+
+void http_parser_init(http_parser *parser, enum http_parser_type type);
+
+size_t http_parser_execute(http_parser *parser,
+                           const http_parser_settings *settings,
+                           const char *data, size_t len);
+
+/* If http_should_keep_alive() in the on_headers_complete or
+ * on_message_complete callback returns 0, then this should be
+ * the last message on the connection.
+ * If you are the server, respond with the "Connection: close" header.
+ * If you are the client, close the connection.
+ */
+int http_should_keep_alive(const http_parser *parser);
+
+/* Returns a string version of the HTTP method. */
+const char *http_method_str(enum http_method m);
+
+/* Return a string name of the given error */
+const char *http_errno_name(enum http_errno err);
+
+/* Return a string description of the given error */
+const char *http_errno_description(enum http_errno err);
+
+/* Parse a URL; return nonzero on failure */
+int http_parser_parse_url(const char *buf, size_t buflen, int is_connect,
+                          struct http_parser_url *u);
+
+/* Pause or un-pause the parser; a nonzero value pauses */
+void http_parser_pause(http_parser *parser, int paused);
+
+/* Checks if this is the final chunk of the body. */
+int http_body_is_final(const http_parser *parser);
+
+/*#include "http_parser.h"*/
+/* Based on src/http/ngx_http_parse.c from NGINX copyright Igor Sysoev
+ *
+ * Additional changes are licensed under the same terms as NGINX and
+ * copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+#include <assert.h>
+#include <ctype.h>
+#include <limits.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifndef CROW_ULLONG_MAX
+#define CROW_ULLONG_MAX ((uint64_t)-1) /* 2^64-1 */
+#endif
+
+#ifndef CROW_MIN
+#define CROW_MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+#ifndef CROW_ARRAY_SIZE
+#define CROW_ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
+#endif
+
+#ifndef CROW_BIT_AT
+#define CROW_BIT_AT(a, i) \
+  (!!((unsigned int)(a)[(unsigned int)(i) >> 3] & (1 << ((unsigned int)(i)&7))))
+#endif
+
+#ifndef CROW_ELEM_AT
+#define CROW_ELEM_AT(a, i, v) \
+  ((unsigned int)(i) < CROW_ARRAY_SIZE(a) ? (a)[(i)] : (v))
+#endif
+
+#define CROW_SET_ERRNO(e)     \
+  do {                        \
+    parser->http_errno = (e); \
+  } while (0)
+
+/* Run the notify callback FOR, returning ER if it fails */
+#define CROW_CALLBACK_NOTIFY_(FOR, ER)                     \
+  do {                                                     \
+    assert(CROW_HTTP_PARSER_ERRNO(parser) == HPE_OK);      \
+                                                           \
+    if (settings->on_##FOR) {                              \
+      if (0 != settings->on_##FOR(parser)) {               \
+        CROW_SET_ERRNO(HPE_CB_##FOR);                      \
+      }                                                    \
+                                                           \
+      /* We either errored above or got paused; get out */ \
+      if (CROW_HTTP_PARSER_ERRNO(parser) != HPE_OK) {      \
+        return (ER);                                       \
+      }                                                    \
+    }                                                      \
+  } while (0)
+
+/* Run the notify callback FOR and consume the current byte */
+#define CROW_CALLBACK_NOTIFY(FOR) CROW_CALLBACK_NOTIFY_(FOR, p - data + 1)
+
+/* Run the notify callback FOR and don't consume the current byte */
+#define CROW_CALLBACK_NOTIFY_NOADVANCE(FOR) CROW_CALLBACK_NOTIFY_(FOR, p - data)
+
+/* Run data callback FOR with LEN bytes, returning ER if it fails */
+#define CROW_CALLBACK_DATA_(FOR, LEN, ER)                         \
+  do {                                                            \
+    assert(CROW_HTTP_PARSER_ERRNO(parser) == HPE_OK);             \
+                                                                  \
+    if (FOR##_mark) {                                             \
+      if (settings->on_##FOR) {                                   \
+        if (0 != settings->on_##FOR(parser, FOR##_mark, (LEN))) { \
+          CROW_SET_ERRNO(HPE_CB_##FOR);                           \
+        }                                                         \
+                                                                  \
+        /* We either errored above or got paused; get out */      \
+        if (CROW_HTTP_PARSER_ERRNO(parser) != HPE_OK) {           \
+          return (ER);                                            \
+        }                                                         \
+      }                                                           \
+      FOR##_mark = NULL;                                          \
+    }                                                             \
+  } while (0)
+
+/* Run the data callback FOR and consume the current byte */
+#define CROW_CALLBACK_DATA(FOR) \
+  CROW_CALLBACK_DATA_(FOR, p - FOR##_mark, p - data + 1)
+
+/* Run the data callback FOR and don't consume the current byte */
+#define CROW_CALLBACK_DATA_NOADVANCE(FOR) \
+  CROW_CALLBACK_DATA_(FOR, p - FOR##_mark, p - data)
+
+/* Set the mark FOR; non-destructive if mark is already set */
+#define CROW_MARK(FOR) \
+  do {                 \
+    if (!FOR##_mark) { \
+      FOR##_mark = p;  \
+    }                  \
+  } while (0)
+
+#define CROW_PROXY_CONNECTION "proxy-connection"
+#define CROW_CONNECTION "connection"
+#define CROW_CONTENT_LENGTH "content-length"
+#define CROW_TRANSFER_ENCODING "transfer-encoding"
+#define CROW_UPGRADE "upgrade"
+#define CROW_CHUNKED "chunked"
+#define CROW_KEEP_ALIVE "keep-alive"
+#define CROW_CLOSE "close"
+
+enum state {
+  s_dead = 1 /* important that this is > 0 */
+
+  ,
+  s_start_req_or_res,
+  s_res_or_resp_H,
+  s_start_res,
+  s_res_H,
+  s_res_HT,
+  s_res_HTT,
+  s_res_HTTP,
+  s_res_first_http_major,
+  s_res_http_major,
+  s_res_first_http_minor,
+  s_res_http_minor,
+  s_res_first_status_code,
+  s_res_status_code,
+  s_res_status_start,
+  s_res_status,
+  s_res_line_almost_done
+
+  ,
+  s_start_req
+
+  ,
+  s_req_method,
+  s_req_spaces_before_url,
+  s_req_schema,
+  s_req_schema_slash,
+  s_req_schema_slash_slash,
+  s_req_server_start,
+  s_req_server,
+  s_req_server_with_at,
+  s_req_path,
+  s_req_query_string_start,
+  s_req_query_string,
+  s_req_fragment_start,
+  s_req_fragment,
+  s_req_http_start,
+  s_req_http_H,
+  s_req_http_HT,
+  s_req_http_HTT,
+  s_req_http_HTTP,
+  s_req_first_http_major,
+  s_req_http_major,
+  s_req_first_http_minor,
+  s_req_http_minor,
+  s_req_line_almost_done
+
+  ,
+  s_header_field_start,
+  s_header_field,
+  s_header_value_discard_ws,
+  s_header_value_discard_ws_almost_done,
+  s_header_value_discard_lws,
+  s_header_value_start,
+  s_header_value,
+  s_header_value_lws
+
+  ,
+  s_header_almost_done
+
+  ,
+  s_chunk_size_start,
+  s_chunk_size,
+  s_chunk_parameters,
+  s_chunk_size_almost_done
+
+  ,
+  s_headers_almost_done,
+  s_headers_done
+
+  /* Important: 's_headers_done' must be the last 'header' state. All
+   * states beyond this must be 'body' states. It is used for overflow
+   * checking. See the CROW_PARSING_HEADER() macro.
+   */
+
+  ,
+  s_chunk_data,
+  s_chunk_data_almost_done,
+  s_chunk_data_done
+
+  ,
+  s_body_identity,
+  s_body_identity_eof
+
+  ,
+  s_message_done
+};
+
+#define CROW_PARSING_HEADER(state) (state <= s_headers_done)
+
+enum header_states {
+  h_general = 0,
+  h_C,
+  h_CO,
+  h_CON
+
+  ,
+  h_matching_connection,
+  h_matching_proxy_connection,
+  h_matching_content_length,
+  h_matching_transfer_encoding,
+  h_matching_upgrade
+
+  ,
+  h_connection,
+  h_content_length,
+  h_transfer_encoding,
+  h_upgrade
+
+  ,
+  h_matching_transfer_encoding_chunked,
+  h_matching_connection_keep_alive,
+  h_matching_connection_close
+
+  ,
+  h_transfer_encoding_chunked,
+  h_connection_keep_alive,
+  h_connection_close
+};
+
+enum http_host_state {
+  s_http_host_dead = 1,
+  s_http_userinfo_start,
+  s_http_userinfo,
+  s_http_host_start,
+  s_http_host_v6_start,
+  s_http_host,
+  s_http_host_v6,
+  s_http_host_v6_end,
+  s_http_host_port_start,
+  s_http_host_port
+};
+
+/* Macros for character classes; depends on strict-mode  */
+#define CROW_CR '\r'
+#define CROW_LF '\n'
+#define CROW_LOWER(c) (unsigned char)(c | 0x20)
+#define CROW_IS_ALPHA(c) (CROW_LOWER(c) >= 'a' && CROW_LOWER(c) <= 'z')
+#define CROW_IS_NUM(c) ((c) >= '0' && (c) <= '9')
+#define CROW_IS_ALPHANUM(c) (CROW_IS_ALPHA(c) || CROW_IS_NUM(c))
+#define CROW_IS_HEX(c) \
+  (CROW_IS_NUM(c) || (CROW_LOWER(c) >= 'a' && CROW_LOWER(c) <= 'f'))
+#define CROW_IS_MARK(c)                                                  \
+  ((c) == '-' || (c) == '_' || (c) == '.' || (c) == '!' || (c) == '~' || \
+   (c) == '*' || (c) == '\'' || (c) == '(' || (c) == ')')
+#define CROW_IS_USERINFO_CHAR(c)                                         \
+  (CROW_IS_ALPHANUM(c) || CROW_IS_MARK(c) || (c) == '%' || (c) == ';' || \
+   (c) == ':' || (c) == '&' || (c) == '=' || (c) == '+' || (c) == '$' || \
+   (c) == ',')
+
+#if CROW_HTTP_PARSER_STRICT
+#define CROW_TOKEN(c) (tokens[(unsigned char)c])
+#define CROW_IS_URL_CHAR(c) (CROW_BIT_AT(normal_url_char, (unsigned char)c))
+#define CROW_IS_HOST_CHAR(c) (CROW_IS_ALPHANUM(c) || (c) == '.' || (c) == '-')
+#else
+#define CROW_TOKEN(c) ((c == ' ') ? ' ' : tokens[(unsigned char)c])
+#define CROW_IS_URL_CHAR(c) \
+  (CROW_BIT_AT(normal_url_char, (unsigned char)c) || ((c)&0x80))
+#define CROW_IS_HOST_CHAR(c) \
+  (CROW_IS_ALPHANUM(c) || (c) == '.' || (c) == '-' || (c) == '_')
+#endif
+
+#define CROW_start_state \
+  (parser->type == HTTP_REQUEST ? s_start_req : s_start_res)
+
+#if CROW_HTTP_PARSER_STRICT
+#define CROW_STRICT_CHECK(cond)   \
+  do {                            \
+    if (cond) {                   \
+      CROW_SET_ERRNO(HPE_STRICT); \
+      goto error;                 \
+    }                             \
+  } while (0)
+#define CROW_NEW_MESSAGE() \
+  (http_should_keep_alive(parser) ? CROW_start_state : s_dead)
+#else
+#define CROW_STRICT_CHECK(cond)
+#define CROW_NEW_MESSAGE() CROW_start_state
+#endif
+
+int http_message_needs_eof(const http_parser *parser);
+
+/* Our URL parser.
+ *
+ * This is designed to be shared by http_parser_execute() for URL validation,
+ * hence it has a state transition + byte-for-byte interface. In addition, it
+ * is meant to be embedded in http_parser_parse_url(), which does the dirty
+ * work of turning state transitions URL components for its API.
+ *
+ * This function should only be invoked with non-space characters. It is
+ * assumed that the caller cares about (and can detect) the transition between
+ * URL and non-URL states by looking for these.
+ */
+inline enum state parse_url_char(enum state s, const char ch) {
+#if CROW_HTTP_PARSER_STRICT
+#define CROW_T(v) 0
+#else
+#define CROW_T(v) v
+#endif
+
+  static const uint8_t
+      normal_url_char
+          [32] =
+              {
+                  /*   0 nul    1 soh    2 stx    3 etx    4 eot    5 enq    6
+                     ack    7 bel  */
+                  0 | 0 | 0 | 0 | 0 | 0 | 0 | 0,
+                  /*   8 bs     9 ht    10 nl    11 vt    12 np    13 cr    14
+                     so    15 si   */
+                  0 | CROW_T(2) | 0 | 0 | CROW_T(16) | 0 | 0 | 0,
+                  /*  16 dle   17 dc1   18 dc2   19 dc3   20 dc4   21 nak   22
+                     syn   23 etb */
+                  0 | 0 | 0 | 0 | 0 | 0 | 0 | 0,
+                  /*  24 can   25 em    26 sub   27 esc   28 fs    29 gs    30
+                     rs    31 us  */
+                  0 | 0 | 0 | 0 | 0 | 0 | 0 | 0,
+                  /*  32 sp    33  !    34  "    35  #    36  $    37  %    38
+                     &    39  '  */
+                  0 | 2 | 4 | 0 | 16 | 32 | 64 | 128,
+                  /*  40  (    41  )    42  *    43  +    44  ,    45  -    46
+                     .    47  /  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  48  0    49  1    50  2    51  3    52  4    53  5    54
+                     6    55  7  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  56  8    57  9    58  :    59  ;    60  <    61  =    62
+                     >    63  ?  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 0,
+                  /*  64  @    65  A    66  B    67  C    68  D    69  E    70
+                     F    71  G  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  72  H    73  I    74  J    75  K    76  L    77  M    78
+                     N    79  O  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  80  P    81  Q    82  R    83  S    84  CROW_T    85  U
+                     86  V    87  W  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  88  X    89  Y    90  Z    91  [    92  \    93  ]    94
+                     ^    95  _  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /*  96  `    97  a    98  b    99  c   100  d   101  e   102
+                     f   103  g  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /* 104  h   105  i   106  j   107  k   108  l   109  m   110
+                     n   111  o  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /* 112  p   113  q   114  r   115  s   116  t   117  u   118
+                     v   119  w  */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 128,
+                  /* 120  x   121  y   122  z   123  {   124  |   125  }   126
+                     ~   127 del */
+                  1 | 2 | 4 | 8 | 16 | 32 | 64 | 0,
+              };
+
+#undef CROW_T
+
+  if (ch == ' ' || ch == '\r' || ch == '\n') {
+    return s_dead;
+  }
+
+#if CROW_HTTP_PARSER_STRICT
+  if (ch == '\t' || ch == '\f') {
+    return s_dead;
+  }
+#endif
+
+  switch (s) {
+    case s_req_spaces_before_url:
+      /* Proxied requests are followed by scheme of an absolute URI (alpha).
+       * All methods except CONNECT are followed by '/' or '*'.
+       */
+
+      if (ch == '/' || ch == '*') {
+        return s_req_path;
+      }
+
+      if (CROW_IS_ALPHA(ch)) {
+        return s_req_schema;
+      }
+
+      break;
+
+    case s_req_schema:
+      if (CROW_IS_ALPHA(ch)) {
+        return s;
+      }
+
+      if (ch == ':') {
+        return s_req_schema_slash;
+      }
+
+      break;
+
+    case s_req_schema_slash:
+      if (ch == '/') {
+        return s_req_schema_slash_slash;
+      }
+
+      break;
+
+    case s_req_schema_slash_slash:
+      if (ch == '/') {
+        return s_req_server_start;
+      }
+
+      break;
+
+    case s_req_server_with_at:
+      if (ch == '@') {
+        return s_dead;
+      }
+
+    /* FALLTHROUGH */
+    case s_req_server_start:
+    case s_req_server:
+      if (ch == '/') {
+        return s_req_path;
+      }
+
+      if (ch == '?') {
+        return s_req_query_string_start;
+      }
+
+      if (ch == '@') {
+        return s_req_server_with_at;
+      }
+
+      if (CROW_IS_USERINFO_CHAR(ch) || ch == '[' || ch == ']') {
+        return s_req_server;
+      }
+
+      break;
+
+    case s_req_path:
+      if (CROW_IS_URL_CHAR(ch)) {
+        return s;
+      }
+
+      switch (ch) {
+        case '?':
+          return s_req_query_string_start;
+
+        case '#':
+          return s_req_fragment_start;
+      }
+
+      break;
+
+    case s_req_query_string_start:
+    case s_req_query_string:
+      if (CROW_IS_URL_CHAR(ch)) {
+        return s_req_query_string;
+      }
+
+      switch (ch) {
+        case '?':
+          /* allow extra '?' in query string */
+          return s_req_query_string;
+
+        case '#':
+          return s_req_fragment_start;
+      }
+
+      break;
+
+    case s_req_fragment_start:
+      if (CROW_IS_URL_CHAR(ch)) {
+        return s_req_fragment;
+      }
+
+      switch (ch) {
+        case '?':
+          return s_req_fragment;
+
+        case '#':
+          return s;
+      }
+
+      break;
+
+    case s_req_fragment:
+      if (CROW_IS_URL_CHAR(ch)) {
+        return s;
+      }
+
+      switch (ch) {
+        case '?':
+        case '#':
+          return s;
+      }
+
+      break;
+
+    default:
+      break;
+  }
+
+  /* We should never fall out of the switch above unless there's an error */
+  return s_dead;
+}
+
+inline size_t http_parser_execute(http_parser *parser,
+                                  const http_parser_settings *settings,
+                                  const char *data, size_t len) {
+  static const char *method_strings[] = {
+#define CROW_XX(num, name, string) #string,
+      CROW_HTTP_METHOD_MAP(CROW_XX)
+#undef CROW_XX
+  };
+
+  /* Tokens as defined by rfc 2616. Also lowercases them.
+   *        token       = 1*<any CHAR except CTLs or separators>
+   *     separators     = "(" | ")" | "<" | ">" | "@"
+   *                    | "," | ";" | ":" | "\" | <">
+   *                    | "/" | "[" | "]" | "?" | "="
+   *                    | "{" | "}" | SP | HT
+   */
+  static const char
+      tokens[256] = {/*   0 nul    1 soh    2 stx    3 etx    4 eot    5 enq
+                        6 ack    7 bel  */
+                     0,
+                     0, 0, 0, 0, 0, 0, 0,
+                     /*   8 bs     9 ht    10 nl    11 vt    12 np    13 cr
+                        14 so    15 si   */
+                     0,
+                     0, 0, 0, 0, 0, 0, 0,
+                     /*  16 dle   17 dc1   18 dc2   19 dc3   20 dc4   21 nak
+                        22 syn   23 etb */
+                     0,
+                     0, 0, 0, 0, 0, 0, 0,
+                     /*  24 can   25 em    26 sub   27 esc   28 fs    29 gs
+                        30 rs    31 us  */
+                     0,
+                     0, 0, 0, 0, 0, 0, 0,
+                     /*  32 sp    33  !    34  "    35  #    36  $    37  %
+                        38  &    39  '  */
+                     0,
+                     '!', 0, '#', '$', '%', '&', '\'',
+                     /*  40  (    41  )    42  *    43  +    44  ,    45  -
+                        46  .    47  /  */
+                     0,
+                     0, '*', '+', 0, '-', '.', 0,
+                     /*  48  0    49  1    50  2    51  3    52  4    53  5
+                        54  6    55  7  */
+                     '0',
+                     '1', '2', '3', '4', '5', '6', '7',
+                     /*  56  8    57  9    58  :    59  ;    60  <    61  =
+                        62  >    63  ?  */
+                     '8',
+                     '9', 0, 0, 0, 0, 0, 0,
+                     /*  64  @    65  A    66  B    67  C    68  D    69  E
+                        70  F    71  G  */
+                     0,
+                     'a', 'b', 'c', 'd', 'e', 'f', 'g',
+                     /*  72  H    73  I    74  J    75  K    76  L    77  M
+                        78  N    79  O  */
+                     'h',
+                     'i', 'j', 'k', 'l', 'm', 'n', 'o',
+                     /*  80  P    81  Q    82  R    83  S    84  T    85  U
+                        86  V    87  W  */
+                     'p',
+                     'q', 'r', 's', 't', 'u', 'v', 'w',
+                     /*  88  X    89  Y    90  Z    91  [    92  \    93  ]
+                        94  ^    95  _  */
+                     'x',
+                     'y', 'z', 0, 0, 0, '^', '_',
+                     /*  96  `    97  a    98  b    99  c   100  d   101  e
+                        102  f   103  g  */
+                     '`',
+                     'a', 'b', 'c', 'd', 'e', 'f', 'g',
+                     /* 104  h   105  i   106  j   107  k   108  l   109  m
+                        110  n   111  o  */
+                     'h',
+                     'i', 'j', 'k', 'l', 'm', 'n', 'o',
+                     /* 112  p   113  q   114  r   115  s   116  t   117  u
+                        118  v   119  w  */
+                     'p',
+                     'q', 'r', 's', 't', 'u', 'v', 'w',
+                     /* 120  x   121  y   122  z   123  {   124  |   125  }
+                        126  ~   127 del */
+                     'x',
+                     'y', 'z', 0, '|', 0, '~', 0};
+
+  static const int8_t unhex[256] = {
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  -1, -1, -1, -1, -1, -1,
+      -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      -1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1};
+
+  char c, ch;
+  int8_t unhex_val;
+  const char *p = data;
+  const char *header_field_mark = 0;
+  const char *header_value_mark = 0;
+  const char *url_mark = 0;
+  const char *body_mark = 0;
+  const char *status_mark = 0;
+
+  /* We're in an error state. Don't bother doing anything. */
+  if (CROW_HTTP_PARSER_ERRNO(parser) != HPE_OK) {
+    return 0;
+  }
+
+  if (len == 0) {
+    switch (parser->state) {
+      case s_body_identity_eof:
+        /* Use of CROW_CALLBACK_NOTIFY() here would erroneously return 1 byte
+         * read if
+         * we got paused.
+         */
+        CROW_CALLBACK_NOTIFY_NOADVANCE(message_complete);
+        return 0;
+
+      case s_dead:
+      case s_start_req_or_res:
+      case s_start_res:
+      case s_start_req:
+        return 0;
+
+      default:
+        CROW_SET_ERRNO(HPE_INVALID_EOF_STATE);
+        return 1;
+    }
+  }
+
+  if (parser->state == s_header_field) header_field_mark = data;
+  if (parser->state == s_header_value) header_value_mark = data;
+  switch (parser->state) {
+    case s_req_path:
+    case s_req_schema:
+    case s_req_schema_slash:
+    case s_req_schema_slash_slash:
+    case s_req_server_start:
+    case s_req_server:
+    case s_req_server_with_at:
+    case s_req_query_string_start:
+    case s_req_query_string:
+    case s_req_fragment_start:
+    case s_req_fragment:
+      url_mark = data;
+      break;
+    case s_res_status:
+      status_mark = data;
+      break;
+  }
+
+  for (p = data; p != data + len; p++) {
+    ch = *p;
+
+    if (CROW_PARSING_HEADER(parser->state)) {
+      ++parser->nread;
+      /* Don't allow the total size of the HTTP headers (including the status
+       * line) to exceed CROW_HTTP_MAX_HEADER_SIZE.  This check is here to
+       * protect
+       * embedders against denial-of-service attacks where the attacker feeds
+       * us a never-ending header that the embedder keeps buffering.
+       *
+       * This check is arguably the responsibility of embedders but we're doing
+       * it on the embedder's behalf because most won't bother and this way we
+       * make the web a little safer.  CROW_HTTP_MAX_HEADER_SIZE is still far
+       * bigger
+       * than any reasonable request or response so this should never affect
+       * day-to-day operation.
+       */
+      if (parser->nread > (CROW_HTTP_MAX_HEADER_SIZE)) {
+        CROW_SET_ERRNO(HPE_HEADER_OVERFLOW);
+        goto error;
+      }
+    }
+
+  reexecute_byte:
+    switch (parser->state) {
+      case s_dead:
+        /* this state is used after a 'Connection: close' message
+         * the parser will error out if it reads another message
+         */
+        if (ch == CROW_CR || ch == CROW_LF) break;
+
+        CROW_SET_ERRNO(HPE_CLOSED_CONNECTION);
+        goto error;
+
+      case s_start_req_or_res: {
+        if (ch == CROW_CR || ch == CROW_LF) break;
+        parser->flags = 0;
+        parser->content_length = CROW_ULLONG_MAX;
+
+        if (ch == 'H') {
+          parser->state = s_res_or_resp_H;
+
+          CROW_CALLBACK_NOTIFY(message_begin);
+        } else {
+          parser->type = HTTP_REQUEST;
+          parser->state = s_start_req;
+          goto reexecute_byte;
+        }
+
+        break;
+      }
+
+      case s_res_or_resp_H:
+        if (ch == 'T') {
+          parser->type = HTTP_RESPONSE;
+          parser->state = s_res_HT;
+        } else {
+          if (ch != 'E') {
+            CROW_SET_ERRNO(HPE_INVALID_CONSTANT);
+            goto error;
+          }
+
+          parser->type = HTTP_REQUEST;
+          parser->method = HTTP_HEAD;
+          parser->index = 2;
+          parser->state = s_req_method;
+        }
+        break;
+
+      case s_start_res: {
+        parser->flags = 0;
+        parser->content_length = CROW_ULLONG_MAX;
+
+        switch (ch) {
+          case 'H':
+            parser->state = s_res_H;
+            break;
+
+          case CROW_CR:
+          case CROW_LF:
+            break;
+
+          default:
+            CROW_SET_ERRNO(HPE_INVALID_CONSTANT);
+            goto error;
+        }
+
+        CROW_CALLBACK_NOTIFY(message_begin);
+        break;
+      }
+
+      case s_res_H:
+        CROW_STRICT_CHECK(ch != 'T');
+        parser->state = s_res_HT;
+        break;
+
+      case s_res_HT:
+        CROW_STRICT_CHECK(ch != 'T');
+        parser->state = s_res_HTT;
+        break;
+
+      case s_res_HTT:
+        CROW_STRICT_CHECK(ch != 'P');
+        parser->state = s_res_HTTP;
+        break;
+
+      case s_res_HTTP:
+        CROW_STRICT_CHECK(ch != '/');
+        parser->state = s_res_first_http_major;
+        break;
+
+      case s_res_first_http_major:
+        if (ch < '0' || ch > '9') {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_major = ch - '0';
+        parser->state = s_res_http_major;
+        break;
+
+      /* major HTTP version or dot */
+      case s_res_http_major: {
+        if (ch == '.') {
+          parser->state = s_res_first_http_minor;
+          break;
+        }
+
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_major *= 10;
+        parser->http_major += ch - '0';
+
+        if (parser->http_major > 999) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        break;
+      }
+
+      /* first digit of minor HTTP version */
+      case s_res_first_http_minor:
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_minor = ch - '0';
+        parser->state = s_res_http_minor;
+        break;
+
+      /* minor HTTP version or end of request line */
+      case s_res_http_minor: {
+        if (ch == ' ') {
+          parser->state = s_res_first_status_code;
+          break;
+        }
+
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_minor *= 10;
+        parser->http_minor += ch - '0';
+
+        if (parser->http_minor > 999) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        break;
+      }
+
+      case s_res_first_status_code: {
+        if (!CROW_IS_NUM(ch)) {
+          if (ch == ' ') {
+            break;
+          }
+
+          CROW_SET_ERRNO(HPE_INVALID_STATUS);
+          goto error;
+        }
+        parser->status_code = ch - '0';
+        parser->state = s_res_status_code;
+        break;
+      }
+
+      case s_res_status_code: {
+        if (!CROW_IS_NUM(ch)) {
+          switch (ch) {
+            case ' ':
+              parser->state = s_res_status_start;
+              break;
+            case CROW_CR:
+              parser->state = s_res_line_almost_done;
+              break;
+            case CROW_LF:
+              parser->state = s_header_field_start;
+              break;
+            default:
+              CROW_SET_ERRNO(HPE_INVALID_STATUS);
+              goto error;
+          }
+          break;
+        }
+
+        parser->status_code *= 10;
+        parser->status_code += ch - '0';
+
+        if (parser->status_code > 999) {
+          CROW_SET_ERRNO(HPE_INVALID_STATUS);
+          goto error;
+        }
+
+        break;
+      }
+
+      case s_res_status_start: {
+        if (ch == CROW_CR) {
+          parser->state = s_res_line_almost_done;
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_field_start;
+          break;
+        }
+
+        CROW_MARK(status);
+        parser->state = s_res_status;
+        parser->index = 0;
+        break;
+      }
+
+      case s_res_status:
+        if (ch == CROW_CR) {
+          parser->state = s_res_line_almost_done;
+          CROW_CALLBACK_DATA(status);
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_field_start;
+          CROW_CALLBACK_DATA(status);
+          break;
+        }
+
+        break;
+
+      case s_res_line_almost_done:
+        CROW_STRICT_CHECK(ch != CROW_LF);
+        parser->state = s_header_field_start;
+        break;
+
+      case s_start_req: {
+        if (ch == CROW_CR || ch == CROW_LF) break;
+        parser->flags = 0;
+        parser->content_length = CROW_ULLONG_MAX;
+
+        if (!CROW_IS_ALPHA(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_METHOD);
+          goto error;
+        }
+
+        parser->method = (enum http_method)0;
+        parser->index = 1;
+        switch (ch) {
+          case 'C':
+            parser->method = HTTP_CONNECT; /* or COPY, CHECKOUT */
+            break;
+          case 'D':
+            parser->method = HTTP_DELETE;
+            break;
+          case 'G':
+            parser->method = HTTP_GET;
+            break;
+          case 'H':
+            parser->method = HTTP_HEAD;
+            break;
+          case 'L':
+            parser->method = HTTP_LOCK;
+            break;
+          case 'M':
+            parser->method = HTTP_MKCOL; /* or MOVE, MKACTIVITY, MERGE,
+                                            M-SEARCH, MKCALENDAR */
+            break;
+          case 'N':
+            parser->method = HTTP_NOTIFY;
+            break;
+          case 'O':
+            parser->method = HTTP_OPTIONS;
+            break;
+          case 'P':
+            parser->method = HTTP_POST;
+            /* or PROPFIND|PROPPATCH|PUT|PATCH|PURGE */
+            break;
+          case 'R':
+            parser->method = HTTP_REPORT;
+            break;
+          case 'S':
+            parser->method = HTTP_SUBSCRIBE; /* or SEARCH */
+            break;
+          case 'T':
+            parser->method = HTTP_TRACE;
+            break;
+          case 'U':
+            parser->method = HTTP_UNLOCK; /* or UNSUBSCRIBE */
+            break;
+          default:
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+        }
+        parser->state = s_req_method;
+
+        CROW_CALLBACK_NOTIFY(message_begin);
+
+        break;
+      }
+
+      case s_req_method: {
+        const char *matcher;
+        if (ch == '\0') {
+          CROW_SET_ERRNO(HPE_INVALID_METHOD);
+          goto error;
+        }
+
+        matcher = method_strings[parser->method];
+        if (ch == ' ' && matcher[parser->index] == '\0') {
+          parser->state = s_req_spaces_before_url;
+        } else if (ch == matcher[parser->index]) {
+          ; /* nada */
+        } else if (parser->method == HTTP_CONNECT) {
+          if (parser->index == 1 && ch == 'H') {
+            parser->method = HTTP_CHECKOUT;
+          } else if (parser->index == 2 && ch == 'P') {
+            parser->method = HTTP_COPY;
+          } else {
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+          }
+        } else if (parser->method == HTTP_MKCOL) {
+          if (parser->index == 1 && ch == 'O') {
+            parser->method = HTTP_MOVE;
+          } else if (parser->index == 1 && ch == 'E') {
+            parser->method = HTTP_MERGE;
+          } else if (parser->index == 1 && ch == '-') {
+            parser->method = HTTP_MSEARCH;
+          } else if (parser->index == 2 && ch == 'A') {
+            parser->method = HTTP_MKACTIVITY;
+          } else if (parser->index == 3 && ch == 'A') {
+            parser->method = HTTP_MKCALENDAR;
+          } else {
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+          }
+        } else if (parser->method == HTTP_SUBSCRIBE) {
+          if (parser->index == 1 && ch == 'E') {
+            parser->method = HTTP_SEARCH;
+          } else {
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+          }
+        } else if (parser->index == 1 && parser->method == HTTP_POST) {
+          if (ch == 'R') {
+            parser->method = HTTP_PROPFIND; /* or HTTP_PROPPATCH */
+          } else if (ch == 'U') {
+            parser->method = HTTP_PUT; /* or HTTP_PURGE */
+          } else if (ch == 'A') {
+            parser->method = HTTP_PATCH;
+          } else {
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+          }
+        } else if (parser->index == 2) {
+          if (parser->method == HTTP_PUT) {
+            if (ch == 'R') {
+              parser->method = HTTP_PURGE;
+            } else {
+              CROW_SET_ERRNO(HPE_INVALID_METHOD);
+              goto error;
+            }
+          } else if (parser->method == HTTP_UNLOCK) {
+            if (ch == 'S') {
+              parser->method = HTTP_UNSUBSCRIBE;
+            } else {
+              CROW_SET_ERRNO(HPE_INVALID_METHOD);
+              goto error;
+            }
+          } else {
+            CROW_SET_ERRNO(HPE_INVALID_METHOD);
+            goto error;
+          }
+        } else if (parser->index == 4 && parser->method == HTTP_PROPFIND &&
+                   ch == 'P') {
+          parser->method = HTTP_PROPPATCH;
+        } else {
+          CROW_SET_ERRNO(HPE_INVALID_METHOD);
+          goto error;
+        }
+
+        ++parser->index;
+        break;
+      }
+
+      case s_req_spaces_before_url: {
+        if (ch == ' ') break;
+
+        CROW_MARK(url);
+        if (parser->method == HTTP_CONNECT) {
+          parser->state = s_req_server_start;
+        }
+
+        parser->state = parse_url_char((enum state)parser->state, ch);
+        if (parser->state == s_dead) {
+          CROW_SET_ERRNO(HPE_INVALID_URL);
+          goto error;
+        }
+
+        break;
+      }
+
+      case s_req_schema:
+      case s_req_schema_slash:
+      case s_req_schema_slash_slash:
+      case s_req_server_start: {
+        switch (ch) {
+          /* No whitespace allowed here */
+          case ' ':
+          case CROW_CR:
+          case CROW_LF:
+            CROW_SET_ERRNO(HPE_INVALID_URL);
+            goto error;
+          default:
+            parser->state = parse_url_char((enum state)parser->state, ch);
+            if (parser->state == s_dead) {
+              CROW_SET_ERRNO(HPE_INVALID_URL);
+              goto error;
+            }
+        }
+
+        break;
+      }
+
+      case s_req_server:
+      case s_req_server_with_at:
+      case s_req_path:
+      case s_req_query_string_start:
+      case s_req_query_string:
+      case s_req_fragment_start:
+      case s_req_fragment: {
+        switch (ch) {
+          case ' ':
+            parser->state = s_req_http_start;
+            CROW_CALLBACK_DATA(url);
+            break;
+          case CROW_CR:
+          case CROW_LF:
+            parser->http_major = 0;
+            parser->http_minor = 9;
+            parser->state =
+                (ch == CROW_CR) ? s_req_line_almost_done : s_header_field_start;
+            CROW_CALLBACK_DATA(url);
+            break;
+          default:
+            parser->state = parse_url_char((enum state)parser->state, ch);
+            if (parser->state == s_dead) {
+              CROW_SET_ERRNO(HPE_INVALID_URL);
+              goto error;
+            }
+        }
+        break;
+      }
+
+      case s_req_http_start:
+        switch (ch) {
+          case 'H':
+            parser->state = s_req_http_H;
+            break;
+          case ' ':
+            break;
+          default:
+            CROW_SET_ERRNO(HPE_INVALID_CONSTANT);
+            goto error;
+        }
+        break;
+
+      case s_req_http_H:
+        CROW_STRICT_CHECK(ch != 'T');
+        parser->state = s_req_http_HT;
+        break;
+
+      case s_req_http_HT:
+        CROW_STRICT_CHECK(ch != 'T');
+        parser->state = s_req_http_HTT;
+        break;
+
+      case s_req_http_HTT:
+        CROW_STRICT_CHECK(ch != 'P');
+        parser->state = s_req_http_HTTP;
+        break;
+
+      case s_req_http_HTTP:
+        CROW_STRICT_CHECK(ch != '/');
+        parser->state = s_req_first_http_major;
+        break;
+
+      /* first digit of major HTTP version */
+      case s_req_first_http_major:
+        if (ch < '1' || ch > '9') {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_major = ch - '0';
+        parser->state = s_req_http_major;
+        break;
+
+      /* major HTTP version or dot */
+      case s_req_http_major: {
+        if (ch == '.') {
+          parser->state = s_req_first_http_minor;
+          break;
+        }
+
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_major *= 10;
+        parser->http_major += ch - '0';
+
+        if (parser->http_major > 999) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        break;
+      }
+
+      /* first digit of minor HTTP version */
+      case s_req_first_http_minor:
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_minor = ch - '0';
+        parser->state = s_req_http_minor;
+        break;
+
+      /* minor HTTP version or end of request line */
+      case s_req_http_minor: {
+        if (ch == CROW_CR) {
+          parser->state = s_req_line_almost_done;
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_field_start;
+          break;
+        }
+
+        /* XXX allow spaces after digit? */
+
+        if (!CROW_IS_NUM(ch)) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        parser->http_minor *= 10;
+        parser->http_minor += ch - '0';
+
+        if (parser->http_minor > 999) {
+          CROW_SET_ERRNO(HPE_INVALID_VERSION);
+          goto error;
+        }
+
+        break;
+      }
+
+      /* end of request line */
+      case s_req_line_almost_done: {
+        if (ch != CROW_LF) {
+          CROW_SET_ERRNO(HPE_LF_EXPECTED);
+          goto error;
+        }
+
+        parser->state = s_header_field_start;
+        break;
+      }
+
+      case s_header_field_start: {
+        if (ch == CROW_CR) {
+          parser->state = s_headers_almost_done;
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          /* they might be just sending \n instead of \r\n so this would be
+           * the second \n to denote the end of headers*/
+          parser->state = s_headers_almost_done;
+          goto reexecute_byte;
+        }
+
+        c = CROW_TOKEN(ch);
+
+        if (!c) {
+          CROW_SET_ERRNO(HPE_INVALID_HEADER_TOKEN);
+          goto error;
+        }
+
+        CROW_MARK(header_field);
+
+        parser->index = 0;
+        parser->state = s_header_field;
+
+        switch (c) {
+          case 'c':
+            parser->header_state = h_C;
+            break;
+
+          case 'p':
+            parser->header_state = h_matching_proxy_connection;
+            break;
+
+          case 't':
+            parser->header_state = h_matching_transfer_encoding;
+            break;
+
+          case 'u':
+            parser->header_state = h_matching_upgrade;
+            break;
+
+          default:
+            parser->header_state = h_general;
+            break;
+        }
+        break;
+      }
+
+      case s_header_field: {
+        c = CROW_TOKEN(ch);
+
+        if (c) {
+          switch (parser->header_state) {
+            case h_general:
+              break;
+
+            case h_C:
+              parser->index++;
+              parser->header_state = (c == 'o' ? h_CO : h_general);
+              break;
+
+            case h_CO:
+              parser->index++;
+              parser->header_state = (c == 'n' ? h_CON : h_general);
+              break;
+
+            case h_CON:
+              parser->index++;
+              switch (c) {
+                case 'n':
+                  parser->header_state = h_matching_connection;
+                  break;
+                case 't':
+                  parser->header_state = h_matching_content_length;
+                  break;
+                default:
+                  parser->header_state = h_general;
+                  break;
+              }
+              break;
+
+            /* connection */
+
+            case h_matching_connection:
+              parser->index++;
+              if (parser->index > sizeof(CROW_CONNECTION) - 1 ||
+                  c != CROW_CONNECTION[parser->index]) {
+                parser->header_state = h_general;
+              } else if (parser->index == sizeof(CROW_CONNECTION) - 2) {
+                parser->header_state = h_connection;
+              }
+              break;
+
+            /* proxy-connection */
+
+            case h_matching_proxy_connection:
+              parser->index++;
+              if (parser->index > sizeof(CROW_PROXY_CONNECTION) - 1 ||
+                  c != CROW_PROXY_CONNECTION[parser->index]) {
+                parser->header_state = h_general;
+              } else if (parser->index == sizeof(CROW_PROXY_CONNECTION) - 2) {
+                parser->header_state = h_connection;
+              }
+              break;
+
+            /* content-length */
+
+            case h_matching_content_length:
+              parser->index++;
+              if (parser->index > sizeof(CROW_CONTENT_LENGTH) - 1 ||
+                  c != CROW_CONTENT_LENGTH[parser->index]) {
+                parser->header_state = h_general;
+              } else if (parser->index == sizeof(CROW_CONTENT_LENGTH) - 2) {
+                parser->header_state = h_content_length;
+              }
+              break;
+
+            /* transfer-encoding */
+
+            case h_matching_transfer_encoding:
+              parser->index++;
+              if (parser->index > sizeof(CROW_TRANSFER_ENCODING) - 1 ||
+                  c != CROW_TRANSFER_ENCODING[parser->index]) {
+                parser->header_state = h_general;
+              } else if (parser->index == sizeof(CROW_TRANSFER_ENCODING) - 2) {
+                parser->header_state = h_transfer_encoding;
+              }
+              break;
+
+            /* upgrade */
+
+            case h_matching_upgrade:
+              parser->index++;
+              if (parser->index > sizeof(CROW_UPGRADE) - 1 ||
+                  c != CROW_UPGRADE[parser->index]) {
+                parser->header_state = h_general;
+              } else if (parser->index == sizeof(CROW_UPGRADE) - 2) {
+                parser->header_state = h_upgrade;
+              }
+              break;
+
+            case h_connection:
+            case h_content_length:
+            case h_transfer_encoding:
+            case h_upgrade:
+              if (ch != ' ') parser->header_state = h_general;
+              break;
+
+            default:
+              assert(0 && "Unknown header_state");
+              break;
+          }
+          break;
+        }
+
+        if (ch == ':') {
+          parser->state = s_header_value_discard_ws;
+          CROW_CALLBACK_DATA(header_field);
+          break;
+        }
+
+        if (ch == CROW_CR) {
+          parser->state = s_header_almost_done;
+          CROW_CALLBACK_DATA(header_field);
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_field_start;
+          CROW_CALLBACK_DATA(header_field);
+          break;
+        }
+
+        CROW_SET_ERRNO(HPE_INVALID_HEADER_TOKEN);
+        goto error;
+      }
+
+      case s_header_value_discard_ws:
+        if (ch == ' ' || ch == '\t') break;
+
+        if (ch == CROW_CR) {
+          parser->state = s_header_value_discard_ws_almost_done;
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_value_discard_lws;
+          break;
+        }
+
+      /* FALLTHROUGH */
+
+      case s_header_value_start: {
+        CROW_MARK(header_value);
+
+        parser->state = s_header_value;
+        parser->index = 0;
+
+        c = CROW_LOWER(ch);
+
+        switch (parser->header_state) {
+          case h_upgrade:
+            parser->flags |= F_UPGRADE;
+            parser->header_state = h_general;
+            break;
+
+          case h_transfer_encoding:
+            /* looking for 'Transfer-Encoding: chunked' */
+            if ('c' == c) {
+              parser->header_state = h_matching_transfer_encoding_chunked;
+            } else {
+              parser->header_state = h_general;
+            }
+            break;
+
+          case h_content_length:
+            if (!CROW_IS_NUM(ch)) {
+              CROW_SET_ERRNO(HPE_INVALID_CONTENT_LENGTH);
+              goto error;
+            }
+
+            parser->content_length = ch - '0';
+            break;
+
+          case h_connection:
+            /* looking for 'Connection: keep-alive' */
+            if (c == 'k') {
+              parser->header_state = h_matching_connection_keep_alive;
+              /* looking for 'Connection: close' */
+            } else if (c == 'c') {
+              parser->header_state = h_matching_connection_close;
+            } else {
+              parser->header_state = h_general;
+            }
+            break;
+
+          default:
+            parser->header_state = h_general;
+            break;
+        }
+        break;
+      }
+
+      case s_header_value: {
+        if (ch == CROW_CR) {
+          parser->state = s_header_almost_done;
+          CROW_CALLBACK_DATA(header_value);
+          break;
+        }
+
+        if (ch == CROW_LF) {
+          parser->state = s_header_almost_done;
+          CROW_CALLBACK_DATA_NOADVANCE(header_value);
+          goto reexecute_byte;
+        }
+
+        c = CROW_LOWER(ch);
+
+        switch (parser->header_state) {
+          case h_general:
+            break;
+
+          case h_connection:
+          case h_transfer_encoding:
+            assert(0 && "Shouldn't get here.");
+            break;
+
+          case h_content_length: {
+            uint64_t t;
+
+            if (ch == ' ') break;
+
+            if (!CROW_IS_NUM(ch)) {
+              CROW_SET_ERRNO(HPE_INVALID_CONTENT_LENGTH);
+              goto error;
+            }
+
+            t = parser->content_length;
+            t *= 10;
+            t += ch - '0';
+
+            /* Overflow? Test against a conservative limit for simplicity. */
+            if ((CROW_ULLONG_MAX - 10) / 10 < parser->content_length) {
+              CROW_SET_ERRNO(HPE_INVALID_CONTENT_LENGTH);
+              goto error;
+            }
+
+            parser->content_length = t;
+            break;
+          }
+
+          /* Transfer-Encoding: chunked */
+          case h_matching_transfer_encoding_chunked:
+            parser->index++;
+            if (parser->index > sizeof(CROW_CHUNKED) - 1 ||
+                c != CROW_CHUNKED[parser->index]) {
+              parser->header_state = h_general;
+            } else if (parser->index == sizeof(CROW_CHUNKED) - 2) {
+              parser->header_state = h_transfer_encoding_chunked;
+            }
+            break;
+
+          /* looking for 'Connection: keep-alive' */
+          case h_matching_connection_keep_alive:
+            parser->index++;
+            if (parser->index > sizeof(CROW_KEEP_ALIVE) - 1 ||
+                c != CROW_KEEP_ALIVE[parser->index]) {
+              parser->header_state = h_general;
+            } else if (parser->index == sizeof(CROW_KEEP_ALIVE) - 2) {
+              parser->header_state = h_connection_keep_alive;
+            }
+            break;
+
+          /* looking for 'Connection: close' */
+          case h_matching_connection_close:
+            parser->index++;
+            if (parser->index > sizeof(CROW_CLOSE) - 1 ||
+                c != CROW_CLOSE[parser->index]) {
+              parser->header_state = h_general;
+            } else if (parser->index == sizeof(CROW_CLOSE) - 2) {
+              parser->header_state = h_connection_close;
+            }
+            break;
+
+          case h_transfer_encoding_chunked:
+          case h_connection_keep_alive:
+          case h_connection_close:
+            if (ch != ' ') parser->header_state = h_general;
+            break;
+
+          default:
+            parser->state = s_header_value;
+            parser->header_state = h_general;
+            break;
+        }
+        break;
+      }
+
+      case s_header_almost_done: {
+        CROW_STRICT_CHECK(ch != CROW_LF);
+
+        parser->state = s_header_value_lws;
+        break;
+      }
+
+      case s_header_value_lws: {
+        if (ch == ' ' || ch == '\t') {
+          parser->state = s_header_value_start;
+          goto reexecute_byte;
+        }
+
+        /* finished the header */
+        switch (parser->header_state) {
+          case h_connection_keep_alive:
+            parser->flags |= F_CONNECTION_KEEP_ALIVE;
+            break;
+          case h_connection_close:
+            parser->flags |= F_CONNECTION_CLOSE;
+            break;
+          case h_transfer_encoding_chunked:
+            parser->flags |= F_CHUNKED;
+            break;
+          default:
+            break;
+        }
+
+        parser->state = s_header_field_start;
+        goto reexecute_byte;
+      }
+
+      case s_header_value_discard_ws_almost_done: {
+        CROW_STRICT_CHECK(ch != CROW_LF);
+        parser->state = s_header_value_discard_lws;
+        break;
+      }
+
+      case s_header_value_discard_lws: {
+        if (ch == ' ' || ch == '\t') {
+          parser->state = s_header_value_discard_ws;
+          break;
+        } else {
+          /* header value was empty */
+          CROW_MARK(header_value);
+          parser->state = s_header_field_start;
+          CROW_CALLBACK_DATA_NOADVANCE(header_value);
+          goto reexecute_byte;
+        }
+      }
+
+      case s_headers_almost_done: {
+        CROW_STRICT_CHECK(ch != CROW_LF);
+
+        if (parser->flags & F_TRAILING) {
+          /* End of a chunked request */
+          parser->state = CROW_NEW_MESSAGE();
+          CROW_CALLBACK_NOTIFY(message_complete);
+          break;
+        }
+
+        parser->state = s_headers_done;
+
+        /* Set this here so that on_headers_complete() callbacks can see it */
+        parser->upgrade =
+            (parser->flags & F_UPGRADE || parser->method == HTTP_CONNECT);
+
+        /* Here we call the headers_complete callback. This is somewhat
+         * different than other callbacks because if the user returns 1, we
+         * will interpret that as saying that this message has no body. This
+         * is needed for the annoying case of recieving a response to a HEAD
+         * request.
+         *
+         * We'd like to use CROW_CALLBACK_NOTIFY_NOADVANCE() here but we cannot,
+         * so
+         * we have to simulate it by handling a change in errno below.
+         */
+        if (settings->on_headers_complete) {
+          switch (settings->on_headers_complete(parser)) {
+            case 0:
+              break;
+
+            case 1:
+              parser->flags |= F_SKIPBODY;
+              break;
+
+            default:
+              CROW_SET_ERRNO(HPE_CB_headers_complete);
+              return p - data; /* Error */
+          }
+        }
+
+        if (CROW_HTTP_PARSER_ERRNO(parser) != HPE_OK) {
+          return p - data;
+        }
+
+        goto reexecute_byte;
+      }
+
+      case s_headers_done: {
+        CROW_STRICT_CHECK(ch != CROW_LF);
+
+        parser->nread = 0;
+
+        /* Exit, the rest of the connect is in a different protocol. */
+        if (parser->upgrade) {
+          parser->state = CROW_NEW_MESSAGE();
+          CROW_CALLBACK_NOTIFY(message_complete);
+          return (p - data) + 1;
+        }
+
+        if (parser->flags & F_SKIPBODY) {
+          parser->state = CROW_NEW_MESSAGE();
+          CROW_CALLBACK_NOTIFY(message_complete);
+        } else if (parser->flags & F_CHUNKED) {
+          /* chunked encoding - ignore Content-Length header */
+          parser->state = s_chunk_size_start;
+        } else {
+          if (parser->content_length == 0) {
+            /* Content-Length header given but zero: Content-Length: 0\r\n */
+            parser->state = CROW_NEW_MESSAGE();
+            CROW_CALLBACK_NOTIFY(message_complete);
+          } else if (parser->content_length != CROW_ULLONG_MAX) {
+            /* Content-Length header given and non-zero */
+            parser->state = s_body_identity;
+          } else {
+            if (parser->type == HTTP_REQUEST ||
+                !http_message_needs_eof(parser)) {
+              /* Assume content-length 0 - read the next */
+              parser->state = CROW_NEW_MESSAGE();
+              CROW_CALLBACK_NOTIFY(message_complete);
+            } else {
+              /* Read body until EOF */
+              parser->state = s_body_identity_eof;
+            }
+          }
+        }
+
+        break;
+      }
+
+      case s_body_identity: {
+        uint64_t to_read =
+            CROW_MIN(parser->content_length, (uint64_t)((data + len) - p));
+
+        assert(parser->content_length != 0 &&
+               parser->content_length != CROW_ULLONG_MAX);
+
+        /* The difference between advancing content_length and p is because
+         * the latter will automaticaly advance on the next loop iteration.
+         * Further, if content_length ends up at 0, we want to see the last
+         * byte again for our message complete callback.
+         */
+        CROW_MARK(body);
+        parser->content_length -= to_read;
+        p += to_read - 1;
+
+        if (parser->content_length == 0) {
+          parser->state = s_message_done;
+
+          /* Mimic CROW_CALLBACK_DATA_NOADVANCE() but with one extra byte.
+           *
+           * The alternative to doing this is to wait for the next byte to
+           * trigger the data callback, just as in every other case. The
+           * problem with this is that this makes it difficult for the test
+           * harness to distinguish between complete-on-EOF and
+           * complete-on-length. It's not clear that this distinction is
+           * important for applications, but let's keep it for now.
+           */
+          CROW_CALLBACK_DATA_(body, p - body_mark + 1, p - data);
+          goto reexecute_byte;
+        }
+
+        break;
+      }
+
+      /* read until EOF */
+      case s_body_identity_eof:
+        CROW_MARK(body);
+        p = data + len - 1;
+
+        break;
+
+      case s_message_done:
+        parser->state = CROW_NEW_MESSAGE();
+        CROW_CALLBACK_NOTIFY(message_complete);
+        break;
+
+      case s_chunk_size_start: {
+        assert(parser->nread == 1);
+        assert(parser->flags & F_CHUNKED);
+
+        unhex_val = unhex[(unsigned char)ch];
+        if (unhex_val == -1) {
+          CROW_SET_ERRNO(HPE_INVALID_CHUNK_SIZE);
+          goto error;
+        }
+
+        parser->content_length = unhex_val;
+        parser->state = s_chunk_size;
+        break;
+      }
+
+      case s_chunk_size: {
+        uint64_t t;
+
+        assert(parser->flags & F_CHUNKED);
+
+        if (ch == CROW_CR) {
+          parser->state = s_chunk_size_almost_done;
+          break;
+        }
+
+        unhex_val = unhex[(unsigned char)ch];
+
+        if (unhex_val == -1) {
+          if (ch == ';' || ch == ' ') {
+            parser->state = s_chunk_parameters;
+            break;
+          }
+
+          CROW_SET_ERRNO(HPE_INVALID_CHUNK_SIZE);
+          goto error;
+        }
+
+        t = parser->content_length;
+        t *= 16;
+        t += unhex_val;
+
+        /* Overflow? Test against a conservative limit for simplicity. */
+        if ((CROW_ULLONG_MAX - 16) / 16 < parser->content_length) {
+          CROW_SET_ERRNO(HPE_INVALID_CONTENT_LENGTH);
+          goto error;
+        }
+
+        parser->content_length = t;
+        break;
+      }
+
+      case s_chunk_parameters: {
+        assert(parser->flags & F_CHUNKED);
+        /* just ignore this shit. TODO check for overflow */
+        if (ch == CROW_CR) {
+          parser->state = s_chunk_size_almost_done;
+          break;
+        }
+        break;
+      }
+
+      case s_chunk_size_almost_done: {
+        assert(parser->flags & F_CHUNKED);
+        CROW_STRICT_CHECK(ch != CROW_LF);
+
+        parser->nread = 0;
+
+        if (parser->content_length == 0) {
+          parser->flags |= F_TRAILING;
+          parser->state = s_header_field_start;
+        } else {
+          parser->state = s_chunk_data;
+        }
+        break;
+      }
+
+      case s_chunk_data: {
+        uint64_t to_read =
+            CROW_MIN(parser->content_length, (uint64_t)((data + len) - p));
+
+        assert(parser->flags & F_CHUNKED);
+        assert(parser->content_length != 0 &&
+               parser->content_length != CROW_ULLONG_MAX);
+
+        /* See the explanation in s_body_identity for why the content
+         * length and data pointers are managed this way.
+         */
+        CROW_MARK(body);
+        parser->content_length -= to_read;
+        p += to_read - 1;
+
+        if (parser->content_length == 0) {
+          parser->state = s_chunk_data_almost_done;
+        }
+
+        break;
+      }
+
+      case s_chunk_data_almost_done:
+        assert(parser->flags & F_CHUNKED);
+        assert(parser->content_length == 0);
+        CROW_STRICT_CHECK(ch != CROW_CR);
+        parser->state = s_chunk_data_done;
+        CROW_CALLBACK_DATA(body);
+        break;
+
+      case s_chunk_data_done:
+        assert(parser->flags & F_CHUNKED);
+        CROW_STRICT_CHECK(ch != CROW_LF);
+        parser->nread = 0;
+        parser->state = s_chunk_size_start;
+        break;
+
+      default:
+        assert(0 && "unhandled state");
+        CROW_SET_ERRNO(HPE_INVALID_INTERNAL_STATE);
+        goto error;
+    }
+  }
+
+  /* Run callbacks for any marks that we have leftover after we ran our of
+   * bytes. There should be at most one of these set, so it's OK to invoke
+   * them in series (unset marks will not result in callbacks).
+   *
+   * We use the NOADVANCE() variety of callbacks here because 'p' has already
+   * overflowed 'data' and this allows us to correct for the off-by-one that
+   * we'd otherwise have (since CROW_CALLBACK_DATA() is meant to be run with a
+   * 'p'
+   * value that's in-bounds).
+   */
+
+  assert(((header_field_mark ? 1 : 0) + (header_value_mark ? 1 : 0) +
+          (url_mark ? 1 : 0) + (body_mark ? 1 : 0) + (status_mark ? 1 : 0)) <=
+         1);
+
+  CROW_CALLBACK_DATA_NOADVANCE(header_field);
+  CROW_CALLBACK_DATA_NOADVANCE(header_value);
+  CROW_CALLBACK_DATA_NOADVANCE(url);
+  CROW_CALLBACK_DATA_NOADVANCE(body);
+  CROW_CALLBACK_DATA_NOADVANCE(status);
+
+  return len;
+
+error:
+  if (CROW_HTTP_PARSER_ERRNO(parser) == HPE_OK) {
+    CROW_SET_ERRNO(HPE_UNKNOWN);
+  }
+
+  return (p - data);
+}
+
+/* Does the parser need to see an EOF to find the end of the message? */
+inline int http_message_needs_eof(const http_parser *parser) {
+  if (parser->type == HTTP_REQUEST) {
+    return 0;
+  }
+
+  /* See RFC 2616 section 4.4 */
+  if (parser->status_code / 100 == 1 || /* 1xx e.g. Continue */
+      parser->status_code == 204 ||     /* No Content */
+      parser->status_code == 304 ||     /* Not Modified */
+      parser->flags & F_SKIPBODY) {     /* response to a HEAD request */
+    return 0;
+  }
+
+  if ((parser->flags & F_CHUNKED) ||
+      parser->content_length != CROW_ULLONG_MAX) {
+    return 0;
+  }
+
+  return 1;
+}
+
+inline int http_should_keep_alive(const http_parser *parser) {
+  if (parser->http_major > 0 && parser->http_minor > 0) {
+    /* HTTP/1.1 */
+    if (parser->flags & F_CONNECTION_CLOSE) {
+      return 0;
+    }
+  } else {
+    /* HTTP/1.0 or earlier */
+    if (!(parser->flags & F_CONNECTION_KEEP_ALIVE)) {
+      return 0;
+    }
+  }
+
+  return !http_message_needs_eof(parser);
+}
+
+inline const char *http_method_str(enum http_method m) {
+  static const char *method_strings[] = {
+#define CROW_XX(num, name, string) #string,
+      CROW_HTTP_METHOD_MAP(CROW_XX)
+#undef CROW_XX
+  };
+  return CROW_ELEM_AT(method_strings, m, "<unknown>");
+}
+
+inline void http_parser_init(http_parser *parser, enum http_parser_type t) {
+  void *data = parser->data; /* preserve application data */
+  memset(parser, 0, sizeof(*parser));
+  parser->data = data;
+  parser->type = t;
+  parser->state =
+      (t == HTTP_REQUEST
+           ? s_start_req
+           : (t == HTTP_RESPONSE ? s_start_res : s_start_req_or_res));
+  parser->http_errno = HPE_OK;
+}
+
+inline const char *http_errno_name(enum http_errno err) {
+/* Map errno values to strings for human-readable output */
+#define CROW_HTTP_STRERROR_GEN(n, s) {"HPE_" #n, s},
+  static struct {
+    const char *name;
+    const char *description;
+  } http_strerror_tab[] = {CROW_HTTP_ERRNO_MAP(CROW_HTTP_STRERROR_GEN)};
+#undef CROW_HTTP_STRERROR_GEN
+  assert(err < (sizeof(http_strerror_tab) / sizeof(http_strerror_tab[0])));
+  return http_strerror_tab[err].name;
+}
+
+inline const char *http_errno_description(enum http_errno err) {
+/* Map errno values to strings for human-readable output */
+#define CROW_HTTP_STRERROR_GEN(n, s) {"HPE_" #n, s},
+  static struct {
+    const char *name;
+    const char *description;
+  } http_strerror_tab[] = {CROW_HTTP_ERRNO_MAP(CROW_HTTP_STRERROR_GEN)};
+#undef CROW_HTTP_STRERROR_GEN
+  assert(err < (sizeof(http_strerror_tab) / sizeof(http_strerror_tab[0])));
+  return http_strerror_tab[err].description;
+}
+
+inline static enum http_host_state http_parse_host_char(enum http_host_state s,
+                                                        const char ch) {
+  switch (s) {
+    case s_http_userinfo:
+    case s_http_userinfo_start:
+      if (ch == '@') {
+        return s_http_host_start;
+      }
+
+      if (CROW_IS_USERINFO_CHAR(ch)) {
+        return s_http_userinfo;
+      }
+      break;
+
+    case s_http_host_start:
+      if (ch == '[') {
+        return s_http_host_v6_start;
+      }
+
+      if (CROW_IS_HOST_CHAR(ch)) {
+        return s_http_host;
+      }
+
+      break;
+
+    case s_http_host:
+      if (CROW_IS_HOST_CHAR(ch)) {
+        return s_http_host;
+      }
+
+    /* FALLTHROUGH */
+    case s_http_host_v6_end:
+      if (ch == ':') {
+        return s_http_host_port_start;
+      }
+
+      break;
+
+    case s_http_host_v6:
+      if (ch == ']') {
+        return s_http_host_v6_end;
+      }
+
+    /* FALLTHROUGH */
+    case s_http_host_v6_start:
+      if (CROW_IS_HEX(ch) || ch == ':' || ch == '.') {
+        return s_http_host_v6;
+      }
+
+      break;
+
+    case s_http_host_port:
+    case s_http_host_port_start:
+      if (CROW_IS_NUM(ch)) {
+        return s_http_host_port;
+      }
+
+      break;
+
+    default:
+      break;
+  }
+  return s_http_host_dead;
+}
+
+inline int http_parse_host(const char *buf, struct http_parser_url *u,
+                           int found_at) {
+  enum http_host_state s;
+
+  const char *p;
+  size_t buflen = u->field_data[UF_HOST].off + u->field_data[UF_HOST].len;
+
+  u->field_data[UF_HOST].len = 0;
+
+  s = found_at ? s_http_userinfo_start : s_http_host_start;
+
+  for (p = buf + u->field_data[UF_HOST].off; p < buf + buflen; p++) {
+    enum http_host_state new_s = http_parse_host_char(s, *p);
+
+    if (new_s == s_http_host_dead) {
+      return 1;
+    }
+
+    switch (new_s) {
+      case s_http_host:
+        if (s != s_http_host) {
+          u->field_data[UF_HOST].off = p - buf;
+        }
+        u->field_data[UF_HOST].len++;
+        break;
+
+      case s_http_host_v6:
+        if (s != s_http_host_v6) {
+          u->field_data[UF_HOST].off = p - buf;
+        }
+        u->field_data[UF_HOST].len++;
+        break;
+
+      case s_http_host_port:
+        if (s != s_http_host_port) {
+          u->field_data[UF_PORT].off = p - buf;
+          u->field_data[UF_PORT].len = 0;
+          u->field_set |= (1 << UF_PORT);
+        }
+        u->field_data[UF_PORT].len++;
+        break;
+
+      case s_http_userinfo:
+        if (s != s_http_userinfo) {
+          u->field_data[UF_USERINFO].off = p - buf;
+          u->field_data[UF_USERINFO].len = 0;
+          u->field_set |= (1 << UF_USERINFO);
+        }
+        u->field_data[UF_USERINFO].len++;
+        break;
+
+      default:
+        break;
+    }
+    s = new_s;
+  }
+
+  /* Make sure we don't end somewhere unexpected */
+  switch (s) {
+    case s_http_host_start:
+    case s_http_host_v6_start:
+    case s_http_host_v6:
+    case s_http_host_port_start:
+    case s_http_userinfo:
+    case s_http_userinfo_start:
+      return 1;
+    default:
+      break;
+  }
+
+  return 0;
+}
+
+inline int http_parser_parse_url(const char *buf, size_t buflen, int is_connect,
+                                 struct http_parser_url *u) {
+  enum state s;
+  const char *p;
+  enum http_parser_url_fields uf, old_uf;
+  int found_at = 0;
+
+  u->port = u->field_set = 0;
+  s = is_connect ? s_req_server_start : s_req_spaces_before_url;
+  old_uf = UF_MAX;
+
+  for (p = buf; p < buf + buflen; p++) {
+    s = parse_url_char(s, *p);
+
+    /* Figure out the next field that we're operating on */
+    switch (s) {
+      case s_dead:
+        return 1;
+
+      /* Skip delimeters */
+      case s_req_schema_slash:
+      case s_req_schema_slash_slash:
+      case s_req_server_start:
+      case s_req_query_string_start:
+      case s_req_fragment_start:
+        continue;
+
+      case s_req_schema:
+        uf = UF_SCHEMA;
+        break;
+
+      case s_req_server_with_at:
+        found_at = 1;
+
+      /* FALLTROUGH */
+      case s_req_server:
+        uf = UF_HOST;
+        break;
+
+      case s_req_path:
+        uf = UF_PATH;
+        break;
+
+      case s_req_query_string:
+        uf = UF_QUERY;
+        break;
+
+      case s_req_fragment:
+        uf = UF_FRAGMENT;
+        break;
+
+      default:
+        assert(!"Unexpected state");
+        return 1;
+    }
+
+    /* Nothing's changed; soldier on */
+    if (uf == old_uf) {
+      u->field_data[uf].len++;
+      continue;
+    }
+
+    u->field_data[uf].off = p - buf;
+    u->field_data[uf].len = 1;
+
+    u->field_set |= (1 << uf);
+    old_uf = uf;
+  }
+
+  /* host must be present if there is a schema */
+  /* parsing http:///toto will fail */
+  if ((u->field_set & ((1 << UF_SCHEMA) | (1 << UF_HOST))) != 0) {
+    if (http_parse_host(buf, u, found_at) != 0) {
+      return 1;
+    }
+  }
+
+  /* CONNECT requests can only contain "hostname:port" */
+  if (is_connect && u->field_set != ((1 << UF_HOST) | (1 << UF_PORT))) {
+    return 1;
+  }
+
+  if (u->field_set & (1 << UF_PORT)) {
+    /* Don't bother with endp; we've already validated the string */
+    unsigned long v = strtoul(buf + u->field_data[UF_PORT].off, NULL, 10);
+
+    /* Ports have a max value of 2^16 */
+    if (v > 0xffff) {
+      return 1;
+    }
+
+    u->port = (uint16_t)v;
+  }
+
+  return 0;
+}
+
+inline void http_parser_pause(http_parser *parser, int paused) {
+  /* Users should only be pausing/unpausing a parser that is not in an error
+   * state. In non-debug builds, there's not much that we can do about this
+   * other than ignore it.
+   */
+  if (CROW_HTTP_PARSER_ERRNO(parser) == HPE_OK ||
+      CROW_HTTP_PARSER_ERRNO(parser) == HPE_PAUSED) {
+    CROW_SET_ERRNO((paused) ? HPE_PAUSED : HPE_OK);
+  } else {
+    assert(0 && "Attempting to pause parser in error state");
+  }
+}
+
+inline int http_body_is_final(const struct http_parser *parser) {
+  return parser->state == s_message_done;
+}
+
+inline unsigned long http_parser_version(void) {
+  return CROW_HTTP_PARSER_VERSION_MAJOR * 0x10000 |
+         CROW_HTTP_PARSER_VERSION_MINOR * 0x00100 |
+         CROW_HTTP_PARSER_VERSION_PATCH * 0x00001;
+}
+
+#undef CROW_HTTP_METHOD_MAP
+#undef CROW_HTTP_ERRNO_MAP
+#undef CROW_SET_ERRNO
+#undef CROW_CALLBACK_NOTIFY_
+#undef CROW_CALLBACK_NOTIFY
+#undef CROW_CALLBACK_NOTIFY_NOADVANCE
+#undef CROW_CALLBACK_DATA_
+#undef CROW_CALLBACK_DATA
+#undef CROW_CALLBACK_DATA_NOADVANCE
+#undef CROW_MARK
+#undef CROW_PROXY_CONNECTION
+#undef CROW_CONNECTION
+#undef CROW_CONTENT_LENGTH
+#undef CROW_TRANSFER_ENCODING
+#undef CROW_UPGRADE
+#undef CROW_CHUNKED
+#undef CROW_KEEP_ALIVE
+#undef CROW_CLOSE
+#undef CROW_PARSING_HEADER
+#undef CROW_CR
+#undef CROW_LF
+#undef CROW_LOWER
+#undef CROW_IS_ALPHA
+#undef CROW_IS_NUM
+#undef CROW_IS_ALPHANUM
+#undef CROW_IS_HEX
+#undef CROW_IS_MARK
+#undef CROW_IS_USERINFO_CHAR
+#undef CROW_TOKEN
+#undef CROW_IS_URL_CHAR
+#undef CROW_IS_HOST_CHAR
+#undef CROW_start_state
+#undef CROW_STRICT_CHECK
+#undef CROW_NEW_MESSAGE
+
+#ifdef __cplusplus
+}
+#endif
+#endif
diff --git a/crow/include/crow/http_request.h b/crow/include/crow/http_request.h
new file mode 100644
index 0000000..354f997
--- /dev/null
+++ b/crow/include/crow/http_request.h
@@ -0,0 +1,62 @@
+#pragma once
+
+#include <boost/asio.hpp>
+
+#include "crow/ci_map.h"
+#include "crow/common.h"
+#include "crow/query_string.h"
+
+namespace crow {
+template <typename T>
+inline const std::string& get_header_value(const T& headers,
+                                           const std::string& key) {
+  if (headers.count(key)) {
+    return headers.find(key)->second;
+  }
+  static std::string empty;
+  return empty;
+}
+
+struct DetachHelper;
+
+struct request {
+  HTTPMethod method;
+  std::string raw_url;
+  std::string url;
+  query_string url_params;
+  ci_map headers;
+  std::string body;
+
+  void* middleware_context{};
+  boost::asio::io_service* io_service{};
+
+  request() : method(HTTPMethod::Get) {}
+
+  request(HTTPMethod method, std::string raw_url, std::string url,
+          query_string url_params, ci_map headers, std::string body)
+      : method(method),
+        raw_url(std::move(raw_url)),
+        url(std::move(url)),
+        url_params(std::move(url_params)),
+        headers(std::move(headers)),
+        body(std::move(body)) {}
+
+  void add_header(std::string key, std::string value) {
+    headers.emplace(std::move(key), std::move(value));
+  }
+
+  const std::string& get_header_value(const std::string& key) const {
+    return crow::get_header_value(headers, key);
+  }
+
+  template <typename CompletionHandler>
+  void post(CompletionHandler handler) {
+    io_service->post(handler);
+  }
+
+  template <typename CompletionHandler>
+  void dispatch(CompletionHandler handler) {
+    io_service->dispatch(handler);
+  }
+};
+}
diff --git a/crow/include/crow/http_response.h b/crow/include/crow/http_response.h
new file mode 100644
index 0000000..66d2ee3
--- /dev/null
+++ b/crow/include/crow/http_response.h
@@ -0,0 +1,100 @@
+#pragma once
+#include <string>
+#include <unordered_map>
+
+#include "crow/ci_map.h"
+#include "crow/http_request.h"
+#include "crow/json.h"
+
+namespace crow {
+template <typename Adaptor, typename Handler, typename... Middlewares>
+class Connection;
+struct response {
+  template <typename Adaptor, typename Handler, typename... Middlewares>
+  friend class crow::Connection;
+
+  int code{200};
+  std::string body;
+  json::wvalue json_value;
+
+  // `headers' stores HTTP headers.
+  ci_map headers;
+
+  void set_header(std::string key, std::string value) {
+    headers.erase(key);
+    headers.emplace(std::move(key), std::move(value));
+  }
+  void add_header(std::string key, std::string value) {
+    headers.emplace(std::move(key), std::move(value));
+  }
+
+  const std::string& get_header_value(const std::string& key) {
+    return crow::get_header_value(headers, key);
+  }
+
+  response() {}
+  explicit response(int code) : code(code) {}
+  response(std::string body) : body(std::move(body)) {}
+  response(json::wvalue&& json_value) : json_value(std::move(json_value)) {
+    json_mode();
+  }
+  response(int code, std::string body) : code(code), body(std::move(body)) {}
+  response(const json::wvalue& json_value) : body(json::dump(json_value)) {
+    json_mode();
+  }
+  response(int code, const json::wvalue& json_value)
+      : code(code), body(json::dump(json_value)) {
+    json_mode();
+  }
+
+  response(response&& r) { *this = std::move(r); }
+
+  response& operator=(const response& r) = delete;
+
+  response& operator=(response&& r) noexcept {
+    body = std::move(r.body);
+    json_value = std::move(r.json_value);
+    code = r.code;
+    headers = std::move(r.headers);
+    completed_ = r.completed_;
+    return *this;
+  }
+
+  bool is_completed() const noexcept { return completed_; }
+
+  void clear() {
+    body.clear();
+    json_value.clear();
+    code = 200;
+    headers.clear();
+    completed_ = false;
+  }
+
+  void write(const std::string& body_part) { body += body_part; }
+
+  void end() {
+    if (!completed_) {
+      completed_ = true;
+
+      if (complete_request_handler_) {
+        complete_request_handler_();
+      }
+    }
+  }
+
+  void end(const std::string& body_part) {
+    body += body_part;
+    end();
+  }
+
+  bool is_alive() { return is_alive_helper_ && is_alive_helper_(); }
+
+ private:
+  bool completed_{};
+  std::function<void()> complete_request_handler_;
+  std::function<bool()> is_alive_helper_;
+
+  // In case of a JSON object, set the Content-Type header
+  void json_mode() { set_header("Content-Type", "application/json"); }
+};
+}
diff --git a/crow/include/crow/http_server.h b/crow/include/crow/http_server.h
new file mode 100644
index 0000000..363d268
--- /dev/null
+++ b/crow/include/crow/http_server.h
@@ -0,0 +1,205 @@
+#pragma once
+
+#include <boost/asio.hpp>
+#include <boost/date_time/posix_time/posix_time.hpp>
+#include <chrono>
+#ifdef CROW_ENABLE_SSL
+#include <boost/asio/ssl.hpp>
+#endif
+#include <atomic>
+#include <cstdint>
+#include <future>
+#include <vector>
+
+#include <memory>
+
+#include "crow/dumb_timer_queue.h"
+#include "crow/http_connection.h"
+#include "crow/logging.h"
+
+namespace crow {
+using namespace boost;
+using tcp = asio::ip::tcp;
+
+template <typename Handler, typename Adaptor = SocketAdaptor,
+          typename... Middlewares>
+class Server {
+ public:
+  Server(Handler* handler, std::string bindaddr, uint16_t port,
+         std::tuple<Middlewares...>* middlewares = nullptr,
+         uint16_t concurrency = 1,
+         typename Adaptor::context* adaptor_ctx = nullptr)
+      : acceptor_(io_service_,
+                  tcp::endpoint(boost::asio::ip::address::from_string(bindaddr),
+                                port)),
+        signals_(io_service_, SIGINT, SIGTERM),
+        tick_timer_(io_service_),
+        handler_(handler),
+        concurrency_(concurrency),
+        port_(port),
+        bindaddr_(bindaddr),
+        middlewares_(middlewares),
+        adaptor_ctx_(adaptor_ctx) {}
+
+  void set_tick_function(std::chrono::milliseconds d, std::function<void()> f) {
+    tick_interval_ = d;
+    tick_function_ = f;
+  }
+
+  void on_tick() {
+    tick_function_();
+    tick_timer_.expires_from_now(
+        boost::posix_time::milliseconds(tick_interval_.count()));
+    tick_timer_.async_wait([this](const boost::system::error_code& ec) {
+      if (ec) return;
+      on_tick();
+    });
+  }
+
+  void run() {
+    if (concurrency_ < 0) concurrency_ = 1;
+
+    for (int i = 0; i < concurrency_; i++)
+      io_service_pool_.emplace_back(new boost::asio::io_service());
+    get_cached_date_str_pool_.resize(concurrency_);
+    timer_queue_pool_.resize(concurrency_);
+
+    std::vector<std::future<void>> v;
+    std::atomic<int> init_count(0);
+    for (uint16_t i = 0; i < concurrency_; i++)
+      v.push_back(std::async(std::launch::async, [this, i, &init_count] {
+
+        // thread local date string get function
+        auto last = std::chrono::steady_clock::now();
+
+        std::string date_str;
+        auto update_date_str = [&] {
+          auto last_time_t = time(0);
+          tm my_tm;
+
+#ifdef _MSC_VER
+          gmtime_s(&my_tm, &last_time_t);
+#else
+                                gmtime_r(&last_time_t, &my_tm);
+#endif
+          date_str.resize(100);
+          size_t date_str_sz =
+              strftime(&date_str[0], 99, "%a, %d %b %Y %H:%M:%S GMT", &my_tm);
+          date_str.resize(date_str_sz);
+        };
+        update_date_str();
+        get_cached_date_str_pool_[i] = [&]() -> std::string {
+          if (std::chrono::steady_clock::now() - last >=
+              std::chrono::seconds(1)) {
+            last = std::chrono::steady_clock::now();
+            update_date_str();
+          }
+          return date_str;
+        };
+
+        // initializing timer queue
+        detail::dumb_timer_queue timer_queue;
+        timer_queue_pool_[i] = &timer_queue;
+
+        timer_queue.set_io_service(*io_service_pool_[i]);
+        boost::asio::deadline_timer timer(*io_service_pool_[i]);
+        timer.expires_from_now(boost::posix_time::seconds(1));
+
+        std::function<void(const boost::system::error_code& ec)> handler;
+        handler = [&](const boost::system::error_code& ec) {
+          if (ec) return;
+          timer_queue.process();
+          timer.expires_from_now(boost::posix_time::seconds(1));
+          timer.async_wait(handler);
+        };
+        timer.async_wait(handler);
+
+        init_count++;
+        try {
+          io_service_pool_[i]->run();
+        } catch (std::exception& e) {
+          CROW_LOG_ERROR << "Worker Crash: An uncaught exception occurred: "
+                         << e.what();
+        }
+      }));
+
+    if (tick_function_ && tick_interval_.count() > 0) {
+      tick_timer_.expires_from_now(
+          boost::posix_time::milliseconds(tick_interval_.count()));
+      tick_timer_.async_wait([this](const boost::system::error_code& ec) {
+        if (ec) return;
+        on_tick();
+      });
+    }
+
+    CROW_LOG_INFO << server_name_ << " server is running, local port " << port_;
+
+    signals_.async_wait([&](const boost::system::error_code& /*error*/,
+                            int /*signal_number*/) { stop(); });
+
+    while (concurrency_ != init_count) std::this_thread::yield();
+
+    do_accept();
+
+    std::thread([this] {
+      io_service_.run();
+      CROW_LOG_INFO << "Exiting.";
+    }).join();
+  }
+
+  void stop() {
+    io_service_.stop();
+    for (auto& io_service : io_service_pool_) io_service->stop();
+  }
+
+ private:
+  asio::io_service& pick_io_service() {
+    // TODO load balancing
+    roundrobin_index_++;
+    if (roundrobin_index_ >= io_service_pool_.size()) roundrobin_index_ = 0;
+    return *io_service_pool_[roundrobin_index_];
+  }
+
+  void do_accept() {
+    asio::io_service& is = pick_io_service();
+    auto p = new Connection<Adaptor, Handler, Middlewares...>(
+        is, handler_, server_name_, middlewares_,
+        get_cached_date_str_pool_[roundrobin_index_],
+        *timer_queue_pool_[roundrobin_index_], adaptor_ctx_);
+    acceptor_.async_accept(p->socket(),
+                           [this, p, &is](boost::system::error_code ec) {
+                             if (!ec) {
+                               is.post([p] { p->start(); });
+                             }
+                             do_accept();
+                           });
+  }
+
+ private:
+  asio::io_service io_service_;
+  std::vector<std::unique_ptr<asio::io_service>> io_service_pool_;
+  std::vector<detail::dumb_timer_queue*> timer_queue_pool_;
+  std::vector<std::function<std::string()>> get_cached_date_str_pool_;
+  tcp::acceptor acceptor_;
+  boost::asio::signal_set signals_;
+  boost::asio::deadline_timer tick_timer_;
+
+  Handler* handler_;
+  uint16_t concurrency_{1};
+  std::string server_name_ = "Crow/0.1";
+  uint16_t port_;
+  std::string bindaddr_;
+  unsigned int roundrobin_index_{};
+
+  std::chrono::milliseconds tick_interval_;
+  std::function<void()> tick_function_;
+
+  std::tuple<Middlewares...>* middlewares_;
+
+#ifdef CROW_ENABLE_SSL
+  bool use_ssl_{false};
+  boost::asio::ssl::context ssl_context_{boost::asio::ssl::context::sslv23};
+#endif
+  typename Adaptor::context* adaptor_ctx_;
+};
+}
diff --git a/crow/include/crow/json.h b/crow/include/crow/json.h
new file mode 100644
index 0000000..f368eb1
--- /dev/null
+++ b/crow/include/crow/json.h
@@ -0,0 +1,1217 @@
+#pragma once
+
+//#define CROW_JSON_NO_ERROR_CHECK
+
+#include <algorithm>
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/lexical_cast.hpp>
+#include <boost/operators.hpp>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <unordered_map>
+#include <vector>
+
+#include "crow/settings.h"
+
+#if defined(__GNUG__) || defined(__clang__)
+#define crow_json_likely(x) __builtin_expect(x, 1)
+#define crow_json_unlikely(x) __builtin_expect(x, 0)
+#else
+#define crow_json_likely(x) x
+#define crow_json_unlikely(x) x
+#endif
+
+namespace crow {
+namespace mustache {
+class template_t;
+}
+
+namespace json {
+inline void escape(const std::string& str, std::string& ret) {
+  ret.reserve(ret.size() + str.size() + str.size() / 4);
+  for (char c : str) {
+    switch (c) {
+      case '"':
+        ret += "\\\"";
+        break;
+      case '\\':
+        ret += "\\\\";
+        break;
+      case '\n':
+        ret += "\\n";
+        break;
+      case '\b':
+        ret += "\\b";
+        break;
+      case '\f':
+        ret += "\\f";
+        break;
+      case '\r':
+        ret += "\\r";
+        break;
+      case '\t':
+        ret += "\\t";
+        break;
+      default:
+        if (0 <= c && c < 0x20) {
+          ret += "\\u00";
+          auto to_hex = [](char c) {
+            c = c & 0xf;
+            if (c < 10) return '0' + c;
+            return 'a' + c - 10;
+          };
+          ret += to_hex(c / 16);
+          ret += to_hex(c % 16);
+        } else
+          ret += c;
+        break;
+    }
+  }
+}
+inline std::string escape(const std::string& str) {
+  std::string ret;
+  escape(str, ret);
+  return ret;
+}
+
+enum class type : char {
+  Null,
+  False,
+  True,
+  Number,
+  String,
+  List,
+  Object,
+};
+
+inline const char* get_type_str(type t) {
+  switch (t) {
+    case type::Number:
+      return "Number";
+    case type::False:
+      return "False";
+    case type::True:
+      return "True";
+    case type::List:
+      return "List";
+    case type::String:
+      return "String";
+    case type::Object:
+      return "Object";
+    default:
+      return "Unknown";
+  }
+}
+
+class rvalue;
+rvalue load(const char* data, size_t size);
+
+namespace detail {
+
+struct r_string : boost::less_than_comparable<r_string>,
+                  boost::less_than_comparable<r_string, std::string>,
+                  boost::equality_comparable<r_string>,
+                  boost::equality_comparable<r_string, std::string> {
+  r_string(){};
+  r_string(char* s, char* e) : s_(s), e_(e){};
+  ~r_string() {
+    if (owned_) delete[] s_;
+  }
+
+  r_string(const r_string& r) { *this = r; }
+
+  r_string(r_string&& r) { *this = r; }
+
+  r_string& operator=(r_string&& r) {
+    s_ = r.s_;
+    e_ = r.e_;
+    owned_ = r.owned_;
+    if (r.owned_) r.owned_ = 0;
+    return *this;
+  }
+
+  r_string& operator=(const r_string& r) {
+    s_ = r.s_;
+    e_ = r.e_;
+    owned_ = 0;
+    return *this;
+  }
+
+  operator std::string() const { return std::string(s_, e_); }
+
+  const char* begin() const { return s_; }
+  const char* end() const { return e_; }
+  size_t size() const { return end() - begin(); }
+
+  using iterator = const char*;
+  using const_iterator = const char*;
+
+  char* s_;
+  mutable char* e_;
+  uint8_t owned_{0};
+  friend std::ostream& operator<<(std::ostream& os, const r_string& s) {
+    os << (std::string)s;
+    return os;
+  }
+
+ private:
+  void force(char* s, uint32_t /*length*/) {
+    s_ = s;
+    owned_ = 1;
+  }
+  friend rvalue crow::json::load(const char* data, size_t size);
+};
+
+inline bool operator<(const r_string& l, const r_string& r) {
+  return boost::lexicographical_compare(l, r);
+}
+
+inline bool operator<(const r_string& l, const std::string& r) {
+  return boost::lexicographical_compare(l, r);
+}
+
+inline bool operator>(const r_string& l, const std::string& r) {
+  return boost::lexicographical_compare(r, l);
+}
+
+inline bool operator==(const r_string& l, const r_string& r) {
+  return boost::equals(l, r);
+}
+
+inline bool operator==(const r_string& l, const std::string& r) {
+  return boost::equals(l, r);
+}
+}
+
+class rvalue {
+  static const int cached_bit = 2;
+  static const int error_bit = 4;
+
+ public:
+  rvalue() noexcept : option_{error_bit} {}
+  rvalue(type t) noexcept : lsize_{}, lremain_{}, t_{t} {}
+  rvalue(type t, char* s, char* e) noexcept : start_{s}, end_{e}, t_{t} {}
+
+  rvalue(const rvalue& r)
+      : start_(r.start_),
+        end_(r.end_),
+        key_(r.key_),
+        t_(r.t_),
+        option_(r.option_) {
+    copy_l(r);
+  }
+
+  rvalue(rvalue&& r) noexcept { *this = std::move(r); }
+
+  rvalue& operator=(const rvalue& r) {
+    start_ = r.start_;
+    end_ = r.end_;
+    key_ = r.key_;
+    copy_l(r);
+    t_ = r.t_;
+    option_ = r.option_;
+    return *this;
+  }
+  rvalue& operator=(rvalue&& r) noexcept {
+    start_ = r.start_;
+    end_ = r.end_;
+    key_ = std::move(r.key_);
+    l_ = std::move(r.l_);
+    lsize_ = r.lsize_;
+    lremain_ = r.lremain_;
+    t_ = r.t_;
+    option_ = r.option_;
+    return *this;
+  }
+
+  explicit operator bool() const noexcept { return (option_ & error_bit) == 0; }
+
+  explicit operator int64_t() const { return i(); }
+
+  explicit operator uint64_t() const { return u(); }
+
+  explicit operator int() const { return (int)i(); }
+
+  type t() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (option_ & error_bit) {
+      throw std::runtime_error("invalid json object");
+    }
+#endif
+    return t_;
+  }
+
+  int64_t i() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    switch (t()) {
+      case type::Number:
+      case type::String:
+        return boost::lexical_cast<int64_t>(start_, end_ - start_);
+      default:
+        const std::string msg =
+            "expected number, got: " + std::string(get_type_str(t()));
+        throw std::runtime_error(msg);
+    }
+#endif
+    return boost::lexical_cast<int64_t>(start_, end_ - start_);
+  }
+
+  uint64_t u() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    switch (t()) {
+      case type::Number:
+      case type::String:
+        return boost::lexical_cast<uint64_t>(start_, end_ - start_);
+      default:
+        throw std::runtime_error(std::string("expected number, got: ") +
+                                 get_type_str(t()));
+    }
+#endif
+    return boost::lexical_cast<uint64_t>(start_, end_ - start_);
+  }
+
+  double d() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::Number) throw std::runtime_error("value is not number");
+#endif
+    return boost::lexical_cast<double>(start_, end_ - start_);
+  }
+
+  bool b() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::True && t() != type::False)
+      throw std::runtime_error("value is not boolean");
+#endif
+    return t() == type::True;
+  }
+
+  void unescape() const {
+    if (*(start_ - 1)) {
+      char* head = start_;
+      char* tail = start_;
+      while (head != end_) {
+        if (*head == '\\') {
+          switch (*++head) {
+            case '"':
+              *tail++ = '"';
+              break;
+            case '\\':
+              *tail++ = '\\';
+              break;
+            case '/':
+              *tail++ = '/';
+              break;
+            case 'b':
+              *tail++ = '\b';
+              break;
+            case 'f':
+              *tail++ = '\f';
+              break;
+            case 'n':
+              *tail++ = '\n';
+              break;
+            case 'r':
+              *tail++ = '\r';
+              break;
+            case 't':
+              *tail++ = '\t';
+              break;
+            case 'u': {
+              auto from_hex = [](char c) {
+                if (c >= 'a') return c - 'a' + 10;
+                if (c >= 'A') return c - 'A' + 10;
+                return c - '0';
+              };
+              unsigned int code = (from_hex(head[1]) << 12) +
+                                  (from_hex(head[2]) << 8) +
+                                  (from_hex(head[3]) << 4) + from_hex(head[4]);
+              if (code >= 0x800) {
+                *tail++ = 0xE0 | (code >> 12);
+                *tail++ = 0x80 | ((code >> 6) & 0x3F);
+                *tail++ = 0x80 | (code & 0x3F);
+              } else if (code >= 0x80) {
+                *tail++ = 0xC0 | (code >> 6);
+                *tail++ = 0x80 | (code & 0x3F);
+              } else {
+                *tail++ = code;
+              }
+              head += 4;
+            } break;
+          }
+        } else
+          *tail++ = *head;
+        head++;
+      }
+      end_ = tail;
+      *end_ = 0;
+      *(start_ - 1) = 0;
+    }
+  }
+
+  detail::r_string s() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::String) throw std::runtime_error("value is not string");
+#endif
+    unescape();
+    return detail::r_string{start_, end_};
+  }
+
+  bool has(const char* str) const { return has(std::string(str)); }
+
+  bool has(const std::string& str) const {
+    struct Pred {
+      bool operator()(const rvalue& l, const rvalue& r) const {
+        return l.key_ < r.key_;
+      };
+      bool operator()(const rvalue& l, const std::string& r) const {
+        return l.key_ < r;
+      };
+      bool operator()(const std::string& l, const rvalue& r) const {
+        return l < r.key_;
+      };
+    };
+    if (!is_cached()) {
+      std::sort(begin(), end(), Pred());
+      set_cached();
+    }
+    auto it = lower_bound(begin(), end(), str, Pred());
+    return it != end() && it->key_ == str;
+  }
+
+  int count(const std::string& str) { return has(str) ? 1 : 0; }
+
+  rvalue* begin() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::Object && t() != type::List)
+      throw std::runtime_error("value is not a container");
+#endif
+    return l_.get();
+  }
+  rvalue* end() const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::Object && t() != type::List)
+      throw std::runtime_error("value is not a container");
+#endif
+    return l_.get() + lsize_;
+  }
+
+  const detail::r_string& key() const { return key_; }
+
+  size_t size() const {
+    if (t() == type::String) return s().size();
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::Object && t() != type::List)
+      throw std::runtime_error("value is not a container");
+#endif
+    return lsize_;
+  }
+
+  const rvalue& operator[](int index) const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::List) throw std::runtime_error("value is not a list");
+    if (index >= (int)lsize_ || index < 0)
+      throw std::runtime_error("list out of bound");
+#endif
+    return l_[index];
+  }
+
+  const rvalue& operator[](size_t index) const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::List) throw std::runtime_error("value is not a list");
+    if (index >= lsize_) throw std::runtime_error("list out of bound");
+#endif
+    return l_[index];
+  }
+
+  const rvalue& operator[](const char* str) const {
+    return this->operator[](std::string(str));
+  }
+
+  const rvalue& operator[](const std::string& str) const {
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    if (t() != type::Object) throw std::runtime_error("value is not an object");
+#endif
+    struct Pred {
+      bool operator()(const rvalue& l, const rvalue& r) const {
+        return l.key_ < r.key_;
+      };
+      bool operator()(const rvalue& l, const std::string& r) const {
+        return l.key_ < r;
+      };
+      bool operator()(const std::string& l, const rvalue& r) const {
+        return l < r.key_;
+      };
+    };
+    if (!is_cached()) {
+      std::sort(begin(), end(), Pred());
+      set_cached();
+    }
+    auto it = lower_bound(begin(), end(), str, Pred());
+    if (it != end() && it->key_ == str) return *it;
+#ifndef CROW_JSON_NO_ERROR_CHECK
+    throw std::runtime_error("cannot find key");
+#else
+    static rvalue nullValue;
+    return nullValue;
+#endif
+  }
+
+  void set_error() { option_ |= error_bit; }
+
+  bool error() const { return (option_ & error_bit) != 0; }
+
+ private:
+  bool is_cached() const { return (option_ & cached_bit) != 0; }
+  void set_cached() const { option_ |= cached_bit; }
+  void copy_l(const rvalue& r) {
+    if (r.t() != type::Object && r.t() != type::List) return;
+    lsize_ = r.lsize_;
+    lremain_ = 0;
+    l_.reset(new rvalue[lsize_]);
+    std::copy(r.begin(), r.end(), begin());
+  }
+
+  void emplace_back(rvalue&& v) {
+    if (!lremain_) {
+      int new_size = lsize_ + lsize_;
+      if (new_size - lsize_ > 60000) new_size = lsize_ + 60000;
+      if (new_size < 4) new_size = 4;
+      rvalue* p = new rvalue[new_size];
+      rvalue* p2 = p;
+      for (auto& x : *this) *p2++ = std::move(x);
+      l_.reset(p);
+      lremain_ = new_size - lsize_;
+    }
+    l_[lsize_++] = std::move(v);
+    lremain_--;
+  }
+
+  mutable char* start_;
+  mutable char* end_;
+  detail::r_string key_;
+  std::unique_ptr<rvalue[]> l_;
+  uint32_t lsize_;
+  uint16_t lremain_;
+  type t_;
+  mutable uint8_t option_{0};
+
+  friend rvalue load_nocopy_internal(char* data, size_t size);
+  friend rvalue load(const char* data, size_t size);
+  friend std::ostream& operator<<(std::ostream& os, const rvalue& r) {
+    switch (r.t_) {
+      case type::Null:
+        os << "null";
+        break;
+      case type::False:
+        os << "false";
+        break;
+      case type::True:
+        os << "true";
+        break;
+      case type::Number:
+        os << r.d();
+        break;
+      case type::String:
+        os << '"' << r.s() << '"';
+        break;
+      case type::List: {
+        os << '[';
+        bool first = true;
+        for (auto& x : r) {
+          if (!first) os << ',';
+          first = false;
+          os << x;
+        }
+        os << ']';
+      } break;
+      case type::Object: {
+        os << '{';
+        bool first = true;
+        for (auto& x : r) {
+          if (!first) os << ',';
+          os << '"' << escape(x.key_) << "\":";
+          first = false;
+          os << x;
+        }
+        os << '}';
+      } break;
+    }
+    return os;
+  }
+};
+namespace detail {}
+
+inline bool operator==(const rvalue& l, const std::string& r) {
+  return l.s() == r;
+}
+
+inline bool operator==(const std::string& l, const rvalue& r) {
+  return l == r.s();
+}
+
+inline bool operator!=(const rvalue& l, const std::string& r) {
+  return l.s() != r;
+}
+
+inline bool operator!=(const std::string& l, const rvalue& r) {
+  return l != r.s();
+}
+
+inline bool operator==(const rvalue& l, double r) { return l.d() == r; }
+
+inline bool operator==(double l, const rvalue& r) { return l == r.d(); }
+
+inline bool operator!=(const rvalue& l, double r) { return l.d() != r; }
+
+inline bool operator!=(double l, const rvalue& r) { return l != r.d(); }
+
+inline rvalue load_nocopy_internal(char* data, size_t size) {
+  // static const char* escaped = "\"\\/\b\f\n\r\t";
+  struct Parser {
+    Parser(char* data, size_t /*size*/) : data(data) {}
+
+    bool consume(char c) {
+      if (crow_json_unlikely(*data != c)) return false;
+      data++;
+      return true;
+    }
+
+    void ws_skip() {
+      while (*data == ' ' || *data == '\t' || *data == '\r' || *data == '\n')
+        ++data;
+    };
+
+    rvalue decode_string() {
+      if (crow_json_unlikely(!consume('"'))) return {};
+      char* start = data;
+      uint8_t has_escaping = 0;
+      while (1) {
+        if (crow_json_likely(*data != '"' && *data != '\\' && *data != '\0')) {
+          data++;
+        } else if (*data == '"') {
+          *data = 0;
+          *(start - 1) = has_escaping;
+          data++;
+          return {type::String, start, data - 1};
+        } else if (*data == '\\') {
+          has_escaping = 1;
+          data++;
+          switch (*data) {
+            case 'u': {
+              auto check = [](char c) {
+                return ('0' <= c && c <= '9') || ('a' <= c && c <= 'f') ||
+                       ('A' <= c && c <= 'F');
+              };
+              if (!(check(*(data + 1)) && check(*(data + 2)) &&
+                    check(*(data + 3)) && check(*(data + 4))))
+                return {};
+            }
+              data += 5;
+              break;
+            case '"':
+            case '\\':
+            case '/':
+            case 'b':
+            case 'f':
+            case 'n':
+            case 'r':
+            case 't':
+              data++;
+              break;
+            default:
+              return {};
+          }
+        } else
+          return {};
+      }
+      return {};
+    }
+
+    rvalue decode_list() {
+      rvalue ret(type::List);
+      if (crow_json_unlikely(!consume('['))) {
+        ret.set_error();
+        return ret;
+      }
+      ws_skip();
+      if (crow_json_unlikely(*data == ']')) {
+        data++;
+        return ret;
+      }
+
+      while (1) {
+        auto v = decode_value();
+        if (crow_json_unlikely(!v)) {
+          ret.set_error();
+          break;
+        }
+        ws_skip();
+        ret.emplace_back(std::move(v));
+        if (*data == ']') {
+          data++;
+          break;
+        }
+        if (crow_json_unlikely(!consume(','))) {
+          ret.set_error();
+          break;
+        }
+        ws_skip();
+      }
+      return ret;
+    }
+
+    rvalue decode_number() {
+      char* start = data;
+
+      enum NumberParsingState {
+        Minus,
+        AfterMinus,
+        ZeroFirst,
+        Digits,
+        DigitsAfterPoints,
+        E,
+        DigitsAfterE,
+        Invalid,
+      } state{Minus};
+      while (crow_json_likely(state != Invalid)) {
+        switch (*data) {
+          case '0':
+            state = (NumberParsingState) "\2\2\7\3\4\6\6"[state];
+            /*if (state == NumberParsingState::Minus || state ==
+            NumberParsingState::AfterMinus)
+            {
+                state = NumberParsingState::ZeroFirst;
+            }
+            else if (state == NumberParsingState::Digits ||
+                state == NumberParsingState::DigitsAfterE ||
+                state == NumberParsingState::DigitsAfterPoints)
+            {
+                // ok; pass
+            }
+            else if (state == NumberParsingState::E)
+            {
+                state = NumberParsingState::DigitsAfterE;
+            }
+            else
+                return {};*/
+            break;
+          case '1':
+          case '2':
+          case '3':
+          case '4':
+          case '5':
+          case '6':
+          case '7':
+          case '8':
+          case '9':
+            state = (NumberParsingState) "\3\3\7\3\4\6\6"[state];
+            while (*(data + 1) >= '0' && *(data + 1) <= '9') data++;
+            /*if (state == NumberParsingState::Minus || state ==
+            NumberParsingState::AfterMinus)
+            {
+                state = NumberParsingState::Digits;
+            }
+            else if (state == NumberParsingState::Digits ||
+                state == NumberParsingState::DigitsAfterE ||
+                state == NumberParsingState::DigitsAfterPoints)
+            {
+                // ok; pass
+            }
+            else if (state == NumberParsingState::E)
+            {
+                state = NumberParsingState::DigitsAfterE;
+            }
+            else
+                return {};*/
+            break;
+          case '.':
+            state = (NumberParsingState) "\7\7\4\4\7\7\7"[state];
+            /*
+            if (state == NumberParsingState::Digits || state ==
+            NumberParsingState::ZeroFirst)
+            {
+                state = NumberParsingState::DigitsAfterPoints;
+            }
+            else
+                return {};
+            */
+            break;
+          case '-':
+            state = (NumberParsingState) "\1\7\7\7\7\6\7"[state];
+            /*if (state == NumberParsingState::Minus)
+            {
+                state = NumberParsingState::AfterMinus;
+            }
+            else if (state == NumberParsingState::E)
+            {
+                state = NumberParsingState::DigitsAfterE;
+            }
+            else
+                return {};*/
+            break;
+          case '+':
+            state = (NumberParsingState) "\7\7\7\7\7\6\7"[state];
+            /*if (state == NumberParsingState::E)
+            {
+                state = NumberParsingState::DigitsAfterE;
+            }
+            else
+                return {};*/
+            break;
+          case 'e':
+          case 'E':
+            state = (NumberParsingState) "\7\7\7\5\5\7\7"[state];
+            /*if (state == NumberParsingState::Digits ||
+                state == NumberParsingState::DigitsAfterPoints)
+            {
+                state = NumberParsingState::E;
+            }
+            else
+                return {};*/
+            break;
+          default:
+            if (crow_json_likely(state == NumberParsingState::ZeroFirst ||
+                                 state == NumberParsingState::Digits ||
+                                 state ==
+                                     NumberParsingState::DigitsAfterPoints ||
+                                 state == NumberParsingState::DigitsAfterE))
+              return {type::Number, start, data};
+            else
+              return {};
+        }
+        data++;
+      }
+
+      return {};
+    }
+
+    rvalue decode_value() {
+      switch (*data) {
+        case '[':
+          return decode_list();
+        case '{':
+          return decode_object();
+        case '"':
+          return decode_string();
+        case 't':
+          if (  // e-data >= 4 &&
+              data[1] == 'r' && data[2] == 'u' && data[3] == 'e') {
+            data += 4;
+            return {type::True};
+          } else
+            return {};
+        case 'f':
+          if (  // e-data >= 5 &&
+              data[1] == 'a' && data[2] == 'l' && data[3] == 's' &&
+              data[4] == 'e') {
+            data += 5;
+            return {type::False};
+          } else
+            return {};
+        case 'n':
+          if (  // e-data >= 4 &&
+              data[1] == 'u' && data[2] == 'l' && data[3] == 'l') {
+            data += 4;
+            return {type::Null};
+          } else
+            return {};
+        // case '1': case '2': case '3':
+        // case '4': case '5': case '6':
+        // case '7': case '8': case '9':
+        // case '0': case '-':
+        default:
+          return decode_number();
+      }
+      return {};
+    }
+
+    rvalue decode_object() {
+      rvalue ret(type::Object);
+      if (crow_json_unlikely(!consume('{'))) {
+        ret.set_error();
+        return ret;
+      }
+
+      ws_skip();
+
+      if (crow_json_unlikely(*data == '}')) {
+        data++;
+        return ret;
+      }
+
+      while (1) {
+        auto t = decode_string();
+        if (crow_json_unlikely(!t)) {
+          ret.set_error();
+          break;
+        }
+
+        ws_skip();
+        if (crow_json_unlikely(!consume(':'))) {
+          ret.set_error();
+          break;
+        }
+
+        // TODO caching key to speed up (flyweight?)
+        auto key = t.s();
+
+        ws_skip();
+        auto v = decode_value();
+        if (crow_json_unlikely(!v)) {
+          ret.set_error();
+          break;
+        }
+        ws_skip();
+
+        v.key_ = std::move(key);
+        ret.emplace_back(std::move(v));
+        if (crow_json_unlikely(*data == '}')) {
+          data++;
+          break;
+        }
+        if (crow_json_unlikely(!consume(','))) {
+          ret.set_error();
+          break;
+        }
+        ws_skip();
+      }
+      return ret;
+    }
+
+    rvalue parse() {
+      ws_skip();
+      auto ret = decode_value();  // or decode object?
+      ws_skip();
+      if (ret && *data != '\0') ret.set_error();
+      return ret;
+    }
+
+    char* data;
+  };
+  return Parser(data, size).parse();
+}
+inline rvalue load(const char* data, size_t size) {
+  char* s = new char[size + 1];
+  memcpy(s, data, size);
+  s[size] = 0;
+  auto ret = load_nocopy_internal(s, size);
+  if (ret)
+    ret.key_.force(s, size);
+  else
+    delete[] s;
+  return ret;
+}
+
+inline rvalue load(const char* data) { return load(data, strlen(data)); }
+
+inline rvalue load(const std::string& str) {
+  return load(str.data(), str.size());
+}
+
+class wvalue {
+  friend class crow::mustache::template_t;
+
+ public:
+  type t() const { return t_; }
+
+ private:
+  type t_{type::Null};
+  double d{};
+  std::string s;
+  std::unique_ptr<std::vector<wvalue>> l;
+  std::unique_ptr<std::unordered_map<std::string, wvalue>> o;
+
+ public:
+  wvalue() {}
+
+  wvalue(const rvalue& r) {
+    t_ = r.t();
+    switch (r.t()) {
+      case type::Null:
+      case type::False:
+      case type::True:
+        return;
+      case type::Number:
+        d = r.d();
+        return;
+      case type::String:
+        s = r.s();
+        return;
+      case type::List:
+        l = std::unique_ptr<std::vector<wvalue>>(new std::vector<wvalue>{});
+        l->reserve(r.size());
+        for (auto it = r.begin(); it != r.end(); ++it) l->emplace_back(*it);
+        return;
+      case type::Object:
+        o = std::unique_ptr<std::unordered_map<std::string, wvalue>>(
+            new std::unordered_map<std::string, wvalue>{});
+        for (auto it = r.begin(); it != r.end(); ++it)
+          o->emplace(it->key(), *it);
+        return;
+    }
+  }
+
+  wvalue(wvalue&& r) { *this = std::move(r); }
+
+  wvalue& operator=(wvalue&& r) {
+    t_ = r.t_;
+    d = r.d;
+    s = std::move(r.s);
+    l = std::move(r.l);
+    o = std::move(r.o);
+    return *this;
+  }
+
+  void clear() {
+    t_ = type::Null;
+    l.reset();
+    o.reset();
+  }
+
+  void reset() {
+    t_ = type::Null;
+    l.reset();
+    o.reset();
+  }
+
+  wvalue& operator=(std::nullptr_t) {
+    reset();
+    return *this;
+  }
+  wvalue& operator=(bool value) {
+    reset();
+    if (value)
+      t_ = type::True;
+    else
+      t_ = type::False;
+    return *this;
+  }
+
+  wvalue& operator=(double value) {
+    reset();
+    t_ = type::Number;
+    d = value;
+    return *this;
+  }
+
+  wvalue& operator=(unsigned short value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(short value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(long long value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(long value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(int value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(unsigned long long value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(unsigned long value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(unsigned int value) {
+    reset();
+    t_ = type::Number;
+    d = (double)value;
+    return *this;
+  }
+
+  wvalue& operator=(const char* str) {
+    reset();
+    t_ = type::String;
+    s = str;
+    return *this;
+  }
+
+  wvalue& operator=(const std::string& str) {
+    reset();
+    t_ = type::String;
+    s = str;
+    return *this;
+  }
+
+  template <typename T>
+  wvalue& operator=(const std::vector<T>& v) {
+    if (t_ != type::List) reset();
+    t_ = type::List;
+    if (!l) l = std::unique_ptr<std::vector<wvalue>>(new std::vector<wvalue>{});
+    l->clear();
+    l->resize(v.size());
+    size_t idx = 0;
+    for (auto& x : v) {
+      (*l)[idx++] = x;
+    }
+    return *this;
+  }
+
+  wvalue& operator[](unsigned index) {
+    if (t_ != type::List) reset();
+    t_ = type::List;
+    if (!l) l = std::unique_ptr<std::vector<wvalue>>(new std::vector<wvalue>{});
+    if (l->size() < index + 1) l->resize(index + 1);
+    return (*l)[index];
+  }
+
+  int count(const std::string& str) {
+    if (t_ != type::Object) return 0;
+    if (!o) return 0;
+    return o->count(str);
+  }
+
+  wvalue& operator[](const std::string& str) {
+    if (t_ != type::Object) reset();
+    t_ = type::Object;
+    if (!o)
+      o = std::unique_ptr<std::unordered_map<std::string, wvalue>>(
+          new std::unordered_map<std::string, wvalue>{});
+    return (*o)[str];
+  }
+
+  size_t estimate_length() const {
+    switch (t_) {
+      case type::Null:
+        return 4;
+      case type::False:
+        return 5;
+      case type::True:
+        return 4;
+      case type::Number:
+        return 30;
+      case type::String:
+        return 2 + s.size() + s.size() / 2;
+      case type::List: {
+        size_t sum{};
+        if (l) {
+          for (auto& x : *l) {
+            sum += 1;
+            sum += x.estimate_length();
+          }
+        }
+        return sum + 2;
+      }
+      case type::Object: {
+        size_t sum{};
+        if (o) {
+          for (auto& kv : *o) {
+            sum += 2;
+            sum += 2 + kv.first.size() + kv.first.size() / 2;
+            sum += kv.second.estimate_length();
+          }
+        }
+        return sum + 2;
+      }
+    }
+    return 1;
+  }
+
+  friend void dump_internal(const wvalue& v, std::string& out);
+  friend std::string dump(const wvalue& v);
+};
+
+inline void dump_string(const std::string& str, std::string& out) {
+  out.push_back('"');
+  escape(str, out);
+  out.push_back('"');
+}
+inline void dump_internal(const wvalue& v, std::string& out) {
+  switch (v.t_) {
+    case type::Null:
+      out += "null";
+      break;
+    case type::False:
+      out += "false";
+      break;
+    case type::True:
+      out += "true";
+      break;
+    case type::Number: {
+      char outbuf[128];
+      sprintf(outbuf, "%g", v.d);
+      out += outbuf;
+    } break;
+    case type::String:
+      dump_string(v.s, out);
+      break;
+    case type::List: {
+      out.push_back('[');
+      if (v.l) {
+        bool first = true;
+        for (auto& x : *v.l) {
+          if (!first) {
+            out.push_back(',');
+          }
+          first = false;
+          dump_internal(x, out);
+        }
+      }
+      out.push_back(']');
+    } break;
+    case type::Object: {
+      out.push_back('{');
+      if (v.o) {
+        bool first = true;
+        for (auto& kv : *v.o) {
+          if (!first) {
+            out.push_back(',');
+          }
+          first = false;
+          dump_string(kv.first, out);
+          out.push_back(':');
+          dump_internal(kv.second, out);
+        }
+      }
+      out.push_back('}');
+    } break;
+  }
+}
+
+inline std::string dump(const wvalue& v) {
+  std::string ret;
+  ret.reserve(v.estimate_length());
+  dump_internal(v, ret);
+  return ret;
+}
+
+// std::vector<boost::asio::const_buffer> dump_ref(wvalue& v)
+//{
+//}
+}
+}
+
+#undef crow_json_likely
+#undef crow_json_unlikely
diff --git a/crow/include/crow/logging.h b/crow/include/crow/logging.h
new file mode 100644
index 0000000..bfdedb9
--- /dev/null
+++ b/crow/include/crow/logging.h
@@ -0,0 +1,3 @@
+#pragma once
+
+#include <crow/g3_logger.hpp>
\ No newline at end of file
diff --git a/crow/include/crow/middleware.h b/crow/include/crow/middleware.h
new file mode 100644
index 0000000..342f128
--- /dev/null
+++ b/crow/include/crow/middleware.h
@@ -0,0 +1,151 @@
+#pragma once
+#include <boost/algorithm/string/trim.hpp>
+#include "crow/http_request.h"
+#include "crow/http_response.h"
+
+namespace crow {
+// Any middleware requires following 3 members:
+
+// struct context;
+//      storing data for the middleware; can be read from another middleware or
+//      handlers
+
+// before_handle
+//      called before handling the request.
+//      if res.end() is called, the operation is halted.
+//      (still call after_handle of this middleware)
+//      2 signatures:
+//      void before_handle(request& req, response& res, context& ctx)
+//          if you only need to access this middlewares context.
+//      template <typename AllContext>
+//      void before_handle(request& req, response& res, context& ctx,
+//      AllContext& all_ctx)
+//          you can access another middlewares' context by calling
+//          `all_ctx.template get<MW>()'
+//          ctx == all_ctx.template get<CurrentMiddleware>()
+
+// after_handle
+//      called after handling the request.
+//      void after_handle(request& req, response& res, context& ctx)
+//      template <typename AllContext>
+//      void after_handle(request& req, response& res, context& ctx, AllContext&
+//      all_ctx)
+
+struct CookieParser {
+  struct context {
+    std::unordered_map<std::string, std::string> jar;
+    std::unordered_map<std::string, std::string> cookies_to_add;
+
+    std::string get_cookie(const std::string& key) {
+      if (jar.count(key)) return jar[key];
+      return {};
+    }
+
+    void set_cookie(const std::string& key, const std::string& value) {
+      cookies_to_add.emplace(key, value);
+    }
+  };
+
+  void before_handle(request& req, response& res, context& ctx) {
+    int count = req.headers.count("Cookie");
+    if (!count) return;
+    if (count > 1) {
+      res.code = 400;
+      res.end();
+      return;
+    }
+    std::string cookies = req.get_header_value("Cookie");
+    size_t pos = 0;
+    while (pos < cookies.size()) {
+      size_t pos_equal = cookies.find('=', pos);
+      if (pos_equal == cookies.npos) break;
+      std::string name = cookies.substr(pos, pos_equal - pos);
+      boost::trim(name);
+      pos = pos_equal + 1;
+      while (pos < cookies.size() && cookies[pos] == ' ') pos++;
+      if (pos == cookies.size()) break;
+
+      std::string value;
+
+      if (cookies[pos] == '"') {
+        int dquote_meet_count = 0;
+        pos++;
+        size_t pos_dquote = pos - 1;
+        do {
+          pos_dquote = cookies.find('"', pos_dquote + 1);
+          dquote_meet_count++;
+        } while (pos_dquote < cookies.size() &&
+                 cookies[pos_dquote - 1] == '\\');
+        if (pos_dquote == cookies.npos) break;
+
+        if (dquote_meet_count == 1)
+          value = cookies.substr(pos, pos_dquote - pos);
+        else {
+          value.clear();
+          value.reserve(pos_dquote - pos);
+          for (size_t p = pos; p < pos_dquote; p++) {
+            // FIXME minimal escaping
+            if (cookies[p] == '\\' && p + 1 < pos_dquote) {
+              p++;
+              if (cookies[p] == '\\' || cookies[p] == '"')
+                value += cookies[p];
+              else {
+                value += '\\';
+                value += cookies[p];
+              }
+            } else
+              value += cookies[p];
+          }
+        }
+
+        ctx.jar.emplace(std::move(name), std::move(value));
+        pos = cookies.find(";", pos_dquote + 1);
+        if (pos == cookies.npos) break;
+        pos++;
+        while (pos < cookies.size() && cookies[pos] == ' ') pos++;
+        if (pos == cookies.size()) break;
+      } else {
+        size_t pos_semicolon = cookies.find(';', pos);
+        value = cookies.substr(pos, pos_semicolon - pos);
+        boost::trim(value);
+        ctx.jar.emplace(std::move(name), std::move(value));
+        pos = pos_semicolon;
+        if (pos == cookies.npos) break;
+        pos++;
+        while (pos < cookies.size() && cookies[pos] == ' ') pos++;
+        if (pos == cookies.size()) break;
+      }
+    }
+  }
+
+  void after_handle(request& /*req*/, response& res, context& ctx) {
+    for (auto& cookie : ctx.cookies_to_add) {
+      res.add_header("Set-Cookie", cookie.first + "=" + cookie.second);
+    }
+  }
+};
+
+/*
+App<CookieParser, AnotherJarMW> app;
+A B C
+A::context
+    int aa;
+
+ctx1 : public A::context
+ctx2 : public ctx1, public B::context
+ctx3 : public ctx2, public C::context
+
+C depends on A
+
+C::handle
+    context.aaa
+
+App::context : private CookieParser::contetx, ...
+{
+    jar
+
+}
+
+SimpleApp
+*/
+}
diff --git a/crow/include/crow/middleware_context.h b/crow/include/crow/middleware_context.h
new file mode 100644
index 0000000..80f7fd8
--- /dev/null
+++ b/crow/include/crow/middleware_context.h
@@ -0,0 +1,63 @@
+#pragma once
+
+#include "crow/http_request.h"
+#include "crow/http_response.h"
+#include "crow/utility.h"
+
+namespace crow {
+namespace detail {
+template <typename... Middlewares>
+struct partial_context
+    : public black_magic::pop_back<Middlewares...>::template rebind<
+          partial_context>,
+      public black_magic::last_element_type<Middlewares...>::type::context {
+  using parent_context = typename black_magic::pop_back<
+      Middlewares...>::template rebind<::crow::detail::partial_context>;
+  template <int N>
+  using partial = typename std::conditional<
+      N == sizeof...(Middlewares)-1, partial_context,
+      typename parent_context::template partial<N>>::type;
+
+  template <typename T>
+  typename T::context& get() {
+    return static_cast<typename T::context&>(*this);
+  }
+};
+
+template <>
+struct partial_context<> {
+  template <int>
+  using partial = partial_context;
+};
+
+template <int N, typename Context, typename Container, typename CurrentMW,
+          typename... Middlewares>
+bool middleware_call_helper(Container& middlewares, request& req, response& res,
+                            Context& ctx);
+
+template <typename... Middlewares>
+struct context : private partial_context<Middlewares...>
+// struct context : private Middlewares::context... // simple but less type-safe
+{
+  template <int N, typename Context, typename Container>
+  friend typename std::enable_if<(N == 0)>::type after_handlers_call_helper(
+      Container& middlewares, Context& ctx, request& req, response& res);
+  template <int N, typename Context, typename Container>
+  friend typename std::enable_if<(N > 0)>::type after_handlers_call_helper(
+      Container& middlewares, Context& ctx, request& req, response& res);
+
+  template <int N, typename Context, typename Container, typename CurrentMW,
+            typename... Middlewares2>
+  friend bool middleware_call_helper(Container& middlewares, request& req,
+                                     response& res, Context& ctx);
+
+  template <typename T>
+  typename T::context& get() {
+    return static_cast<typename T::context&>(*this);
+  }
+
+  template <int N>
+  using partial = typename partial_context<Middlewares...>::template partial<N>;
+};
+}
+}
diff --git a/crow/include/crow/mustache.h b/crow/include/crow/mustache.h
new file mode 100644
index 0000000..dbac6d6
--- /dev/null
+++ b/crow/include/crow/mustache.h
@@ -0,0 +1,511 @@
+#pragma once
+#include <fstream>
+#include <functional>
+#include <iterator>
+#include <string>
+#include <vector>
+#include "crow/json.h"
+namespace crow {
+namespace mustache {
+using context = json::wvalue;
+
+template_t load(const std::string& filename);
+
+class invalid_template_exception : public std::exception {
+ public:
+  invalid_template_exception(const std::string& msg)
+      : msg("crow::mustache error: " + msg) {}
+  virtual const char* what() const throw() { return msg.c_str(); }
+  std::string msg;
+};
+
+enum class ActionType {
+  Ignore,
+  Tag,
+  UnescapeTag,
+  OpenBlock,
+  CloseBlock,
+  ElseBlock,
+  Partial,
+};
+
+struct Action {
+  int start;
+  int end;
+  int pos;
+  ActionType t;
+  Action(ActionType t, int start, int end, int pos = 0)
+      : start(start), end(end), pos(pos), t(t) {}
+};
+
+class template_t {
+ public:
+  template_t(std::string body) : body_(std::move(body)) {
+    // {{ {{# {{/ {{^ {{! {{> {{=
+    parse();
+  }
+
+ private:
+  std::string tag_name(const Action& action) {
+    return body_.substr(action.start, action.end - action.start);
+  }
+  auto find_context(const std::string& name, const std::vector<context*>& stack)
+      -> std::pair<bool, context&> {
+    if (name == ".") {
+      return {true, *stack.back()};
+    }
+    int dotPosition = name.find(".");
+    if (dotPosition == (int)name.npos) {
+      for (auto it = stack.rbegin(); it != stack.rend(); ++it) {
+        if ((*it)->t() == json::type::Object) {
+          if ((*it)->count(name)) return {true, (**it)[name]};
+        }
+      }
+    } else {
+      std::vector<int> dotPositions;
+      dotPositions.push_back(-1);
+      while (dotPosition != (int)name.npos) {
+        dotPositions.push_back(dotPosition);
+        dotPosition = name.find(".", dotPosition + 1);
+      }
+      dotPositions.push_back(name.size());
+      std::vector<std::string> names;
+      names.reserve(dotPositions.size() - 1);
+      for (int i = 1; i < (int)dotPositions.size(); i++)
+        names.emplace_back(
+            name.substr(dotPositions[i - 1] + 1,
+                        dotPositions[i] - dotPositions[i - 1] - 1));
+
+      for (auto it = stack.rbegin(); it != stack.rend(); ++it) {
+        context* view = *it;
+        bool found = true;
+        for (auto jt = names.begin(); jt != names.end(); ++jt) {
+          if (view->t() == json::type::Object && view->count(*jt)) {
+            view = &(*view)[*jt];
+          } else {
+            found = false;
+            break;
+          }
+        }
+        if (found) return {true, *view};
+      }
+    }
+
+    static json::wvalue empty_str;
+    empty_str = "";
+    return {false, empty_str};
+  }
+
+  void escape(const std::string& in, std::string& out) {
+    out.reserve(out.size() + in.size());
+    for (auto it = in.begin(); it != in.end(); ++it) {
+      switch (*it) {
+        case '&':
+          out += "&amp;";
+          break;
+        case '<':
+          out += "&lt;";
+          break;
+        case '>':
+          out += "&gt;";
+          break;
+        case '"':
+          out += "&quot;";
+          break;
+        case '\'':
+          out += "&#39;";
+          break;
+        case '/':
+          out += "&#x2F;";
+          break;
+        default:
+          out += *it;
+          break;
+      }
+    }
+  }
+
+  void render_internal(int actionBegin, int actionEnd,
+                       std::vector<context*>& stack, std::string& out,
+                       int indent) {
+    int current = actionBegin;
+
+    if (indent) out.insert(out.size(), indent, ' ');
+
+    while (current < actionEnd) {
+      auto& fragment = fragments_[current];
+      auto& action = actions_[current];
+      render_fragment(fragment, indent, out);
+      switch (action.t) {
+        case ActionType::Ignore:
+          // do nothing
+          break;
+        case ActionType::Partial: {
+          std::string partial_name = tag_name(action);
+          auto partial_templ = load(partial_name);
+          int partial_indent = action.pos;
+          partial_templ.render_internal(
+              0, partial_templ.fragments_.size() - 1, stack, out,
+              partial_indent ? indent + partial_indent : 0);
+        } break;
+        case ActionType::UnescapeTag:
+        case ActionType::Tag: {
+          auto optional_ctx = find_context(tag_name(action), stack);
+          auto& ctx = optional_ctx.second;
+          switch (ctx.t()) {
+            case json::type::Number:
+              out += json::dump(ctx);
+              break;
+            case json::type::String:
+              if (action.t == ActionType::Tag)
+                escape(ctx.s, out);
+              else
+                out += ctx.s;
+              break;
+            default:
+              throw std::runtime_error(
+                  "not implemented tag type" +
+                  boost::lexical_cast<std::string>((int)ctx.t()));
+          }
+        } break;
+        case ActionType::ElseBlock: {
+          static context nullContext;
+          auto optional_ctx = find_context(tag_name(action), stack);
+          if (!optional_ctx.first) {
+            stack.emplace_back(&nullContext);
+            break;
+          }
+
+          auto& ctx = optional_ctx.second;
+          switch (ctx.t()) {
+            case json::type::List:
+              if (ctx.l && !ctx.l->empty())
+                current = action.pos;
+              else
+                stack.emplace_back(&nullContext);
+              break;
+            case json::type::False:
+            case json::type::Null:
+              stack.emplace_back(&nullContext);
+              break;
+            default:
+              current = action.pos;
+              break;
+          }
+          break;
+        }
+        case ActionType::OpenBlock: {
+          auto optional_ctx = find_context(tag_name(action), stack);
+          if (!optional_ctx.first) {
+            current = action.pos;
+            break;
+          }
+
+          auto& ctx = optional_ctx.second;
+          switch (ctx.t()) {
+            case json::type::List:
+              if (ctx.l)
+                for (auto it = ctx.l->begin(); it != ctx.l->end(); ++it) {
+                  stack.push_back(&*it);
+                  render_internal(current + 1, action.pos, stack, out, indent);
+                  stack.pop_back();
+                }
+              current = action.pos;
+              break;
+            case json::type::Number:
+            case json::type::String:
+            case json::type::Object:
+            case json::type::True:
+              stack.push_back(&ctx);
+              break;
+            case json::type::False:
+            case json::type::Null:
+              current = action.pos;
+              break;
+            default:
+              throw std::runtime_error(
+                  "{{#: not implemented context type: " +
+                  boost::lexical_cast<std::string>((int)ctx.t()));
+              break;
+          }
+          break;
+        }
+        case ActionType::CloseBlock:
+          stack.pop_back();
+          break;
+        default:
+          throw std::runtime_error(
+              "not implemented " +
+              boost::lexical_cast<std::string>((int)action.t));
+      }
+      current++;
+    }
+    auto& fragment = fragments_[actionEnd];
+    render_fragment(fragment, indent, out);
+  }
+  void render_fragment(const std::pair<int, int> fragment, int indent,
+                       std::string& out) {
+    if (indent) {
+      for (int i = fragment.first; i < fragment.second; i++) {
+        out += body_[i];
+        if (body_[i] == '\n' && i + 1 != (int)body_.size())
+          out.insert(out.size(), indent, ' ');
+      }
+    } else
+      out.insert(out.size(), body_, fragment.first,
+                 fragment.second - fragment.first);
+  }
+
+ public:
+  std::string render() {
+    context empty_ctx;
+    std::vector<context*> stack;
+    stack.emplace_back(&empty_ctx);
+
+    std::string ret;
+    render_internal(0, fragments_.size() - 1, stack, ret, 0);
+    return ret;
+  }
+  std::string render(context& ctx) {
+    std::vector<context*> stack;
+    stack.emplace_back(&ctx);
+
+    std::string ret;
+    render_internal(0, fragments_.size() - 1, stack, ret, 0);
+    return ret;
+  }
+
+ private:
+  void parse() {
+    std::string tag_open = "{{";
+    std::string tag_close = "}}";
+
+    std::vector<int> blockPositions;
+
+    size_t current = 0;
+    while (1) {
+      size_t idx = body_.find(tag_open, current);
+      if (idx == body_.npos) {
+        fragments_.emplace_back(current, body_.size());
+        actions_.emplace_back(ActionType::Ignore, 0, 0);
+        break;
+      }
+      fragments_.emplace_back(current, idx);
+
+      idx += tag_open.size();
+      size_t endIdx = body_.find(tag_close, idx);
+      if (endIdx == idx) {
+        throw invalid_template_exception("empty tag is not allowed");
+      }
+      if (endIdx == body_.npos) {
+        // error, no matching tag
+        throw invalid_template_exception("not matched opening tag");
+      }
+      current = endIdx + tag_close.size();
+      switch (body_[idx]) {
+        case '#':
+          idx++;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          blockPositions.emplace_back(actions_.size());
+          actions_.emplace_back(ActionType::OpenBlock, idx, endIdx);
+          break;
+        case '/':
+          idx++;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          {
+            auto& matched = actions_[blockPositions.back()];
+            if (body_.compare(idx, endIdx - idx, body_, matched.start,
+                              matched.end - matched.start) != 0) {
+              throw invalid_template_exception(
+                  "not matched {{# {{/ pair: " +
+                  body_.substr(matched.start, matched.end - matched.start) +
+                  ", " + body_.substr(idx, endIdx - idx));
+            }
+            matched.pos = actions_.size();
+          }
+          actions_.emplace_back(ActionType::CloseBlock, idx, endIdx,
+                                blockPositions.back());
+          blockPositions.pop_back();
+          break;
+        case '^':
+          idx++;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          blockPositions.emplace_back(actions_.size());
+          actions_.emplace_back(ActionType::ElseBlock, idx, endIdx);
+          break;
+        case '!':
+          // do nothing action
+          actions_.emplace_back(ActionType::Ignore, idx + 1, endIdx);
+          break;
+        case '>':  // partial
+          idx++;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          actions_.emplace_back(ActionType::Partial, idx, endIdx);
+          break;
+        case '{':
+          if (tag_open != "{{" || tag_close != "}}")
+            throw invalid_template_exception(
+                "cannot use triple mustache when delimiter changed");
+
+          idx++;
+          if (body_[endIdx + 2] != '}') {
+            throw invalid_template_exception("{{{: }}} not matched");
+          }
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          actions_.emplace_back(ActionType::UnescapeTag, idx, endIdx);
+          current++;
+          break;
+        case '&':
+          idx++;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          actions_.emplace_back(ActionType::UnescapeTag, idx, endIdx);
+          break;
+        case '=':
+          // tag itself is no-op
+          idx++;
+          actions_.emplace_back(ActionType::Ignore, idx, endIdx);
+          endIdx--;
+          if (body_[endIdx] != '=')
+            throw invalid_template_exception("{{=: not matching = tag: " +
+                                             body_.substr(idx, endIdx - idx));
+          endIdx--;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx] == ' ') endIdx--;
+          endIdx++;
+          {
+            bool succeeded = false;
+            for (size_t i = idx; i < endIdx; i++) {
+              if (body_[i] == ' ') {
+                tag_open = body_.substr(idx, i - idx);
+                while (body_[i] == ' ') i++;
+                tag_close = body_.substr(i, endIdx - i);
+                if (tag_open.empty())
+                  throw invalid_template_exception("{{=: empty open tag");
+                if (tag_close.empty())
+                  throw invalid_template_exception("{{=: empty close tag");
+
+                if (tag_close.find(" ") != tag_close.npos)
+                  throw invalid_template_exception(
+                      "{{=: invalid open/close tag: " + tag_open + " " +
+                      tag_close);
+                succeeded = true;
+                break;
+              }
+            }
+            if (!succeeded)
+              throw invalid_template_exception(
+                  "{{=: cannot find space between new open/close tags");
+          }
+          break;
+        default:
+          // normal tag case;
+          while (body_[idx] == ' ') idx++;
+          while (body_[endIdx - 1] == ' ') endIdx--;
+          actions_.emplace_back(ActionType::Tag, idx, endIdx);
+          break;
+      }
+    }
+
+    // removing standalones
+    for (int i = actions_.size() - 2; i >= 0; i--) {
+      if (actions_[i].t == ActionType::Tag ||
+          actions_[i].t == ActionType::UnescapeTag)
+        continue;
+      auto& fragment_before = fragments_[i];
+      auto& fragment_after = fragments_[i + 1];
+      bool is_last_action = i == (int)actions_.size() - 2;
+      bool all_space_before = true;
+      int j, k;
+      for (j = fragment_before.second - 1; j >= fragment_before.first; j--) {
+        if (body_[j] != ' ') {
+          all_space_before = false;
+          break;
+        }
+      }
+      if (all_space_before && i > 0) continue;
+      if (!all_space_before && body_[j] != '\n') continue;
+      bool all_space_after = true;
+      for (k = fragment_after.first;
+           k < (int)body_.size() && k < fragment_after.second; k++) {
+        if (body_[k] != ' ') {
+          all_space_after = false;
+          break;
+        }
+      }
+      if (all_space_after && !is_last_action) continue;
+      if (!all_space_after &&
+          !(body_[k] == '\n' ||
+            (body_[k] == '\r' && k + 1 < (int)body_.size() &&
+             body_[k + 1] == '\n')))
+        continue;
+      if (actions_[i].t == ActionType::Partial) {
+        actions_[i].pos = fragment_before.second - j - 1;
+      }
+      fragment_before.second = j + 1;
+      if (!all_space_after) {
+        if (body_[k] == '\n')
+          k++;
+        else
+          k += 2;
+        fragment_after.first = k;
+      }
+    }
+  }
+
+  std::vector<std::pair<int, int>> fragments_;
+  std::vector<Action> actions_;
+  std::string body_;
+};
+
+inline template_t compile(const std::string& body) { return template_t(body); }
+namespace detail {
+inline std::string& get_template_base_directory_ref() {
+  static std::string template_base_directory = "templates";
+  return template_base_directory;
+}
+}
+
+inline std::string default_loader(const std::string& filename) {
+  std::string path = detail::get_template_base_directory_ref();
+  if (!(path.back() == '/' || path.back() == '\\')) path += '/';
+  path += filename;
+  std::ifstream inf(path);
+  if (!inf) return {};
+  return {std::istreambuf_iterator<char>(inf),
+          std::istreambuf_iterator<char>()};
+}
+
+namespace detail {
+inline std::function<std::string(std::string)>& get_loader_ref() {
+  static std::function<std::string(std::string)> loader = default_loader;
+  return loader;
+}
+}
+
+inline void set_base(const std::string& path) {
+  auto& base = detail::get_template_base_directory_ref();
+  base = path;
+  if (base.back() != '\\' && base.back() != '/') {
+    base += '/';
+  }
+}
+
+inline void set_loader(std::function<std::string(std::string)> loader) {
+  detail::get_loader_ref() = std::move(loader);
+}
+
+inline std::string load_text(const std::string& filename) {
+  return detail::get_loader_ref()(filename);
+}
+
+inline template_t load(const std::string& filename) {
+  return compile(detail::get_loader_ref()(filename));
+}
+}
+}
diff --git a/crow/include/crow/parser.h b/crow/include/crow/parser.h
new file mode 100644
index 0000000..8fffcfc
--- /dev/null
+++ b/crow/include/crow/parser.h
@@ -0,0 +1,138 @@
+#pragma once
+
+#include <algorithm>
+#include <boost/algorithm/string.hpp>
+#include <boost/tokenizer.hpp>
+#include <string>
+#include <unordered_map>
+
+#include "crow/http_parser_merged.h"
+#include "crow/http_request.h"
+
+namespace crow {
+template <typename Handler>
+struct HTTPParser : public http_parser {
+  static int on_message_begin(http_parser* self_) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    self->clear();
+    return 0;
+  }
+  static int on_url(http_parser* self_, const char* at, size_t length) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    self->raw_url.insert(self->raw_url.end(), at, at + length);
+    return 0;
+  }
+  static int on_header_field(http_parser* self_, const char* at,
+                             size_t length) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    switch (self->header_building_state) {
+      case 0:
+        if (!self->header_value.empty()) {
+          self->headers.emplace(std::move(self->header_field),
+                                std::move(self->header_value));
+        }
+        self->header_field.assign(at, at + length);
+        self->header_building_state = 1;
+        break;
+      case 1:
+        self->header_field.insert(self->header_field.end(), at, at + length);
+        break;
+    }
+    return 0;
+  }
+  static int on_header_value(http_parser* self_, const char* at,
+                             size_t length) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    switch (self->header_building_state) {
+      case 0:
+        self->header_value.insert(self->header_value.end(), at, at + length);
+        break;
+      case 1:
+        self->header_building_state = 0;
+        self->header_value.assign(at, at + length);
+        break;
+    }
+    return 0;
+  }
+  static int on_headers_complete(http_parser* self_) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    if (!self->header_field.empty()) {
+      self->headers.emplace(std::move(self->header_field),
+                            std::move(self->header_value));
+    }
+    self->process_header();
+    return 0;
+  }
+  static int on_body(http_parser* self_, const char* at, size_t length) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+    self->body.insert(self->body.end(), at, at + length);
+    return 0;
+  }
+  static int on_message_complete(http_parser* self_) {
+    HTTPParser* self = static_cast<HTTPParser*>(self_);
+
+    // url params
+    self->url = self->raw_url.substr(0, self->raw_url.find("?"));
+    self->url_params = query_string(self->raw_url);
+
+    self->process_message();
+    return 0;
+  }
+  HTTPParser(Handler* handler) : handler_(handler) {
+    http_parser_init(this, HTTP_REQUEST);
+  }
+
+  // return false on error
+  bool feed(const char* buffer, int length) {
+    const static http_parser_settings settings_{
+        on_message_begin, on_url,
+        nullptr,          on_header_field,
+        on_header_value,  on_headers_complete,
+        on_body,          on_message_complete,
+    };
+
+    int nparsed = http_parser_execute(this, &settings_, buffer, length);
+    return nparsed == length;
+  }
+
+  bool done() { return feed(nullptr, 0); }
+
+  void clear() {
+    url.clear();
+    raw_url.clear();
+    header_building_state = 0;
+    header_field.clear();
+    header_value.clear();
+    headers.clear();
+    url_params.clear();
+    body.clear();
+  }
+
+  void process_header() { handler_->handle_header(); }
+
+  void process_message() { handler_->handle(); }
+
+  request to_request() const {
+    return request{(HTTPMethod)method,    std::move(raw_url), std::move(url),
+                   std::move(url_params), std::move(headers), std::move(body)};
+  }
+
+  bool is_upgrade() const { return upgrade; }
+
+  bool check_version(int major, int minor) const {
+    return http_major == major && http_minor == minor;
+  }
+
+  std::string raw_url;
+  std::string url;
+
+  int header_building_state = 0;
+  std::string header_field;
+  std::string header_value;
+  ci_map headers;
+  query_string url_params;
+  std::string body;
+
+  Handler* handler_;
+};
+}
diff --git a/crow/include/crow/query_string.h b/crow/include/crow/query_string.h
new file mode 100644
index 0000000..2bdb216
--- /dev/null
+++ b/crow/include/crow/query_string.h
@@ -0,0 +1,313 @@
+#pragma once
+
+#include <stdio.h>
+#include <string.h>
+#include <iostream>
+#include <string>
+#include <vector>
+
+namespace crow {
+// ----------------------------------------------------------------------------
+// qs_parse (modified)
+// https://github.com/bartgrantham/qs_parse
+// ----------------------------------------------------------------------------
+/*  Similar to strncmp, but handles URL-encoding for either string  */
+int qs_strncmp(const char* s, const char* qs, size_t n);
+
+/*  Finds the beginning of each key/value pair and stores a pointer in qs_kv.
+ *  Also decodes the value portion of the k/v pair *in-place*.  In a future
+ *  enhancement it will also have a compile-time option of sorting qs_kv
+ *  alphabetically by key.  */
+int qs_parse(char* qs, char* qs_kv[], int qs_kv_size);
+
+/*  Used by qs_parse to decode the value portion of a k/v pair  */
+int qs_decode(char* qs);
+
+/*  Looks up the value according to the key on a pre-processed query string
+ *  A future enhancement will be a compile-time option to look up the key
+ *  in a pre-sorted qs_kv array via a binary search.  */
+// char * qs_k2v(const char * key, char * qs_kv[], int qs_kv_size);
+char* qs_k2v(const char* key, char* const* qs_kv, int qs_kv_size, int nth);
+
+/*  Non-destructive lookup of value, based on key.  User provides the
+ *  destinaton string and length.  */
+char* qs_scanvalue(const char* key, const char* qs, char* val, size_t val_len);
+
+// TODO: implement sorting of the qs_kv array; for now ensure it's not compiled
+#undef _qsSORTING
+
+// isxdigit _is_ available in <ctype.h>, but let's avoid another header instead
+#define CROW_QS_ISHEX(x)                                        \
+  ((((x) >= '0' && (x) <= '9') || ((x) >= 'A' && (x) <= 'F') || \
+    ((x) >= 'a' && (x) <= 'f'))                                 \
+       ? 1                                                      \
+       : 0)
+#define CROW_QS_HEX2DEC(x)                   \
+  (((x) >= '0' && (x) <= '9')                \
+       ? (x)-48                              \
+       : ((x) >= 'A' && (x) <= 'F') ? (x)-55 \
+                                    : ((x) >= 'a' && (x) <= 'f') ? (x)-87 : 0)
+#define CROW_QS_ISQSCHR(x) \
+  ((((x) == '=') || ((x) == '#') || ((x) == '&') || ((x) == '\0')) ? 0 : 1)
+
+inline int qs_strncmp(const char* s, const char* qs, size_t n) {
+  int i = 0;
+  unsigned char u1, u2, unyb, lnyb;
+
+  while (n-- > 0) {
+    u1 = (unsigned char)*s++;
+    u2 = (unsigned char)*qs++;
+
+    if (!CROW_QS_ISQSCHR(u1)) {
+      u1 = '\0';
+    }
+    if (!CROW_QS_ISQSCHR(u2)) {
+      u2 = '\0';
+    }
+
+    if (u1 == '+') {
+      u1 = ' ';
+    }
+    if (u1 == '%')  // easier/safer than scanf
+    {
+      unyb = (unsigned char)*s++;
+      lnyb = (unsigned char)*s++;
+      if (CROW_QS_ISHEX(unyb) && CROW_QS_ISHEX(lnyb))
+        u1 = (CROW_QS_HEX2DEC(unyb) * 16) + CROW_QS_HEX2DEC(lnyb);
+      else
+        u1 = '\0';
+    }
+
+    if (u2 == '+') {
+      u2 = ' ';
+    }
+    if (u2 == '%')  // easier/safer than scanf
+    {
+      unyb = (unsigned char)*qs++;
+      lnyb = (unsigned char)*qs++;
+      if (CROW_QS_ISHEX(unyb) && CROW_QS_ISHEX(lnyb))
+        u2 = (CROW_QS_HEX2DEC(unyb) * 16) + CROW_QS_HEX2DEC(lnyb);
+      else
+        u2 = '\0';
+    }
+
+    if (u1 != u2) return u1 - u2;
+    if (u1 == '\0') return 0;
+    i++;
+  }
+  if (CROW_QS_ISQSCHR(*qs))
+    return -1;
+  else
+    return 0;
+}
+
+inline int qs_parse(char* qs, char* qs_kv[], int qs_kv_size) {
+  int i, j;
+  char* substr_ptr;
+
+  for (i = 0; i < qs_kv_size; i++) qs_kv[i] = NULL;
+
+  // find the beginning of the k/v substrings or the fragment
+  substr_ptr = qs + strcspn(qs, "?#");
+  if (substr_ptr[0] != '\0')
+    substr_ptr++;
+  else
+    return 0;  // no query or fragment
+
+  i = 0;
+  while (i < qs_kv_size) {
+    qs_kv[i] = substr_ptr;
+    j = strcspn(substr_ptr, "&");
+    if (substr_ptr[j] == '\0') {
+      break;
+    }
+    substr_ptr += j + 1;
+    i++;
+  }
+  i++;  // x &'s -> means x iterations of this loop -> means *x+1* k/v pairs
+
+  // we only decode the values in place, the keys could have '='s in them
+  // which will hose our ability to distinguish keys from values later
+  for (j = 0; j < i; j++) {
+    substr_ptr = qs_kv[j] + strcspn(qs_kv[j], "=&#");
+    if (substr_ptr[0] == '&' ||
+        substr_ptr[0] == '\0')  // blank value: skip decoding
+      substr_ptr[0] = '\0';
+    else
+      qs_decode(++substr_ptr);
+  }
+
+#ifdef _qsSORTING
+// TODO: qsort qs_kv, using qs_strncmp() for the comparison
+#endif
+
+  return i;
+}
+
+inline int qs_decode(char* qs) {
+  int i = 0, j = 0;
+
+  while (CROW_QS_ISQSCHR(qs[j])) {
+    if (qs[j] == '+') {
+      qs[i] = ' ';
+    } else if (qs[j] == '%')  // easier/safer than scanf
+    {
+      if (!CROW_QS_ISHEX(qs[j + 1]) || !CROW_QS_ISHEX(qs[j + 2])) {
+        qs[i] = '\0';
+        return i;
+      }
+      qs[i] = (CROW_QS_HEX2DEC(qs[j + 1]) * 16) + CROW_QS_HEX2DEC(qs[j + 2]);
+      j += 2;
+    } else {
+      qs[i] = qs[j];
+    }
+    i++;
+    j++;
+  }
+  qs[i] = '\0';
+
+  return i;
+}
+
+inline char* qs_k2v(const char* key, char* const* qs_kv, int qs_kv_size,
+                    int nth = 0) {
+  int i;
+  size_t key_len, skip;
+
+  key_len = strlen(key);
+
+#ifdef _qsSORTING
+// TODO: binary search for key in the sorted qs_kv
+#else   // _qsSORTING
+  for (i = 0; i < qs_kv_size; i++) {
+    // we rely on the unambiguous '=' to find the value in our k/v pair
+    if (qs_strncmp(key, qs_kv[i], key_len) == 0) {
+      skip = strcspn(qs_kv[i], "=");
+      if (qs_kv[i][skip] == '=') skip++;
+      // return (zero-char value) ? ptr to trailing '\0' : ptr to value
+      if (nth == 0)
+        return qs_kv[i] + skip;
+      else
+        --nth;
+    }
+  }
+#endif  // _qsSORTING
+
+  return NULL;
+}
+
+inline char* qs_scanvalue(const char* key, const char* qs, char* val,
+                          size_t val_len) {
+  size_t i, key_len;
+  const char* tmp;
+
+  // find the beginning of the k/v substrings
+  if ((tmp = strchr(qs, '?')) != NULL) qs = tmp + 1;
+
+  key_len = strlen(key);
+  while (qs[0] != '#' && qs[0] != '\0') {
+    if (qs_strncmp(key, qs, key_len) == 0) break;
+    qs += strcspn(qs, "&") + 1;
+  }
+
+  if (qs[0] == '\0') return NULL;
+
+  qs += strcspn(qs, "=&#");
+  if (qs[0] == '=') {
+    qs++;
+    i = strcspn(qs, "&=#");
+    strncpy(val, qs, (val_len - 1) < (i + 1) ? (val_len - 1) : (i + 1));
+    qs_decode(val);
+  } else {
+    if (val_len > 0) val[0] = '\0';
+  }
+
+  return val;
+}
+}
+// ----------------------------------------------------------------------------
+
+namespace crow {
+class query_string {
+ public:
+  static const int MAX_KEY_VALUE_PAIRS_COUNT = 256;
+
+  query_string() {}
+
+  query_string(const query_string& qs) : url_(qs.url_) {
+    for (auto p : qs.key_value_pairs_) {
+      key_value_pairs_.push_back((char*)(p - qs.url_.c_str() + url_.c_str()));
+    }
+  }
+
+  query_string& operator=(const query_string& qs) {
+    url_ = qs.url_;
+    key_value_pairs_.clear();
+    for (auto p : qs.key_value_pairs_) {
+      key_value_pairs_.push_back((char*)(p - qs.url_.c_str() + url_.c_str()));
+    }
+    return *this;
+  }
+
+  query_string& operator=(query_string&& qs) {
+    key_value_pairs_ = std::move(qs.key_value_pairs_);
+    char* old_data = (char*)qs.url_.c_str();
+    url_ = std::move(qs.url_);
+    for (auto& p : key_value_pairs_) {
+      p += (char*)url_.c_str() - old_data;
+    }
+    return *this;
+  }
+
+  query_string(std::string url) : url_(std::move(url)) {
+    if (url_.empty()) return;
+
+    key_value_pairs_.resize(MAX_KEY_VALUE_PAIRS_COUNT);
+
+    int count =
+        qs_parse(&url_[0], &key_value_pairs_[0], MAX_KEY_VALUE_PAIRS_COUNT);
+    key_value_pairs_.resize(count);
+  }
+
+  void clear() {
+    key_value_pairs_.clear();
+    url_.clear();
+  }
+
+  friend std::ostream& operator<<(std::ostream& os, const query_string& qs) {
+    os << "[ ";
+    for (size_t i = 0; i < qs.key_value_pairs_.size(); ++i) {
+      if (i) os << ", ";
+      os << qs.key_value_pairs_[i];
+    }
+    os << " ]";
+    return os;
+  }
+
+  char* get(const std::string& name) const {
+    char* ret =
+        qs_k2v(name.c_str(), key_value_pairs_.data(), key_value_pairs_.size());
+    return ret;
+  }
+
+  std::vector<char*> get_list(const std::string& name) const {
+    std::vector<char*> ret;
+    std::string plus = name + "[]";
+    char* element = nullptr;
+
+    int count = 0;
+    while (1) {
+      element = qs_k2v(plus.c_str(), key_value_pairs_.data(),
+                       key_value_pairs_.size(), count++);
+      if (!element) break;
+      ret.push_back(element);
+    }
+    return ret;
+  }
+
+ private:
+  std::string url_;
+  std::vector<char*> key_value_pairs_;
+};
+
+}  // end namespace
diff --git a/crow/include/crow/routing.h b/crow/include/crow/routing.h
new file mode 100644
index 0000000..a82c34e
--- /dev/null
+++ b/crow/include/crow/routing.h
@@ -0,0 +1,947 @@
+#pragma once
+
+#include <boost/lexical_cast.hpp>
+#include <cstdint>
+#include <memory>
+#include <tuple>
+#include <unordered_map>
+#include <utility>
+#include <vector>
+
+#include "crow/common.h"
+#include "crow/http_request.h"
+#include "crow/http_response.h"
+#include "crow/logging.h"
+#include "crow/utility.h"
+#include "crow/websocket.h"
+
+namespace crow {
+class BaseRule {
+ public:
+  BaseRule(std::string rule) : rule_(std::move(rule)) {}
+
+  virtual ~BaseRule() {}
+
+  virtual void validate() = 0;
+  std::unique_ptr<BaseRule> upgrade() {
+    if (rule_to_upgrade_) return std::move(rule_to_upgrade_);
+    return {};
+  }
+
+  virtual void handle(const request&, response&, const routing_params&) = 0;
+  virtual void handle_upgrade(const request&, response& res, SocketAdaptor&&) {
+    res = response(404);
+    res.end();
+  }
+#ifdef CROW_ENABLE_SSL
+  virtual void handle_upgrade(const request&, response& res, SSLAdaptor&&) {
+    res = response(404);
+    res.end();
+  }
+#endif
+
+  uint32_t get_methods() { return methods_; }
+
+ protected:
+  uint32_t methods_{1 << (int)HTTPMethod::Get};
+
+  std::string rule_;
+  std::string name_;
+
+  std::unique_ptr<BaseRule> rule_to_upgrade_;
+
+  friend class Router;
+  template <typename T>
+  friend struct RuleParameterTraits;
+};
+
+namespace detail {
+namespace routing_handler_call_helper {
+template <typename T, int Pos>
+struct call_pair {
+  using type = T;
+  static const int pos = Pos;
+};
+
+template <typename H1>
+struct call_params {
+  H1& handler;
+  const routing_params& params;
+  const request& req;
+  response& res;
+};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename S1, typename S2>
+struct call {};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename... Args1, typename... Args2>
+struct call<F, NInt, NUint, NDouble, NString, black_magic::S<int64_t, Args1...>,
+            black_magic::S<Args2...>> {
+  void operator()(F cparams) {
+    using pushed = typename black_magic::S<Args2...>::template push_back<
+        call_pair<int64_t, NInt>>;
+    call<F, NInt + 1, NUint, NDouble, NString, black_magic::S<Args1...>,
+         pushed>()(cparams);
+  }
+};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename... Args1, typename... Args2>
+struct call<F, NInt, NUint, NDouble, NString,
+            black_magic::S<uint64_t, Args1...>, black_magic::S<Args2...>> {
+  void operator()(F cparams) {
+    using pushed = typename black_magic::S<Args2...>::template push_back<
+        call_pair<uint64_t, NUint>>;
+    call<F, NInt, NUint + 1, NDouble, NString, black_magic::S<Args1...>,
+         pushed>()(cparams);
+  }
+};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename... Args1, typename... Args2>
+struct call<F, NInt, NUint, NDouble, NString, black_magic::S<double, Args1...>,
+            black_magic::S<Args2...>> {
+  void operator()(F cparams) {
+    using pushed = typename black_magic::S<Args2...>::template push_back<
+        call_pair<double, NDouble>>;
+    call<F, NInt, NUint, NDouble + 1, NString, black_magic::S<Args1...>,
+         pushed>()(cparams);
+  }
+};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename... Args1, typename... Args2>
+struct call<F, NInt, NUint, NDouble, NString,
+            black_magic::S<std::string, Args1...>, black_magic::S<Args2...>> {
+  void operator()(F cparams) {
+    using pushed = typename black_magic::S<Args2...>::template push_back<
+        call_pair<std::string, NString>>;
+    call<F, NInt, NUint, NDouble, NString + 1, black_magic::S<Args1...>,
+         pushed>()(cparams);
+  }
+};
+
+template <typename F, int NInt, int NUint, int NDouble, int NString,
+          typename... Args1>
+struct call<F, NInt, NUint, NDouble, NString, black_magic::S<>,
+            black_magic::S<Args1...>> {
+  void operator()(F cparams) {
+    cparams.handler(
+        cparams.req, cparams.res,
+        cparams.params.template get<typename Args1::type>(Args1::pos)...);
+  }
+};
+
+template <typename Func, typename... ArgsWrapped>
+struct Wrapped {
+  template <typename... Args>
+  void set(Func f, typename std::enable_if<
+                       !std::is_same<typename std::tuple_element<
+                                         0, std::tuple<Args..., void>>::type,
+                                     const request&>::value,
+                       int>::type = 0) {
+    handler_ = (
+#ifdef CROW_CAN_USE_CPP14
+        [f = std::move(f)]
+#else
+        [f]
+#endif
+        (const request&, response& res, Args... args) {
+          res = response(f(args...));
+          res.end();
+        });
+  }
+
+  template <typename Req, typename... Args>
+  struct req_handler_wrapper {
+    req_handler_wrapper(Func f) : f(std::move(f)) {}
+
+    void operator()(const request& req, response& res, Args... args) {
+      res = response(f(req, args...));
+      res.end();
+    }
+
+    Func f;
+  };
+
+  template <typename... Args>
+  void set(
+      Func f,
+      typename std::enable_if<
+          std::is_same<
+              typename std::tuple_element<0, std::tuple<Args..., void>>::type,
+              const request&>::value &&
+              !std::is_same<typename std::tuple_element<
+                                1, std::tuple<Args..., void, void>>::type,
+                            response&>::value,
+          int>::type = 0) {
+    handler_ = req_handler_wrapper<Args...>(std::move(f));
+    /*handler_ = (
+        [f = std::move(f)]
+        (const request& req, response& res, Args... args){
+             res = response(f(req, args...));
+             res.end();
+        });*/
+  }
+
+  template <typename... Args>
+  void set(
+      Func f,
+      typename std::enable_if<
+          std::is_same<
+              typename std::tuple_element<0, std::tuple<Args..., void>>::type,
+              const request&>::value &&
+              std::is_same<typename std::tuple_element<
+                               1, std::tuple<Args..., void, void>>::type,
+                           response&>::value,
+          int>::type = 0) {
+    handler_ = std::move(f);
+  }
+
+  template <typename... Args>
+  struct handler_type_helper {
+    using type =
+        std::function<void(const crow::request&, crow::response&, Args...)>;
+    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>;
+  };
+
+  template <typename... Args>
+  struct handler_type_helper<const request&, Args...> {
+    using type =
+        std::function<void(const crow::request&, crow::response&, Args...)>;
+    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>;
+  };
+
+  template <typename... Args>
+  struct handler_type_helper<const request&, response&, Args...> {
+    using type =
+        std::function<void(const crow::request&, crow::response&, Args...)>;
+    using args_type = black_magic::S<typename black_magic::promote_t<Args>...>;
+  };
+
+  typename handler_type_helper<ArgsWrapped...>::type handler_;
+
+  void operator()(const request& req, response& res,
+                  const routing_params& params) {
+    detail::routing_handler_call_helper::call<
+        detail::routing_handler_call_helper::call_params<decltype(handler_)>, 0,
+        0, 0, 0, typename handler_type_helper<ArgsWrapped...>::args_type,
+        black_magic::S<>>()(
+        detail::routing_handler_call_helper::call_params<decltype(handler_)>{
+            handler_, params, req, res});
+  }
+};
+}
+}
+
+class WebSocketRule : public BaseRule {
+  using self_t = WebSocketRule;
+
+ public:
+  WebSocketRule(std::string rule) : BaseRule(std::move(rule)) {}
+
+  void validate() override {}
+
+  void handle(const request&, response& res, const routing_params&) override {
+    res = response(404);
+    res.end();
+  }
+
+  void handle_upgrade(const request& req, response&,
+                      SocketAdaptor&& adaptor) override {
+    new crow::websocket::Connection<SocketAdaptor>(
+        req, std::move(adaptor), open_handler_, message_handler_,
+        close_handler_, error_handler_);
+  }
+#ifdef CROW_ENABLE_SSL
+  void handle_upgrade(const request& req, response&,
+                      SSLAdaptor&& adaptor) override {
+    new crow::websocket::Connection<SSLAdaptor>(req, std::move(adaptor),
+                                                open_handler_, message_handler_,
+                                                close_handler_, error_handler_);
+  }
+#endif
+
+  template <typename Func>
+  self_t& onopen(Func f) {
+    open_handler_ = f;
+    return *this;
+  }
+
+  template <typename Func>
+  self_t& onmessage(Func f) {
+    message_handler_ = f;
+    return *this;
+  }
+
+  template <typename Func>
+  self_t& onclose(Func f) {
+    close_handler_ = f;
+    return *this;
+  }
+
+  template <typename Func>
+  self_t& onerror(Func f) {
+    error_handler_ = f;
+    return *this;
+  }
+
+ protected:
+  std::function<void(crow::websocket::connection&)> open_handler_;
+  std::function<void(crow::websocket::connection&, const std::string&, bool)>
+      message_handler_;
+  std::function<void(crow::websocket::connection&, const std::string&)>
+      close_handler_;
+  std::function<void(crow::websocket::connection&)> error_handler_;
+};
+
+template <typename T>
+struct RuleParameterTraits {
+  using self_t = T;
+  WebSocketRule& websocket() {
+    auto p = new WebSocketRule(((self_t*)this)->rule_);
+    ((self_t*)this)->rule_to_upgrade_.reset(p);
+    return *p;
+  }
+
+  self_t& name(std::string name) noexcept {
+    ((self_t*)this)->name_ = std::move(name);
+    return (self_t&)*this;
+  }
+
+  self_t& methods(HTTPMethod method) {
+    ((self_t*)this)->methods_ = 1 << (int)method;
+    return (self_t&)*this;
+  }
+
+  template <typename... MethodArgs>
+  self_t& methods(HTTPMethod method, MethodArgs... args_method) {
+    methods(args_method...);
+    ((self_t*)this)->methods_ |= 1 << (int)method;
+    return (self_t&)*this;
+  }
+};
+
+class DynamicRule : public BaseRule, public RuleParameterTraits<DynamicRule> {
+ public:
+  DynamicRule(std::string rule) : BaseRule(std::move(rule)) {}
+
+  void validate() override {
+    if (!erased_handler_) {
+      throw std::runtime_error(name_ + (!name_.empty() ? ": " : "") +
+                               "no handler for url " + rule_);
+    }
+  }
+
+  void handle(const request& req, response& res,
+              const routing_params& params) override {
+    erased_handler_(req, res, params);
+  }
+
+  template <typename Func>
+  void operator()(Func f) {
+#ifdef CROW_MSVC_WORKAROUND
+    using function_t = utility::function_traits<decltype(&Func::operator())>;
+#else
+    using function_t = utility::function_traits<Func>;
+#endif
+    erased_handler_ =
+        wrap(std::move(f), black_magic::gen_seq<function_t::arity>());
+  }
+
+// enable_if Arg1 == request && Arg2 == response
+// enable_if Arg1 == request && Arg2 != resposne
+// enable_if Arg1 != request
+#ifdef CROW_MSVC_WORKAROUND
+  template <typename Func, size_t... Indices>
+#else
+  template <typename Func, unsigned... Indices>
+#endif
+  std::function<void(const request&, response&, const routing_params&)> wrap(
+      Func f, black_magic::seq<Indices...>) {
+#ifdef CROW_MSVC_WORKAROUND
+    using function_t = utility::function_traits<decltype(&Func::operator())>;
+#else
+    using function_t = utility::function_traits<Func>;
+#endif
+    if (!black_magic::is_parameter_tag_compatible(
+            black_magic::get_parameter_tag_runtime(rule_.c_str()),
+            black_magic::compute_parameter_tag_from_args_list<
+                typename function_t::template arg<Indices>...>::value)) {
+      throw std::runtime_error(
+          "route_dynamic: Handler type is mismatched with URL parameters: " +
+          rule_);
+    }
+    auto ret = detail::routing_handler_call_helper::Wrapped<
+        Func, typename function_t::template arg<Indices>...>();
+    ret.template set<typename function_t::template arg<Indices>...>(
+        std::move(f));
+    return ret;
+  }
+
+  template <typename Func>
+  void operator()(std::string name, Func&& f) {
+    name_ = std::move(name);
+    (*this).template operator()<Func>(std::forward(f));
+  }
+
+ private:
+  std::function<void(const request&, response&, const routing_params&)>
+      erased_handler_;
+};
+
+template <typename... Args>
+class TaggedRule : public BaseRule,
+                   public RuleParameterTraits<TaggedRule<Args...>> {
+ public:
+  using self_t = TaggedRule<Args...>;
+
+  TaggedRule(std::string rule) : BaseRule(std::move(rule)) {}
+
+  void validate() override {
+    if (!handler_) {
+      throw std::runtime_error(name_ + (!name_.empty() ? ": " : "") +
+                               "no handler for url " + rule_);
+    }
+  }
+
+  template <typename Func>
+  typename std::enable_if<
+      black_magic::CallHelper<Func, black_magic::S<Args...>>::value, void>::type
+  operator()(Func&& f) {
+    static_assert(
+        black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+            black_magic::CallHelper<
+                Func, black_magic::S<crow::request, Args...>>::value,
+        "Handler type is mismatched with URL parameters");
+    static_assert(
+        !std::is_same<void, decltype(f(std::declval<Args>()...))>::value,
+        "Handler function cannot have void return type; valid return types: "
+        "string, int, crow::resposne, crow::json::wvalue");
+
+    handler_ = [f = std::move(f)](const request&, response& res, Args... args) {
+      res = response(f(args...));
+      res.end();
+    };
+  }
+
+  template <typename Func>
+  typename std::enable_if<
+      !black_magic::CallHelper<Func, black_magic::S<Args...>>::value &&
+          black_magic::CallHelper<
+              Func, black_magic::S<crow::request, Args...>>::value,
+      void>::type
+  operator()(Func&& f) {
+    static_assert(
+        black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+            black_magic::CallHelper<
+                Func, black_magic::S<crow::request, Args...>>::value,
+        "Handler type is mismatched with URL parameters");
+    static_assert(
+        !std::is_same<void, decltype(f(std::declval<crow::request>(),
+                                       std::declval<Args>()...))>::value,
+        "Handler function cannot have void return type; valid return types: "
+        "string, int, crow::resposne, crow::json::wvalue");
+
+    handler_ = [f = std::move(f)](const crow::request& req, crow::response& res,
+                                  Args... args) {
+      res = response(f(req, args...));
+      res.end();
+    };
+  }
+
+  template <typename Func>
+  typename std::enable_if<
+      !black_magic::CallHelper<Func, black_magic::S<Args...>>::value &&
+          !black_magic::CallHelper<
+              Func, black_magic::S<crow::request, Args...>>::value,
+      void>::type
+  operator()(Func&& f) {
+    static_assert(
+        black_magic::CallHelper<Func, black_magic::S<Args...>>::value ||
+            black_magic::CallHelper<
+                Func, black_magic::S<crow::request, Args...>>::value ||
+            black_magic::CallHelper<
+                Func,
+                black_magic::S<crow::request, crow::response&, Args...>>::value,
+        "Handler type is mismatched with URL parameters");
+    static_assert(
+        std::is_same<void, decltype(f(std::declval<crow::request>(),
+                                      std::declval<crow::response&>(),
+                                      std::declval<Args>()...))>::value,
+        "Handler function with response argument should have void return type");
+
+    handler_ = std::move(f);
+  }
+
+  template <typename Func>
+  void operator()(std::string name, Func&& f) {
+    name_ = std::move(name);
+    (*this).template operator()<Func>(std::forward(f));
+  }
+
+  void handle(const request& req, response& res,
+              const routing_params& params) override {
+    detail::routing_handler_call_helper::call<
+        detail::routing_handler_call_helper::call_params<decltype(handler_)>, 0,
+        0, 0, 0, black_magic::S<Args...>, black_magic::S<>>()(
+        detail::routing_handler_call_helper::call_params<decltype(handler_)>{
+            handler_, params, req, res});
+  }
+
+ private:
+  std::function<void(const crow::request&, crow::response&, Args...)> handler_;
+};
+
+const int RULE_SPECIAL_REDIRECT_SLASH = 1;
+
+class Trie {
+ public:
+  struct Node {
+    unsigned rule_index{};
+    std::array<unsigned, (int)ParamType::MAX> param_childrens{};
+    std::unordered_map<std::string, unsigned> children;
+
+    bool IsSimpleNode() const {
+      return !rule_index &&
+             std::all_of(std::begin(param_childrens), std::end(param_childrens),
+                         [](unsigned x) { return !x; });
+    }
+  };
+
+  Trie() : nodes_(1) {}
+
+ private:
+  void optimizeNode(Node* node) {
+    for (auto x : node->param_childrens) {
+      if (!x) continue;
+      Node* child = &nodes_[x];
+      optimizeNode(child);
+    }
+    if (node->children.empty()) return;
+    bool mergeWithChild = true;
+    for (auto& kv : node->children) {
+      Node* child = &nodes_[kv.second];
+      if (!child->IsSimpleNode()) {
+        mergeWithChild = false;
+        break;
+      }
+    }
+    if (mergeWithChild) {
+      decltype(node->children) merged;
+      for (auto& kv : node->children) {
+        Node* child = &nodes_[kv.second];
+        for (auto& child_kv : child->children) {
+          merged[kv.first + child_kv.first] = child_kv.second;
+        }
+      }
+      node->children = std::move(merged);
+      optimizeNode(node);
+    } else {
+      for (auto& kv : node->children) {
+        Node* child = &nodes_[kv.second];
+        optimizeNode(child);
+      }
+    }
+  }
+
+  void optimize() { optimizeNode(head()); }
+
+ public:
+  void validate() {
+    if (!head()->IsSimpleNode())
+      throw std::runtime_error("Internal error: Trie header should be simple!");
+    optimize();
+  }
+
+  std::pair<unsigned, routing_params> find(
+      const std::string& req_url, const Node* node = nullptr, unsigned pos = 0,
+      routing_params* params = nullptr) const {
+    routing_params empty;
+    if (params == nullptr) params = &empty;
+
+    unsigned found{};
+    routing_params match_params;
+
+    if (node == nullptr) node = head();
+    if (pos == req_url.size()) return {node->rule_index, *params};
+
+    auto update_found =
+        [&found, &match_params](std::pair<unsigned, routing_params>& ret) {
+          if (ret.first && (!found || found > ret.first)) {
+            found = ret.first;
+            match_params = std::move(ret.second);
+          }
+        };
+
+    if (node->param_childrens[(int)ParamType::INT]) {
+      char c = req_url[pos];
+      if ((c >= '0' && c <= '9') || c == '+' || c == '-') {
+        char* eptr;
+        errno = 0;
+        long long int value = strtoll(req_url.data() + pos, &eptr, 10);
+        if (errno != ERANGE && eptr != req_url.data() + pos) {
+          params->int_params.push_back(value);
+          auto ret =
+              find(req_url, &nodes_[node->param_childrens[(int)ParamType::INT]],
+                   eptr - req_url.data(), params);
+          update_found(ret);
+          params->int_params.pop_back();
+        }
+      }
+    }
+
+    if (node->param_childrens[(int)ParamType::UINT]) {
+      char c = req_url[pos];
+      if ((c >= '0' && c <= '9') || c == '+') {
+        char* eptr;
+        errno = 0;
+        unsigned long long int value =
+            strtoull(req_url.data() + pos, &eptr, 10);
+        if (errno != ERANGE && eptr != req_url.data() + pos) {
+          params->uint_params.push_back(value);
+          auto ret = find(req_url,
+                          &nodes_[node->param_childrens[(int)ParamType::UINT]],
+                          eptr - req_url.data(), params);
+          update_found(ret);
+          params->uint_params.pop_back();
+        }
+      }
+    }
+
+    if (node->param_childrens[(int)ParamType::DOUBLE]) {
+      char c = req_url[pos];
+      if ((c >= '0' && c <= '9') || c == '+' || c == '-' || c == '.') {
+        char* eptr;
+        errno = 0;
+        double value = strtod(req_url.data() + pos, &eptr);
+        if (errno != ERANGE && eptr != req_url.data() + pos) {
+          params->double_params.push_back(value);
+          auto ret = find(
+              req_url, &nodes_[node->param_childrens[(int)ParamType::DOUBLE]],
+              eptr - req_url.data(), params);
+          update_found(ret);
+          params->double_params.pop_back();
+        }
+      }
+    }
+
+    if (node->param_childrens[(int)ParamType::STRING]) {
+      size_t epos = pos;
+      for (; epos < req_url.size(); epos++) {
+        if (req_url[epos] == '/') break;
+      }
+
+      if (epos != pos) {
+        params->string_params.push_back(req_url.substr(pos, epos - pos));
+        auto ret = find(req_url,
+                        &nodes_[node->param_childrens[(int)ParamType::STRING]],
+                        epos, params);
+        update_found(ret);
+        params->string_params.pop_back();
+      }
+    }
+
+    if (node->param_childrens[(int)ParamType::PATH]) {
+      size_t epos = req_url.size();
+
+      if (epos != pos) {
+        params->string_params.push_back(req_url.substr(pos, epos - pos));
+        auto ret =
+            find(req_url, &nodes_[node->param_childrens[(int)ParamType::PATH]],
+                 epos, params);
+        update_found(ret);
+        params->string_params.pop_back();
+      }
+    }
+
+    for (auto& kv : node->children) {
+      const std::string& fragment = kv.first;
+      const Node* child = &nodes_[kv.second];
+
+      if (req_url.compare(pos, fragment.size(), fragment) == 0) {
+        auto ret = find(req_url, child, pos + fragment.size(), params);
+        update_found(ret);
+      }
+    }
+
+    return {found, match_params};
+  }
+
+  void add(const std::string& url, unsigned rule_index) {
+    unsigned idx{0};
+
+    for (unsigned i = 0; i < url.size(); i++) {
+      char c = url[i];
+      if (c == '<') {
+        static struct ParamTraits {
+          ParamType type;
+          std::string name;
+        } paramTraits[] = {
+            {ParamType::INT, "<int>"},      {ParamType::UINT, "<uint>"},
+            {ParamType::DOUBLE, "<float>"}, {ParamType::DOUBLE, "<double>"},
+            {ParamType::STRING, "<str>"},   {ParamType::STRING, "<string>"},
+            {ParamType::PATH, "<path>"},
+        };
+
+        for (auto& x : paramTraits) {
+          if (url.compare(i, x.name.size(), x.name) == 0) {
+            if (!nodes_[idx].param_childrens[(int)x.type]) {
+              auto new_node_idx = new_node();
+              nodes_[idx].param_childrens[(int)x.type] = new_node_idx;
+            }
+            idx = nodes_[idx].param_childrens[(int)x.type];
+            i += x.name.size();
+            break;
+          }
+        }
+
+        i--;
+      } else {
+        std::string piece(&c, 1);
+        if (!nodes_[idx].children.count(piece)) {
+          auto new_node_idx = new_node();
+          nodes_[idx].children.emplace(piece, new_node_idx);
+        }
+        idx = nodes_[idx].children[piece];
+      }
+    }
+    if (nodes_[idx].rule_index)
+      throw std::runtime_error("handler already exists for " + url);
+    nodes_[idx].rule_index = rule_index;
+  }
+
+ private:
+  void debug_node_print(Node* n, int level) {
+    for (int i = 0; i < (int)ParamType::MAX; i++) {
+      if (n->param_childrens[i]) {
+        CROW_LOG_DEBUG << std::string(
+            2 * level, ' ') /*<< "("<<n->param_childrens[i]<<") "*/;
+        switch ((ParamType)i) {
+          case ParamType::INT:
+            CROW_LOG_DEBUG << "<int>";
+            break;
+          case ParamType::UINT:
+            CROW_LOG_DEBUG << "<uint>";
+            break;
+          case ParamType::DOUBLE:
+            CROW_LOG_DEBUG << "<float>";
+            break;
+          case ParamType::STRING:
+            CROW_LOG_DEBUG << "<str>";
+            break;
+          case ParamType::PATH:
+            CROW_LOG_DEBUG << "<path>";
+            break;
+          default:
+            CROW_LOG_DEBUG << "<ERROR>";
+            break;
+        }
+
+        debug_node_print(&nodes_[n->param_childrens[i]], level + 1);
+      }
+    }
+    for (auto& kv : n->children) {
+      CROW_LOG_DEBUG << std::string(2 * level,
+                                    ' ') /*<< "(" << kv.second << ") "*/
+                     << kv.first;
+      debug_node_print(&nodes_[kv.second], level + 1);
+    }
+  }
+
+ public:
+  void debug_print() { debug_node_print(head(), 0); }
+
+ private:
+  const Node* head() const { return &nodes_.front(); }
+
+  Node* head() { return &nodes_.front(); }
+
+  unsigned new_node() {
+    nodes_.resize(nodes_.size() + 1);
+    return nodes_.size() - 1;
+  }
+
+  std::vector<Node> nodes_;
+};
+
+class Router {
+ public:
+  Router() : rules_(2) {}
+
+  DynamicRule& new_rule_dynamic(const std::string& rule) {
+    auto ruleObject = new DynamicRule(rule);
+
+    internal_add_rule_object(rule, ruleObject);
+
+    return *ruleObject;
+  }
+
+  template <uint64_t N>
+  typename black_magic::arguments<N>::type::template rebind<TaggedRule>&
+  new_rule_tagged(const std::string& rule) {
+    using RuleT =
+        typename black_magic::arguments<N>::type::template rebind<TaggedRule>;
+    auto ruleObject = new RuleT(rule);
+
+    internal_add_rule_object(rule, ruleObject);
+
+    return *ruleObject;
+  }
+
+  void internal_add_rule_object(const std::string& rule, BaseRule* ruleObject) {
+    rules_.emplace_back(ruleObject);
+    trie_.add(rule, rules_.size() - 1);
+
+    // directory case:
+    //   request to `/about' url matches `/about/' rule
+    if (rule.size() > 1 && rule.back() == '/') {
+      std::string rule_without_trailing_slash = rule;
+      rule_without_trailing_slash.pop_back();
+      trie_.add(rule_without_trailing_slash, RULE_SPECIAL_REDIRECT_SLASH);
+    }
+  }
+
+  void validate() {
+    trie_.validate();
+    for (auto& rule : rules_) {
+      if (rule) {
+        auto upgraded = rule->upgrade();
+        if (upgraded) rule = std::move(upgraded);
+        rule->validate();
+      }
+    }
+  }
+
+  template <typename Adaptor>
+  void handle_upgrade(const request& req, response& res, Adaptor&& adaptor) {
+    auto found = trie_.find(req.url);
+    unsigned rule_index = found.first;
+    if (!rule_index) {
+      CROW_LOG_DEBUG << "Cannot match rules " << req.url;
+      res = response(404);
+      res.end();
+      return;
+    }
+
+    if (rule_index >= rules_.size())
+      throw std::runtime_error("Trie internal structure corrupted!");
+
+    if (rule_index == RULE_SPECIAL_REDIRECT_SLASH) {
+      CROW_LOG_INFO << "Redirecting to a url with trailing slash: " << req.url;
+      res = response(301);
+
+      // TODO absolute url building
+      if (req.get_header_value("Host").empty()) {
+        res.add_header("Location", req.url + "/");
+      } else {
+        res.add_header("Location", "http://" + req.get_header_value("Host") +
+                                       req.url + "/");
+      }
+      res.end();
+      return;
+    }
+
+    if ((rules_[rule_index]->get_methods() & (1 << (uint32_t)req.method)) ==
+        0) {
+      CROW_LOG_DEBUG << "Rule found but method mismatch: " << req.url
+                     << " with " << method_name(req.method) << "("
+                     << (uint32_t)req.method << ") / "
+                     << rules_[rule_index]->get_methods();
+      res = response(404);
+      res.end();
+      return;
+    }
+
+    CROW_LOG_DEBUG << "Matched rule (upgrade) '" << rules_[rule_index]->rule_
+                   << "' " << (uint32_t)req.method << " / "
+                   << rules_[rule_index]->get_methods();
+
+    // any uncaught exceptions become 500s
+    try {
+      rules_[rule_index]->handle_upgrade(req, res, std::move(adaptor));
+    } catch (std::exception& e) {
+      CROW_LOG_ERROR << "An uncaught exception occurred: " << e.what();
+      res = response(500);
+      res.end();
+      return;
+    } catch (...) {
+      CROW_LOG_ERROR << "An uncaught exception occurred. The type was unknown "
+                        "so no information was available.";
+      res = response(500);
+      res.end();
+      return;
+    }
+  }
+
+  void handle(const request& req, response& res) {
+    auto found = trie_.find(req.url);
+
+    unsigned rule_index = found.first;
+
+    if (!rule_index) {
+      CROW_LOG_DEBUG << "Cannot match rules " << req.url;
+      res = response(404);
+      res.end();
+      return;
+    }
+
+    if (rule_index >= rules_.size())
+      throw std::runtime_error("Trie internal structure corrupted!");
+
+    if (rule_index == RULE_SPECIAL_REDIRECT_SLASH) {
+      CROW_LOG_INFO << "Redirecting to a url with trailing slash: " << req.url;
+      res = response(301);
+
+      // TODO absolute url building
+      if (req.get_header_value("Host").empty()) {
+        res.add_header("Location", req.url + "/");
+      } else {
+        res.add_header("Location", "http://" + req.get_header_value("Host") +
+                                       req.url + "/");
+      }
+      res.end();
+      return;
+    }
+
+    if ((rules_[rule_index]->get_methods() & (1 << (uint32_t)req.method)) ==
+        0) {
+      CROW_LOG_DEBUG << "Rule found but method mismatch: " << req.url
+                     << " with " << method_name(req.method) << "("
+                     << (uint32_t)req.method << ") / "
+                     << rules_[rule_index]->get_methods();
+      res = response(404);
+      res.end();
+      return;
+    }
+
+    CROW_LOG_DEBUG << "Matched rule '" << rules_[rule_index]->rule_ << "' "
+                   << (uint32_t)req.method << " / "
+                   << rules_[rule_index]->get_methods();
+
+    // any uncaught exceptions become 500s
+    try {
+      rules_[rule_index]->handle(req, res, found.second);
+    } catch (std::exception& e) {
+      CROW_LOG_ERROR << "An uncaught exception occurred: " << e.what();
+      res = response(500);
+      res.end();
+      return;
+    } catch (...) {
+      CROW_LOG_ERROR << "An uncaught exception occurred. The type was unknown "
+                        "so no information was available.";
+      res = response(500);
+      res.end();
+      return;
+    }
+  }
+
+  void debug_print() { trie_.debug_print(); }
+
+ private:
+  std::vector<std::unique_ptr<BaseRule>> rules_;
+  Trie trie_;
+};
+}
diff --git a/crow/include/crow/settings.h b/crow/include/crow/settings.h
new file mode 100644
index 0000000..86a2474
--- /dev/null
+++ b/crow/include/crow/settings.h
@@ -0,0 +1,37 @@
+#pragma once
+// settings for crow
+// TODO - replace with runtime config. libucl?
+
+/* #ifdef - enables debug mode */
+#define CROW_ENABLE_DEBUG
+
+/* #ifdef - enables logging */
+#define CROW_ENABLE_LOGGING
+
+/* #ifdef - enables ssl */
+//#define CROW_ENABLE_SSL
+
+/* #define - specifies log level */
+/*
+    Debug       = 0
+    Info        = 1
+    Warning     = 2
+    Error       = 3
+    Critical    = 4
+
+    default to INFO
+*/
+#define CROW_LOG_LEVEL 1
+
+// compiler flags
+#if __cplusplus >= 201402L
+#define CROW_CAN_USE_CPP14
+#endif
+
+#if defined(_MSC_VER)
+#if _MSC_VER < 1900
+#define CROW_MSVC_WORKAROUND
+#define constexpr const
+#define noexcept throw()
+#endif
+#endif
diff --git a/crow/include/crow/socket_adaptors.h b/crow/include/crow/socket_adaptors.h
new file mode 100644
index 0000000..fe1bb93
--- /dev/null
+++ b/crow/include/crow/socket_adaptors.h
@@ -0,0 +1,69 @@
+#pragma once
+#include <boost/asio.hpp>
+#ifdef CROW_ENABLE_SSL
+#include <boost/asio/ssl.hpp>
+#endif
+#include "crow/settings.h"
+namespace crow {
+using namespace boost;
+using tcp = asio::ip::tcp;
+
+struct SocketAdaptor {
+  using context = void;
+  SocketAdaptor(boost::asio::io_service& io_service, context*)
+      : socket_(io_service) {}
+
+  boost::asio::io_service& get_io_service() { return socket_.get_io_service(); }
+
+  tcp::socket& raw_socket() { return socket_; }
+
+  tcp::socket& socket() { return socket_; }
+
+  tcp::endpoint remote_endpoint() { return socket_.remote_endpoint(); }
+
+  bool is_open() { return socket_.is_open(); }
+
+  void close() { socket_.close(); }
+
+  template <typename F>
+  void start(F f) {
+    f(boost::system::error_code());
+  }
+
+  tcp::socket socket_;
+};
+
+#ifdef CROW_ENABLE_SSL
+struct SSLAdaptor {
+  using context = boost::asio::ssl::context;
+  using ssl_socket_t = boost::asio::ssl::stream<tcp::socket>;
+  SSLAdaptor(boost::asio::io_service& io_service, context* ctx)
+      : ssl_socket_(new ssl_socket_t(io_service, *ctx)) {}
+
+  boost::asio::ssl::stream<tcp::socket>& socket() { return *ssl_socket_; }
+
+  tcp::socket::lowest_layer_type& raw_socket() {
+    return ssl_socket_->lowest_layer();
+  }
+
+  tcp::endpoint remote_endpoint() { return raw_socket().remote_endpoint(); }
+
+  bool is_open() { return raw_socket().is_open(); }
+
+  void close() { raw_socket().close(); }
+
+  boost::asio::io_service& get_io_service() {
+    return raw_socket().get_io_service();
+  }
+
+  template <typename F>
+  void start(F f) {
+    ssl_socket_->async_handshake(
+        boost::asio::ssl::stream_base::server,
+        [f](const boost::system::error_code& ec) { f(ec); });
+  }
+
+  std::unique_ptr<boost::asio::ssl::stream<tcp::socket>> ssl_socket_;
+};
+#endif
+}
diff --git a/crow/include/crow/utility.h b/crow/include/crow/utility.h
new file mode 100644
index 0000000..9ce4a93
--- /dev/null
+++ b/crow/include/crow/utility.h
@@ -0,0 +1,513 @@
+#pragma once
+
+#include <cstdint>
+#include <cstring>
+#include <functional>
+#include <stdexcept>
+#include <string>
+#include <tuple>
+#include <type_traits>
+
+#include "crow/settings.h"
+
+namespace crow {
+namespace black_magic {
+#ifndef CROW_MSVC_WORKAROUND
+struct OutOfRange {
+  OutOfRange(unsigned /*pos*/, unsigned /*length*/) {}
+};
+constexpr unsigned requires_in_range(unsigned i, unsigned len) {
+  return i >= len ? throw OutOfRange(i, len) : i;
+}
+
+class const_str {
+  const char* const begin_;
+  unsigned size_;
+
+ public:
+  template <unsigned N>
+  constexpr const_str(const char (&arr)[N]) : begin_(arr), size_(N - 1) {
+    static_assert(N >= 1, "not a string literal");
+  }
+  constexpr char operator[](unsigned i) const {
+    return requires_in_range(i, size_), begin_[i];
+  }
+
+  constexpr operator const char*() const { return begin_; }
+
+  constexpr const char* begin() const { return begin_; }
+  constexpr const char* end() const { return begin_ + size_; }
+
+  constexpr unsigned size() const { return size_; }
+};
+
+constexpr unsigned find_closing_tag(const_str s, unsigned p) {
+  return s[p] == '>' ? p : find_closing_tag(s, p + 1);
+}
+
+constexpr bool is_valid(const_str s, unsigned i = 0, int f = 0) {
+  return i == s.size() ? f == 0 : f < 0 || f >= 2
+                                      ? false
+                                      : s[i] == '<'
+                                            ? is_valid(s, i + 1, f + 1)
+                                            : s[i] == '>'
+                                                  ? is_valid(s, i + 1, f - 1)
+                                                  : is_valid(s, i + 1, f);
+}
+
+constexpr bool is_equ_p(const char* a, const char* b, unsigned n) {
+  return *a == 0 && *b == 0 && n == 0
+             ? true
+             : (*a == 0 || *b == 0)
+                   ? false
+                   : n == 0 ? true : *a != *b ? false
+                                              : is_equ_p(a + 1, b + 1, n - 1);
+}
+
+constexpr bool is_equ_n(const_str a, unsigned ai, const_str b, unsigned bi,
+                        unsigned n) {
+  return ai + n > a.size() || bi + n > b.size()
+             ? false
+             : n == 0 ? true : a[ai] != b[bi] ? false : is_equ_n(a, ai + 1, b,
+                                                                 bi + 1, n - 1);
+}
+
+constexpr bool is_int(const_str s, unsigned i) {
+  return is_equ_n(s, i, "<int>", 0, 5);
+}
+
+constexpr bool is_uint(const_str s, unsigned i) {
+  return is_equ_n(s, i, "<uint>", 0, 6);
+}
+
+constexpr bool is_float(const_str s, unsigned i) {
+  return is_equ_n(s, i, "<float>", 0, 7) || is_equ_n(s, i, "<double>", 0, 8);
+}
+
+constexpr bool is_str(const_str s, unsigned i) {
+  return is_equ_n(s, i, "<str>", 0, 5) || is_equ_n(s, i, "<string>", 0, 8);
+}
+
+constexpr bool is_path(const_str s, unsigned i) {
+  return is_equ_n(s, i, "<path>", 0, 6);
+}
+#endif
+template <typename T>
+struct parameter_tag {
+  static const int value = 0;
+};
+#define CROW_INTERNAL_PARAMETER_TAG(t, i) \
+  template <>                             \
+  struct parameter_tag<t> {               \
+    static const int value = i;           \
+  }
+CROW_INTERNAL_PARAMETER_TAG(int, 1);
+CROW_INTERNAL_PARAMETER_TAG(char, 1);
+CROW_INTERNAL_PARAMETER_TAG(short, 1);
+CROW_INTERNAL_PARAMETER_TAG(long, 1);
+CROW_INTERNAL_PARAMETER_TAG(long long, 1);
+CROW_INTERNAL_PARAMETER_TAG(unsigned int, 2);
+CROW_INTERNAL_PARAMETER_TAG(unsigned char, 2);
+CROW_INTERNAL_PARAMETER_TAG(unsigned short, 2);
+CROW_INTERNAL_PARAMETER_TAG(unsigned long, 2);
+CROW_INTERNAL_PARAMETER_TAG(unsigned long long, 2);
+CROW_INTERNAL_PARAMETER_TAG(double, 3);
+CROW_INTERNAL_PARAMETER_TAG(std::string, 4);
+#undef CROW_INTERNAL_PARAMETER_TAG
+template <typename... Args>
+struct compute_parameter_tag_from_args_list;
+
+template <>
+struct compute_parameter_tag_from_args_list<> {
+  static const int value = 0;
+};
+
+template <typename Arg, typename... Args>
+struct compute_parameter_tag_from_args_list<Arg, Args...> {
+  static const int sub_value =
+      compute_parameter_tag_from_args_list<Args...>::value;
+  static const int value =
+      parameter_tag<typename std::decay<Arg>::type>::value
+          ? sub_value * 6 + parameter_tag<typename std::decay<Arg>::type>::value
+          : sub_value;
+};
+
+static inline bool is_parameter_tag_compatible(uint64_t a, uint64_t b) {
+  if (a == 0) return b == 0;
+  if (b == 0) return a == 0;
+  int sa = a % 6;
+  int sb = a % 6;
+  if (sa == 5) sa = 4;
+  if (sb == 5) sb = 4;
+  if (sa != sb) return false;
+  return is_parameter_tag_compatible(a / 6, b / 6);
+}
+
+static inline unsigned find_closing_tag_runtime(const char* s, unsigned p) {
+  return s[p] == 0 ? throw std::runtime_error("unmatched tag <")
+                   : s[p] == '>' ? p : find_closing_tag_runtime(s, p + 1);
+}
+
+static inline uint64_t get_parameter_tag_runtime(const char* s,
+                                                 unsigned p = 0) {
+  return s[p] == 0
+             ? 0
+             : s[p] == '<'
+                   ? (std::strncmp(s + p, "<int>", 5) == 0
+                          ? get_parameter_tag_runtime(
+                                s, find_closing_tag_runtime(s, p)) *
+                                    6 +
+                                1
+                          : std::strncmp(s + p, "<uint>", 6) == 0
+                                ? get_parameter_tag_runtime(
+                                      s, find_closing_tag_runtime(s, p)) *
+                                          6 +
+                                      2
+                                : (std::strncmp(s + p, "<float>", 7) == 0 ||
+                                   std::strncmp(s + p, "<double>", 8) == 0)
+                                      ? get_parameter_tag_runtime(
+                                            s, find_closing_tag_runtime(s, p)) *
+                                                6 +
+                                            3
+                                      : (std::strncmp(s + p, "<str>", 5) == 0 ||
+                                         std::strncmp(s + p, "<string>", 8) ==
+                                             0)
+                                            ? get_parameter_tag_runtime(
+                                                  s, find_closing_tag_runtime(
+                                                         s, p)) *
+                                                      6 +
+                                                  4
+                                            : std::strncmp(s + p, "<path>",
+                                                           6) == 0
+                                                  ? get_parameter_tag_runtime(
+                                                        s,
+                                                        find_closing_tag_runtime(
+                                                            s, p)) *
+                                                            6 +
+                                                        5
+                                                  : throw std::runtime_error(
+                                                        "invalid parameter "
+                                                        "type"))
+                   : get_parameter_tag_runtime(s, p + 1);
+}
+#ifndef CROW_MSVC_WORKAROUND
+constexpr uint64_t get_parameter_tag(const_str s, unsigned p = 0) {
+  return p == s.size()
+             ? 0
+             : s[p] == '<'
+                   ? (is_int(s, p)
+                          ? get_parameter_tag(s, find_closing_tag(s, p)) * 6 + 1
+                          : is_uint(s, p)
+                                ? get_parameter_tag(s, find_closing_tag(s, p)) *
+                                          6 +
+                                      2
+                                : is_float(s, p)
+                                      ? get_parameter_tag(
+                                            s, find_closing_tag(s, p)) *
+                                                6 +
+                                            3
+                                      : is_str(s, p)
+                                            ? get_parameter_tag(
+                                                  s, find_closing_tag(s, p)) *
+                                                      6 +
+                                                  4
+                                            : is_path(s, p)
+                                                  ? get_parameter_tag(
+                                                        s, find_closing_tag(
+                                                               s, p)) *
+                                                            6 +
+                                                        5
+                                                  : throw std::runtime_error(
+                                                        "invalid parameter "
+                                                        "type"))
+                   : get_parameter_tag(s, p + 1);
+}
+#endif
+
+template <typename... T>
+struct S {
+  template <typename U>
+  using push = S<U, T...>;
+  template <typename U>
+  using push_back = S<T..., U>;
+  template <template <typename... Args> class U>
+  using rebind = U<T...>;
+};
+template <typename F, typename Set>
+struct CallHelper;
+template <typename F, typename... Args>
+struct CallHelper<F, S<Args...>> {
+  template <typename F1, typename... Args1,
+            typename = decltype(std::declval<F1>()(std::declval<Args1>()...))>
+  static char __test(int);
+
+  template <typename...>
+  static int __test(...);
+
+  static constexpr bool value = sizeof(__test<F, Args...>(0)) == sizeof(char);
+};
+
+template <int N>
+struct single_tag_to_type {};
+
+template <>
+struct single_tag_to_type<1> {
+  using type = int64_t;
+};
+
+template <>
+struct single_tag_to_type<2> {
+  using type = uint64_t;
+};
+
+template <>
+struct single_tag_to_type<3> {
+  using type = double;
+};
+
+template <>
+struct single_tag_to_type<4> {
+  using type = std::string;
+};
+
+template <>
+struct single_tag_to_type<5> {
+  using type = std::string;
+};
+
+template <uint64_t Tag>
+struct arguments {
+  using subarguments = typename arguments<Tag / 6>::type;
+  using type = typename subarguments::template push<
+      typename single_tag_to_type<Tag % 6>::type>;
+};
+
+template <>
+struct arguments<0> {
+  using type = S<>;
+};
+
+template <typename... T>
+struct last_element_type {
+  using type =
+      typename std::tuple_element<sizeof...(T)-1, std::tuple<T...>>::type;
+};
+
+template <>
+struct last_element_type<> {};
+
+// from
+// http://stackoverflow.com/questions/13072359/c11-compile-time-array-with-logarithmic-evaluation-depth
+template <class T>
+using Invoke = typename T::type;
+
+template <unsigned...>
+struct seq {
+  using type = seq;
+};
+
+template <class S1, class S2>
+struct concat;
+
+template <unsigned... I1, unsigned... I2>
+struct concat<seq<I1...>, seq<I2...>> : seq<I1..., (sizeof...(I1) + I2)...> {};
+
+template <class S1, class S2>
+using Concat = Invoke<concat<S1, S2>>;
+
+template <unsigned N>
+struct gen_seq;
+template <unsigned N>
+using GenSeq = Invoke<gen_seq<N>>;
+
+template <unsigned N>
+struct gen_seq : Concat<GenSeq<N / 2>, GenSeq<N - N / 2>> {};
+
+template <>
+struct gen_seq<0> : seq<> {};
+template <>
+struct gen_seq<1> : seq<0> {};
+
+template <typename Seq, typename Tuple>
+struct pop_back_helper;
+
+template <unsigned... N, typename Tuple>
+struct pop_back_helper<seq<N...>, Tuple> {
+  template <template <typename... Args> class U>
+  using rebind = U<typename std::tuple_element<N, Tuple>::type...>;
+};
+
+template <typename... T>
+struct pop_back  //: public pop_back_helper<typename
+                 //gen_seq<sizeof...(T)-1>::type, std::tuple<T...>>
+{
+  template <template <typename... Args> class U>
+  using rebind =
+      typename pop_back_helper<typename gen_seq<sizeof...(T)-1>::type,
+                               std::tuple<T...>>::template rebind<U>;
+};
+
+template <>
+struct pop_back<> {
+  template <template <typename... Args> class U>
+  using rebind = U<>;
+};
+
+// from
+// http://stackoverflow.com/questions/2118541/check-if-c0x-parameter-pack-contains-a-type
+template <typename Tp, typename... List>
+struct contains : std::true_type {};
+
+template <typename Tp, typename Head, typename... Rest>
+struct contains<Tp, Head, Rest...>
+    : std::conditional<std::is_same<Tp, Head>::value, std::true_type,
+                       contains<Tp, Rest...>>::type {};
+
+template <typename Tp>
+struct contains<Tp> : std::false_type {};
+
+template <typename T>
+struct empty_context {};
+
+template <typename T>
+struct promote {
+  using type = T;
+};
+
+#define CROW_INTERNAL_PROMOTE_TYPE(t1, t2) \
+  template <>                              \
+  struct promote<t1> {                     \
+    using type = t2;                       \
+  }
+
+CROW_INTERNAL_PROMOTE_TYPE(char, int64_t);
+CROW_INTERNAL_PROMOTE_TYPE(short, int64_t);
+CROW_INTERNAL_PROMOTE_TYPE(int, int64_t);
+CROW_INTERNAL_PROMOTE_TYPE(long, int64_t);
+CROW_INTERNAL_PROMOTE_TYPE(long long, int64_t);
+CROW_INTERNAL_PROMOTE_TYPE(unsigned char, uint64_t);
+CROW_INTERNAL_PROMOTE_TYPE(unsigned short, uint64_t);
+CROW_INTERNAL_PROMOTE_TYPE(unsigned int, uint64_t);
+CROW_INTERNAL_PROMOTE_TYPE(unsigned long, uint64_t);
+CROW_INTERNAL_PROMOTE_TYPE(unsigned long long, uint64_t);
+CROW_INTERNAL_PROMOTE_TYPE(float, double);
+#undef CROW_INTERNAL_PROMOTE_TYPE
+
+template <typename T>
+using promote_t = typename promote<T>::type;
+
+}  // namespace black_magic
+
+namespace detail {
+
+template <class T, std::size_t N, class... Args>
+struct get_index_of_element_from_tuple_by_type_impl {
+  static constexpr auto value = N;
+};
+
+template <class T, std::size_t N, class... Args>
+struct get_index_of_element_from_tuple_by_type_impl<T, N, T, Args...> {
+  static constexpr auto value = N;
+};
+
+template <class T, std::size_t N, class U, class... Args>
+struct get_index_of_element_from_tuple_by_type_impl<T, N, U, Args...> {
+  static constexpr auto value =
+      get_index_of_element_from_tuple_by_type_impl<T, N + 1, Args...>::value;
+};
+
+}  // namespace detail
+
+namespace utility {
+template <class T, class... Args>
+T& get_element_by_type(std::tuple<Args...>& t) {
+  return std::get<detail::get_index_of_element_from_tuple_by_type_impl<
+      T, 0, Args...>::value>(t);
+}
+
+template <typename T>
+struct function_traits;
+
+#ifndef CROW_MSVC_WORKAROUND
+template <typename T>
+struct function_traits : public function_traits<decltype(&T::operator())> {
+  using parent_t = function_traits<decltype(&T::operator())>;
+  static const size_t arity = parent_t::arity;
+  using result_type = typename parent_t::result_type;
+  template <size_t i>
+  using arg = typename parent_t::template arg<i>;
+};
+#endif
+
+template <typename ClassType, typename R, typename... Args>
+struct function_traits<R (ClassType::*)(Args...) const> {
+  static const size_t arity = sizeof...(Args);
+
+  typedef R result_type;
+
+  template <size_t i>
+  using arg = typename std::tuple_element<i, std::tuple<Args...>>::type;
+};
+
+template <typename ClassType, typename R, typename... Args>
+struct function_traits<R (ClassType::*)(Args...)> {
+  static const size_t arity = sizeof...(Args);
+
+  typedef R result_type;
+
+  template <size_t i>
+  using arg = typename std::tuple_element<i, std::tuple<Args...>>::type;
+};
+
+template <typename R, typename... Args>
+struct function_traits<std::function<R(Args...)>> {
+  static const size_t arity = sizeof...(Args);
+
+  typedef R result_type;
+
+  template <size_t i>
+  using arg = typename std::tuple_element<i, std::tuple<Args...>>::type;
+};
+
+inline static std::string base64encode(
+    const char* data, size_t size,
+    const char* key =
+        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/") {
+  std::string ret;
+  ret.resize((size + 2) / 3 * 4);
+  auto it = ret.begin();
+  while (size >= 3) {
+    *it++ = key[(((unsigned char)*data) & 0xFC) >> 2];
+    unsigned char h = (((unsigned char)*data++) & 0x03) << 4;
+    *it++ = key[h | ((((unsigned char)*data) & 0xF0) >> 4)];
+    h = (((unsigned char)*data++) & 0x0F) << 2;
+    *it++ = key[h | ((((unsigned char)*data) & 0xC0) >> 6)];
+    *it++ = key[((unsigned char)*data++) & 0x3F];
+
+    size -= 3;
+  }
+  if (size == 1) {
+    *it++ = key[(((unsigned char)*data) & 0xFC) >> 2];
+    unsigned char h = (((unsigned char)*data++) & 0x03) << 4;
+    *it++ = key[h];
+    *it++ = '=';
+    *it++ = '=';
+  } else if (size == 2) {
+    *it++ = key[(((unsigned char)*data) & 0xFC) >> 2];
+    unsigned char h = (((unsigned char)*data++) & 0x03) << 4;
+    *it++ = key[h | ((((unsigned char)*data) & 0xF0) >> 4)];
+    h = (((unsigned char)*data++) & 0x0F) << 2;
+    *it++ = key[h];
+    *it++ = '=';
+  }
+  return ret;
+}
+
+inline static std::string base64encode_urlsafe(const char* data, size_t size) {
+  return base64encode(
+      data, size,
+      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_");
+}
+
+}  // namespace utility
+}
diff --git a/crow/include/crow/websocket.h b/crow/include/crow/websocket.h
new file mode 100644
index 0000000..ac22d67
--- /dev/null
+++ b/crow/include/crow/websocket.h
@@ -0,0 +1,423 @@
+#pragma once
+#include <boost/algorithm/string/predicate.hpp>
+#include "crow/TinySHA1.hpp"
+#include "crow/http_request.h"
+#include "crow/socket_adaptors.h"
+
+namespace crow {
+namespace websocket {
+enum class WebSocketReadState {
+  MiniHeader,
+  Len16,
+  Len64,
+  Mask,
+  Payload,
+};
+
+struct connection {
+  virtual void send_binary(const std::string& msg) = 0;
+  virtual void send_text(const std::string& msg) = 0;
+  virtual void close(const std::string& msg = "quit") = 0;
+  virtual ~connection() {}
+
+  void userdata(void* u) { userdata_ = u; }
+  void* userdata() { return userdata_; }
+
+ private:
+  void* userdata_;
+};
+
+template <typename Adaptor>
+class Connection : public connection {
+ public:
+  Connection(
+      const crow::request& req, Adaptor&& adaptor,
+      std::function<void(crow::websocket::connection&)> open_handler,
+      std::function<void(crow::websocket::connection&, const std::string&,
+                         bool)>
+          message_handler,
+      std::function<void(crow::websocket::connection&, const std::string&)>
+          close_handler,
+      std::function<void(crow::websocket::connection&)> error_handler)
+      : adaptor_(std::move(adaptor)),
+        open_handler_(std::move(open_handler)),
+        message_handler_(std::move(message_handler)),
+        close_handler_(std::move(close_handler)),
+        error_handler_(std::move(error_handler)) {
+    if (!boost::iequals(req.get_header_value("upgrade"), "websocket")) {
+      adaptor.close();
+      delete this;
+      return;
+    }
+    // Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==
+    // Sec-WebSocket-Version: 13
+    std::string magic = req.get_header_value("Sec-WebSocket-Key") +
+                        "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
+    sha1::SHA1 s;
+    s.processBytes(magic.data(), magic.size());
+    uint8_t digest[20];
+    s.getDigestBytes(digest);
+    start(crow::utility::base64encode((char*)digest, 20));
+  }
+
+  template <typename CompletionHandler>
+  void dispatch(CompletionHandler handler) {
+    adaptor_.get_io_service().dispatch(handler);
+  }
+
+  template <typename CompletionHandler>
+  void post(CompletionHandler handler) {
+    adaptor_.get_io_service().post(handler);
+  }
+
+  void send_pong(const std::string& msg) {
+    dispatch([this, msg] {
+      char buf[3] = "\x8A\x00";
+      buf[1] += msg.size();
+      write_buffers_.emplace_back(buf, buf + 2);
+      write_buffers_.emplace_back(msg);
+      do_write();
+    });
+  }
+
+  void send_binary(const std::string& msg) override {
+    dispatch([this, msg] {
+      auto header = build_header(2, msg.size());
+      write_buffers_.emplace_back(std::move(header));
+      write_buffers_.emplace_back(msg);
+      do_write();
+    });
+  }
+
+  void send_text(const std::string& msg) override {
+    dispatch([this, msg] {
+      auto header = build_header(1, msg.size());
+      write_buffers_.emplace_back(std::move(header));
+      write_buffers_.emplace_back(msg);
+      do_write();
+    });
+  }
+
+  void close(const std::string& msg) override {
+    dispatch([this, msg] {
+      has_sent_close_ = true;
+      if (has_recv_close_ && !is_close_handler_called_) {
+        is_close_handler_called_ = true;
+        if (close_handler_) close_handler_(*this, msg);
+      }
+      auto header = build_header(0x8, msg.size());
+      write_buffers_.emplace_back(std::move(header));
+      write_buffers_.emplace_back(msg);
+      do_write();
+    });
+  }
+
+ protected:
+  std::string build_header(int opcode, size_t size) {
+    char buf[2 + 8] = "\x80\x00";
+    buf[0] += opcode;
+    if (size < 126) {
+      buf[1] += size;
+      return {buf, buf + 2};
+    } else if (size < 0x10000) {
+      buf[1] += 126;
+      *(uint16_t*)(buf + 2) = htons((uint16_t)size);
+      return {buf, buf + 4};
+    } else {
+      buf[1] += 127;
+      *(uint64_t*)(buf + 2) =
+          ((1 == htonl(1)) ? (uint64_t)size
+                           : ((uint64_t)htonl((size)&0xFFFFFFFF) << 32) |
+                                 htonl((size) >> 32));
+      return {buf, buf + 10};
+    }
+  }
+
+  void start(std::string&& hello) {
+    static std::string header =
+        "HTTP/1.1 101 Switching Protocols\r\n"
+        "Upgrade: websocket\r\n"
+        "Connection: Upgrade\r\n"
+        "Sec-WebSocket-Protocol: binary\n"  // TODO(ed): this hardcodes binary.
+                                            // find a better way
+        "Sec-WebSocket-Accept: ";
+    static std::string crlf = "\r\n";
+    write_buffers_.emplace_back(header);
+    write_buffers_.emplace_back(std::move(hello));
+    write_buffers_.emplace_back(crlf);
+    write_buffers_.emplace_back(crlf);
+    do_write();
+    if (open_handler_) open_handler_(*this);
+    do_read();
+  }
+
+  void do_read() {
+    is_reading = true;
+    switch (state_) {
+      case WebSocketReadState::MiniHeader: {
+        // boost::asio::async_read(adaptor_.socket(),
+        // boost::asio::buffer(&mini_header_, 1),
+        adaptor_.socket().async_read_some(
+            boost::asio::buffer(&mini_header_, 2),
+            [this](const boost::system::error_code& ec,
+                   std::size_t bytes_transferred) {
+              is_reading = false;
+              mini_header_ = htons(mini_header_);
+#ifdef CROW_ENABLE_DEBUG
+
+              if (!ec && bytes_transferred != 2) {
+                throw std::runtime_error(
+                    "WebSocket:MiniHeader:async_read fail:asio bug?");
+              }
+#endif
+
+              if (!ec && ((mini_header_ & 0x80) == 0x80)) {
+                if ((mini_header_ & 0x7f) == 127) {
+                  state_ = WebSocketReadState::Len64;
+                } else if ((mini_header_ & 0x7f) == 126) {
+                  state_ = WebSocketReadState::Len16;
+                } else {
+                  remaining_length_ = mini_header_ & 0x7f;
+                  state_ = WebSocketReadState::Mask;
+                }
+                do_read();
+              } else {
+                close_connection_ = true;
+                adaptor_.close();
+                if (error_handler_) error_handler_(*this);
+                check_destroy();
+              }
+            });
+      } break;
+      case WebSocketReadState::Len16: {
+        remaining_length_ = 0;
+        boost::asio::async_read(
+            adaptor_.socket(), boost::asio::buffer(&remaining_length_, 2),
+            [this](const boost::system::error_code& ec,
+                   std::size_t bytes_transferred) {
+              is_reading = false;
+              remaining_length_ = ntohs(*(uint16_t*)&remaining_length_);
+#ifdef CROW_ENABLE_DEBUG
+              if (!ec && bytes_transferred != 2) {
+                throw std::runtime_error(
+                    "WebSocket:Len16:async_read fail:asio bug?");
+              }
+#endif
+
+              if (!ec) {
+                state_ = WebSocketReadState::Mask;
+                do_read();
+              } else {
+                close_connection_ = true;
+                adaptor_.close();
+                if (error_handler_) error_handler_(*this);
+                check_destroy();
+              }
+            });
+      } break;
+      case WebSocketReadState::Len64: {
+        boost::asio::async_read(
+            adaptor_.socket(), boost::asio::buffer(&remaining_length_, 8),
+            [this](const boost::system::error_code& ec,
+                   std::size_t bytes_transferred) {
+              is_reading = false;
+              remaining_length_ =
+                  ((1 == ntohl(1))
+                       ? (remaining_length_)
+                       : ((uint64_t)ntohl((remaining_length_)&0xFFFFFFFF)
+                          << 32) |
+                             ntohl((remaining_length_) >> 32));
+#ifdef CROW_ENABLE_DEBUG
+              if (!ec && bytes_transferred != 8) {
+                throw std::runtime_error(
+                    "WebSocket:Len16:async_read fail:asio bug?");
+              }
+#endif
+
+              if (!ec) {
+                state_ = WebSocketReadState::Mask;
+                do_read();
+              } else {
+                close_connection_ = true;
+                adaptor_.close();
+                if (error_handler_) error_handler_(*this);
+                check_destroy();
+              }
+            });
+      } break;
+      case WebSocketReadState::Mask:
+        boost::asio::async_read(
+            adaptor_.socket(), boost::asio::buffer((char*)&mask_, 4),
+            [this](const boost::system::error_code& ec,
+                   std::size_t bytes_transferred) {
+              is_reading = false;
+#ifdef CROW_ENABLE_DEBUG
+              if (!ec && bytes_transferred != 4) {
+                throw std::runtime_error(
+                    "WebSocket:Mask:async_read fail:asio bug?");
+              }
+#endif
+
+              if (!ec) {
+                state_ = WebSocketReadState::Payload;
+                do_read();
+              } else {
+                close_connection_ = true;
+                if (error_handler_) error_handler_(*this);
+                adaptor_.close();
+              }
+            });
+        break;
+      case WebSocketReadState::Payload: {
+        size_t to_read = buffer_.size();
+        if (remaining_length_ < to_read) to_read = remaining_length_;
+        adaptor_.socket().async_read_some(
+            boost::asio::buffer(buffer_, to_read),
+            [this](const boost::system::error_code& ec,
+                   std::size_t bytes_transferred) {
+              is_reading = false;
+
+              if (!ec) {
+                fragment_.insert(fragment_.end(), buffer_.begin(),
+                                 buffer_.begin() + bytes_transferred);
+                remaining_length_ -= bytes_transferred;
+                if (remaining_length_ == 0) {
+                  handle_fragment();
+                  state_ = WebSocketReadState::MiniHeader;
+                  do_read();
+                }
+              } else {
+                close_connection_ = true;
+                if (error_handler_) error_handler_(*this);
+                adaptor_.close();
+              }
+            });
+      } break;
+    }
+  }
+
+  bool is_FIN() { return mini_header_ & 0x8000; }
+
+  int opcode() { return (mini_header_ & 0x0f00) >> 8; }
+
+  void handle_fragment() {
+    for (decltype(fragment_.length()) i = 0; i < fragment_.length(); i++) {
+      fragment_[i] ^= ((char*)&mask_)[i % 4];
+    }
+    switch (opcode()) {
+      case 0:  // Continuation
+      {
+        message_ += fragment_;
+        if (is_FIN()) {
+          if (message_handler_) message_handler_(*this, message_, is_binary_);
+          message_.clear();
+        }
+      }
+      case 1:  // Text
+      {
+        is_binary_ = false;
+        message_ += fragment_;
+        if (is_FIN()) {
+          if (message_handler_) message_handler_(*this, message_, is_binary_);
+          message_.clear();
+        }
+      } break;
+      case 2:  // Binary
+      {
+        is_binary_ = true;
+        message_ += fragment_;
+        if (is_FIN()) {
+          if (message_handler_) message_handler_(*this, message_, is_binary_);
+          message_.clear();
+        }
+      } break;
+      case 0x8:  // Close
+      {
+        has_recv_close_ = true;
+        if (!has_sent_close_) {
+          close(fragment_);
+        } else {
+          adaptor_.close();
+          close_connection_ = true;
+          if (!is_close_handler_called_) {
+            if (close_handler_) close_handler_(*this, fragment_);
+            is_close_handler_called_ = true;
+          }
+          check_destroy();
+        }
+      } break;
+      case 0x9:  // Ping
+      {
+        send_pong(fragment_);
+      } break;
+      case 0xA:  // Pong
+      {
+        pong_received_ = true;
+      } break;
+    }
+
+    fragment_.clear();
+  }
+
+  void do_write() {
+    if (sending_buffers_.empty()) {
+      sending_buffers_.swap(write_buffers_);
+      std::vector<boost::asio::const_buffer> buffers;
+      buffers.reserve(sending_buffers_.size());
+      for (auto& s : sending_buffers_) {
+        buffers.emplace_back(boost::asio::buffer(s));
+      }
+      boost::asio::async_write(adaptor_.socket(), buffers,
+                               [&](const boost::system::error_code& ec,
+                                   std::size_t /*bytes_transferred*/) {
+                                 sending_buffers_.clear();
+                                 if (!ec && !close_connection_) {
+                                   if (!write_buffers_.empty()) do_write();
+                                   if (has_sent_close_)
+                                     close_connection_ = true;
+                                 } else {
+                                   close_connection_ = true;
+                                   check_destroy();
+                                 }
+                               });
+    }
+  }
+
+  void check_destroy() {
+    // if (has_sent_close_ && has_recv_close_)
+    if (!is_close_handler_called_)
+      if (close_handler_) close_handler_(*this, "uncleanly");
+    if (sending_buffers_.empty() && !is_reading) delete this;
+  }
+
+ private:
+  Adaptor adaptor_;
+
+  std::vector<std::string> sending_buffers_;
+  std::vector<std::string> write_buffers_;
+
+  boost::array<char, 4096> buffer_;
+  bool is_binary_;
+  std::string message_;
+  std::string fragment_;
+  WebSocketReadState state_{WebSocketReadState::MiniHeader};
+  uint64_t remaining_length_{0};
+  bool close_connection_{false};
+  bool is_reading{false};
+  uint32_t mask_;
+  uint16_t mini_header_;
+  bool has_sent_close_{false};
+  bool has_recv_close_{false};
+  bool error_occured_{false};
+  bool pong_received_{false};
+  bool is_close_handler_called_{false};
+
+  std::function<void(crow::websocket::connection&)> open_handler_;
+  std::function<void(crow::websocket::connection&, const std::string&, bool)>
+      message_handler_;
+  std::function<void(crow::websocket::connection&, const std::string&)>
+      close_handler_;
+  std::function<void(crow::websocket::connection&)> error_handler_;
+};
+}
+}