diff --git a/pid/builderconfig.cpp b/pid/builderconfig.cpp
new file mode 100644
index 0000000..33301e2
--- /dev/null
+++ b/pid/builderconfig.cpp
@@ -0,0 +1,153 @@
+/**
+ * Copyright 2017 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "pid/builderconfig.hpp"
+
+#include <fstream>
+#include <iostream>
+#include <libconfig.h++>
+#include <memory>
+#include <sdbusplus/bus.hpp>
+#include <string>
+#include <unordered_map>
+
+#include "conf.hpp"
+#include "pid/builder.hpp"
+
+std::unordered_map<int64_t, std::unique_ptr<PIDZone>> BuildZonesFromConfig(
+        const std::string& path,
+        SensorManager& mgr,
+        sdbusplus::bus::bus& modeControlBus)
+{
+    using namespace libconfig;
+    // zone -> pids
+    std::map<int64_t, PIDConf> pidConfig;
+    // zone -> configs
+    std::map<int64_t, struct zone> zoneConfig;
+
+    std::cerr << "entered BuildZonesFromConfig\n";
+
+    Config cfg;
+
+    /* The load was modeled after the example source provided. */
+    try
+    {
+        cfg.readFile(path.c_str());
+    }
+    catch (const FileIOException& fioex)
+    {
+        std::cerr << "I/O error while reading file: " << fioex.what()
+                  << std::endl;
+        throw;
+    }
+    catch (const ParseException& pex)
+    {
+        std::cerr << "Parse error at " << pex.getFile() << ":" << pex.getLine()
+                  << " - " << pex.getError() << std::endl;
+        throw;
+    }
+
+    try
+    {
+        const Setting& root = cfg.getRoot();
+        const Setting& zones = root["zones"];
+        int count = zones.getLength();
+
+        /* For each zone. */
+        for (int i = 0; i < count; ++i)
+        {
+            const Setting& zoneSettings = zones[i];
+
+            int id;
+            PIDConf thisZone;
+            struct zone thisZoneConfig;
+
+            zoneSettings.lookupValue("id", id);
+
+            thisZoneConfig.minthermalrpm =
+                    zoneSettings.lookup("minthermalrpm");
+            thisZoneConfig.failsafepercent =
+                    zoneSettings.lookup("failsafepercent");
+
+            const Setting& pids = zoneSettings["pids"];
+            int pidCount = pids.getLength();
+
+            for (int j = 0; j < pidCount; ++j)
+            {
+                const Setting& pid = pids[j];
+
+                std::string name;
+                controller_info info;
+
+                /*
+                 * Mysteriously if you use lookupValue on these, and the type
+                 * is float.  It won't work right.
+                 *
+                 * If the configuration file value doesn't look explicitly like
+                 * a float it won't let you assign it to one.
+                 */
+                name = pid.lookup("name").c_str();
+                info.type = pid.lookup("type").c_str();
+                /* set-point is only required to be set for thermal. */
+                /* TODO(venture): Verify this works optionally here. */
+                info.setpoint = pid.lookup("set-point");
+                info.info.ts = pid.lookup("pid.sampleperiod");
+                info.info.p_c = pid.lookup("pid.p_coefficient");
+                info.info.i_c = pid.lookup("pid.i_coefficient");
+                info.info.ff_off = pid.lookup("pid.ff_off_coefficient");
+                info.info.ff_gain = pid.lookup("pid.ff_gain_coefficient");
+                info.info.i_lim.min = pid.lookup("pid.i_limit.min");
+                info.info.i_lim.max = pid.lookup("pid.i_limit.max");
+                info.info.out_lim.min = pid.lookup("pid.out_limit.min");
+                info.info.out_lim.max = pid.lookup("pid.out_limit.max");
+                info.info.slew_neg = pid.lookup("pid.slew_neg");
+                info.info.slew_pos = pid.lookup("pid.slew_pos");
+
+                std::cerr << "out_lim.min: " << info.info.out_lim.min << "\n";
+                std::cerr << "out_lim.max: " << info.info.out_lim.max << "\n";
+
+                const Setting& inputs = pid["inputs"];
+                int icount = inputs.getLength();
+
+                for (int z = 0; z < icount; ++z)
+                {
+                    std::string v;
+                    v = pid["inputs"][z].c_str();
+                    info.inputs.push_back(v);
+                }
+
+                thisZone[name] = info;
+            }
+
+            pidConfig[static_cast<int64_t>(id)] = thisZone;
+            zoneConfig[static_cast<int64_t>(id)] = thisZoneConfig;
+        }
+    }
+    catch (const SettingTypeException &setex)
+    {
+        std::cerr << "Setting '" << setex.getPath() << "' type exception!"
+                  << std::endl;
+        throw;
+    }
+    catch (const SettingNotFoundException& snex)
+    {
+        std::cerr << "Setting '" << snex.getPath() << "' not found!"
+                  << std::endl;
+        throw;
+    }
+
+    return BuildZones(pidConfig, zoneConfig, mgr, modeControlBus);
+}