diff --git a/include/fru_reader.hpp b/include/fru_reader.hpp
new file mode 100644
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--- /dev/null
+++ b/include/fru_reader.hpp
@@ -0,0 +1,62 @@
+/*
+// Copyright (c) 2022 Equinix, 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.
+*/
+
+#pragma once
+
+#include <cstdint>
+#include <functional>
+#include <map>
+#include <optional>
+#include <utility>
+
+extern "C"
+{
+// For I2C_SMBUS_BLOCK_MAX
+#include <linux/i2c.h>
+}
+
+// A function to read up to I2C_SMBUS_BLOCK_MAX bytes of FRU data.  Returns
+// negative on error, or the number of bytes read otherwise, which may be (but
+// is not guaranteed to be) less than len if the read would go beyond the end
+// of the FRU.
+using ReadBlockFunc =
+    std::function<int64_t(off_t offset, size_t len, uint8_t* outbuf)>;
+
+// A caching wrapper around a ReadBlockFunc
+class FRUReader
+{
+  public:
+    FRUReader(ReadBlockFunc readFunc) : readFunc(std::move(readFunc))
+    {}
+    // The ::read() operation here is analogous to ReadBlockFunc (with the same
+    // return value semantics), but is not subject to SMBus block size
+    // limitations; it can read as much data as needed in a single call.
+    ssize_t read(off_t start, size_t len, uint8_t* outbuf);
+
+  private:
+    static constexpr size_t cacheBlockSize = 32;
+    static_assert(cacheBlockSize <= I2C_SMBUS_BLOCK_MAX);
+    using CacheBlock = std::array<uint8_t, cacheBlockSize>;
+
+    // indexed by block number (byte number / block size)
+    using Cache = std::map<uint32_t, CacheBlock>;
+
+    ReadBlockFunc readFunc;
+    Cache cache;
+
+    // byte offset of the end of the FRU (if readFunc has reported it)
+    std::optional<size_t> eof;
+};