A Haskell implementation of MessagePack

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LTS Haskell 14.27:
Stackage Nightly 2019-09-21:
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BSD-3-Clause licensed by Hideyuki Tanaka
This version can be pinned in stack with:msgpack-,2990

A Haskell implementation of the MessagePack data interchange format. MessagePack is a binary format which aims to be compact and supports encoding a superset of the JSON data-model.

Related Packages

A JSON adapter for the aeson library is provided by the msgpack-aeson package.

The msgpack-rpc package provides an implementation of the MessagePack-RPC protocol.


  • Fix incorrect MessagePack tag when encoding single-precision Floats
  • Fix looping/hanging MessagePack (Maybe a) instance
  • Add support for binary-0.8 API
  • Drop dependency on blaze-builder
  • Add new operations
    • getWord, getWord64, getInt64
    • putWord, putWord64, putInt64
  • Add Read instance for Object and Assoc
  • Add Generic instance for Object
  • Add Object instance ShortByteString
  • Declare API Trustworthy for SafeHaskell