# \[ANN\] MsgPack.jl v1.0.0

**URL:** <https://discourse.julialang.org/t/ann-msgpack-jl-v1-0-0/28575>\
**Category:** Package Announcements\
**Created:** [September 9, 2019, 7:40pm UTC](https://discourse.julialang.org/t/ann-msgpack-jl-v1-0-0/28575 "2019-09-09T19:40:33Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![jrevels](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jrevels/32/10393_2.png) [@jrevels](https://discourse.julialang.org/u/jrevels)\
**Post date:** [September 9, 2019, 7:40pm UTC](https://discourse.julialang.org/t/ann-msgpack-jl-v1-0-0/28575/1 "2019-09-09T19:40:33Z")

</div>

Hello!

I’m pleased to share that [MsgPack.jl](https://github.com/JuliaIO/MsgPack.jl/) will [soon be updated to v1.0.0](https://github.com/JuliaRegistries/General/pull/3402).

This major version bump brings a variety of features/improvements (many of which are inspired by @quinnj’s awesome [JSON3.jl](https://github.com/quinnj/JSON3.jl)!):

- overloadable pre-(de)serialization transformations (see `from_msgpack` and `to_msgpack`)
- automatic type construction/destruction (see `msgpack_type`, `ImmutableStructType`, and `MutableStructType`)
- some basic immutable “views” over MsgPack-formatted byte buffers (see `ArrayView`, `MapView`).

I’m sure there are still plenty of areas for performance improvements, avoiding dynamic dispatches, better string/symbol handling, etc. PRs and issues welcome!

While this is a major version bump due to drastic changes in the internals, I’ve tried to avoid actually breaking MsgPack’s existing API; please open an issue if you experience breakage.