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+# μpb (this repo is no longer supported)
 **As of August 25, 2023, μpb has moved into the protobuf repo
 [here](https://github.com/protocolbuffers/protobuf/tree/main/upb). All further
 development is happening there, and this repo is no longer being updated.**
-
-# μpb: small, fast C protos
-
-μpb (often written 'upb') is a small
-[protobuf](https://github.com/protocolbuffers/protobuf) implementation written
-in C.
-
-upb is the core runtime for protobuf languages extensions in
-[Ruby](https://github.com/protocolbuffers/protobuf/tree/master/ruby),
-[PHP](https://github.com/protocolbuffers/protobuf/tree/master/php), and
-[Python](https://github.com/protocolbuffers/upb/tree/main/python).
-
-While upb offers a C API, the C API & ABI **are not stable**. For this reason,
-upb is not generally offered as a C library for direct consumption, and there
-are no releases.
-
-## Features
-
-upb has comparable speed to protobuf C++, but is an order of magnitude smaller
-in code size.
-
-Like the main protobuf implementation in C++, it supports:
-
-- a generated API (in C)
-- reflection
-- binary & JSON wire formats
-- text format serialization
-- all standard features of protobufs (oneofs, maps, unknown fields, extensions,
-  etc.)
-- full conformance with the protobuf conformance tests
-
-upb also supports some features that C++ does not:
-
-- **optional reflection:** generated messages are agnostic to whether
-  reflection will be linked in or not.
-- **no global state:** no pre-main registration or other global state.
-- **fast reflection-based parsing:** messages loaded at runtime parse
-  just as fast as compiled-in messages.
-
-However there are a few features it does not support:
-
-- text format parsing
-- deep descriptor verification: upb's descriptor validation is not as exhaustive
-  as `protoc`.
-
-## Install
-
-For Ruby, use [RubyGems](https://rubygems.org/gems/google-protobuf):
-
-```
-$ gem install google-protobuf
-```
-
-For PHP, use [PECL](https://pecl.php.net/package/protobuf):
-
-```
-$ sudo pecl install protobuf
-```
-
-For Python, use [PyPI](https://pypi.org/project/protobuf/):
-
-```
-$ sudo pip install protobuf
-```
-
-Alternatively, you can build and install upb using
-[vcpkg](https://github.com/microsoft/vcpkg/) dependency manager:
-
-    git clone https://github.com/Microsoft/vcpkg.git
-    cd vcpkg
-    ./bootstrap-vcpkg.sh
-    ./vcpkg integrate install
-    ./vcpkg install upb
-
-The upb port in vcpkg is kept up to date by microsoft team members and community
-contributors.
-
-If the version is out of date, please
-[create an issue or pull request](https://github.com/Microsoft/vcpkg) on the
-vcpkg repository.
-
-## Contributing
-
-Please see [CONTRIBUTING.md](CONTRIBUTING.md).