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Crow supports Zlib compression using Gzip or Deflate algorithms.

HTTP Compression

HTTP compression is by default disabled in crow. Do the following to enable it:
1. Add #define CROW_ENABLE_COMPRESSION to the top of your main source file. 2. Call use_compression(crow::compression::algorithm) on your crow app. 3. When compiling your application, make sure that ZLIB is included as a dependency. Either through -lz argument or find_package(ZLIB) in CMake.


step 3 is not needed for MSVC since vcpckg.json already includes zlib as a dependency by default

For the compression algorim you can use crow::compression::algorithm::DEFLATE or crow::compression::algorithm::GZIP.
And now your HTTP responses will be compressed.

Websocket Compression

Crow currently does not support Websocket compression.
Feel free to discuss the subject with us on Github if you're feeling adventurous and want to try to implement it. We appreciate all the help.