Greetings Haskellers, I am writing to draw your attention to https://github.com/haskell/unix/pull/135. The unix library conditionally supports the common baud rate extensions 57600 and 115200. Modern POSIX systems support a much wider set of extensions, and this PR adds additional extended baud rates that have been available on MacOS and Linux for several years. The same CPP mechanism for conditionally enabling these extensions is used. The PR has been open for a few months and I am interested in moving it forward. Thanks for your time, Travis Whitaker