The compiler comes as a command line utility, with options similar to those of csc.exe, and as an MSBuild task (and a corresponding .targets file).
To get started compiling, see the Getting Started guide.
The compiler supports most of C# 5.0. For details, see Language Fetaures.
There are samples available at https://github.com/erik-kallen/SaltarelleCompilerSamples.
There is a forum for users: http://saltarellecompiler.freeforums.org/
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