ByteString is a small utility library that provides an immutable byte string type with many convenient operations.
To build ByteString from source you will need an F# 3.1 compiler and .NET development environment. The .fsproj file in the source directory should be understood by command line tools like Microsoft's msbuild or Mono's xbuild as well as IDEs such as MonoDevelop or VisualStudio.
ByteString is a library. Basic usage may look like this:
#r "ByteString" open ByteString let b = ByteString.FromStringUTF8("Hello world!") printfn "Message digest: %s" <| b.GetHash("SHA-256").ToSpeak64()