GHC is the compiler for Haskell. The Glorious Glasgow Haskell Compilation System is a marvel of open source software engineering.
Based on the lambda calculus/type system of System F\(_c\) GHC has been, and remains, the leading (Haskell) compiler for PLT research for several decades. It also has a small but high-powered commercial and industrial community that produce a range of unique and world leading products using GHC as the primary development platform.
It has GHC spawned many forks and fostered the development of several state of the art new languages.
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