PureCake: A Verified Compiler for a Lazy Functional Language

We present PureCake, a mechanically-verified compiler for PureLang, lazy, purely functional programming language with monadic effects. PureLang syntax is Haskell-like and indentation-sensitive, its constraint-based Hindley-Milner type system guarantees safe execution. derive sound equational reasoning principles over operational semantics, dramatically simplifying some proofs. prove end-to-end correctness the compilation of down to machine code---the first such result any lazy language---by targeting CakeML composing verified compiler. Multiple optimisation passes are necessary handle realistic idioms effectively. develop PureCake entirely within HOL4 interactive theorem prover.