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A proof checker meant for education. Primarily for teaching proofs of correctness of functional programs.

Metamath-knife can rapidly verify Metamath proofs, providing strong confidence that the proofs are correct.

mmj2 GUI Proof Assistant for the Metamath project

Library implementing type inference/checking functionality based on the Lean theorem prover

VSCode Extension - Proof Assistant for Metamath

Type Theory

Partial function application macro for Rust

Introduction to parsing with Haskell and Parsec

ANSI terminal support for Haskell, with Windows compatibility

Layout data in grids and pretty tables. Provides a lot of tools to get the cell formatting right (positional alignment, alignment on specific characters and limiting of cell width)..

A purely functional programming language with first class types

GRIN is a compiler back-end for lazy and strict functional languages with whole program optimization support.

Command and Conquer: Generals - Zero Hour

A user-centric visual STG implementation to help understand GHC/Haskell's execution model.

Rewrite Rule Inference Using Equality Saturation

A purely functional E-Graph library

Spoofax runtime

A self-hosting Racket on RPython meta-tracing JIT back-end.

racket implementation of language etl

Expression transformation language. An esolang.

A collection of core libraries for Racket

Zero-copy string unescaping library for Rust

A basic lisp parsing library

IO-agnostic line editor for embedded systems