This is a simplified flate compression algorithm based on Go's implementation: https://cs.opensource.google/go/go/+/refs/tags/go1.23.1:src/compress/flate/deflatefast.go which has the copyright notice:
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
The code has been updated to support compiler:
$ moon version --all
moon 0.1.20250918 (e5fa392 2025-09-18) ~/.moon/bin/moon
moonc v0.6.28+d96d14d39 (2025-09-18) ~/.moon/bin/moonc
moonrun 0.1.20250918 (e5fa392 2025-09-18) ~/.moon/bin/moonrun
moon-pilot 0.0.1-850379f (2025-09-19) ~/.moon/bin/moon-pilot