symspell.mbt is a pure MoonBit implementation of the Symmetric Delete algorithm.
Its dictionary and lookup behavior follows these MIT-licensed implementations:

Original C# SymSpell by Wolf Garbe:
https://github.com/wolfgarbe/SymSpell
Copyright (c) 2021 Wolf Garbe

Python symspellpy by mmb L:
https://github.com/mammothb/symspellpy
Copyright (c) 2025 mmb L
Reference release: 6.10.0
Source inspected at commit 3566f13f16284ebe613910191828dff43de4e2ba.

The upstream copyright notices and MIT license are preserved in LICENSE.
The checked-in compatibility fixtures are generated using symspellpy 6.10.0.
Phrase fixtures use synthetic dictionaries and canonical single-word tie order.
Segmentation whitespace fixes and explicit casing/normalization policy are
documented in README.mbt.md and covered by separate regression tests.
No upstream frequency dictionaries are bundled. Supply a dictionary suitable
for your application and follow its own license terms.

Corpus tokenization follows symspellpy's letter/number/apostrophe pattern,
with explicit casing and a pinned Unicode category version as documented.
corpus_unicode.mbt is derived from Unicode 16.0.0 UnicodeData.txt:
https://www.unicode.org/Public/16.0.0/ucd/UnicodeData.txt
Copyright © 1991-2026 Unicode, Inc. Distributed under Unicode License V3;
the complete notice is in UNICODE-LICENSE.txt.

The portable binary snapshot format is specific to this MoonBit library.
Its byte fixtures are generated independently with Python's standard library;
they do not use upstream serialization formats or bundled dictionaries.