言修 — kotoshu

The name joins two characters. Koto (言) is word, speech, language. Shu (修) is to fix, to mend, to cultivate — as one cultivates a garden or refines a craft. Together: the fixing or embellishing of words.

The name quietly echoes two older compounds: 修辞 (shūji, rhetoric — the ornamenting of words) and 修養 (shūyō, self-cultivation). Spell checking, done well, is both: a small act of rhetoric applied with care, and a daily discipline of refinement.

The mark

The mark is a sprouting leaf rendered in six tones. Words, tended, grow — the checker is the gardener. The muted sage variant lives on light ground; the vivid green-and-gold variant, on ink. Both share one geometry, as light and dark share one site.

Brand assets — both SVGs, high-resolution PNGs, and the source PDF — are in the repository under assets/.

The architecture

Kotoshu is a small constellation of repositories. The checking engine has two native implementations that must stay byte-identical — a Ruby gem and a Rust core, both reimplementing the Hunspell algorithms with pluggable suggestion strategies and an optional semantic layer, pinned together by a frozen conformance contract that CI enforces on every change. Around the engines sit thin adapters — a wasm build, an LSP server, an HTTP API, SDKs, a GitHub Action, a Docker image — and three content repos (dictionaries, frequency lists, ONNX models) fetched on demand, never vendored.

See the projects page for the full map.

Stewardship

Kotoshu is developed in the open by Ribose Inc. and contributors, under the BSD-2-Clause license — the same terms as the core gem. Issues, dictionary contributions, and language modules are welcome in each repository.