OpenTypeSolut

OpenTypeSolut, abbreviated opentypesolut, is an open-source software project that provides a solver framework for testing and applying OpenType typography features. It targets font developers, typesetters, and researchers who need to understand how OpenType GSUB (glyph substitution) and GPOS (glyph positioning) features affect glyph sequences, substitutions, and layout across complex scripts.

Originating as a community project in the early 2020s, opentypesolut was designed to be language-agnostic, modular, and extensible. It is hosted on public version control platforms with contributions from typographers, engineers, and linguists.

Core capabilities include a feature parser, a shaping simulator that applies GSUB and GPOS rules, and a test environment for rendering results. It supports common features, contextual substitutions, ligatures, kerning, and positioning for multiple scripts.

Architecturally, opentypesolut uses a pluggable core engine and language bindings to integrate with typography pipelines. It targets cross-platform releases compatible with font-editing workflows.

Typical use cases include validating feature behavior during font development, debugging complex scripts, and generating reproducible test cases for feature interactions.

Licensing is open-source under a permissive license, with governance by the community. Users report utility for technical verification, though beginners may face a learning curve.

See also: OpenType, GSUB, GPOS, fontTools, typography software.