astui

astui is an open-source toolkit designed to visualize and interact with abstract syntax trees (ASTs) used in programming language tooling. It provides a collection of components, data models, and APIs that enable developers to render ASTs as interactive diagrams, edit nodes, and apply transformations. The project aims to make AST exploration accessible for educators, tool authors, and developers working on compilers, linters, or code editors.

Core features include an interactive tree viewer with pan and zoom, node editing and reparenting, search and filtering, and support for common AST formats such as ESTree along with adapters for custom representations. astui is designed to be framework-agnostic and embeddable in web applications, with optional integrations for popular front-end stacks to streamline adoption in existing projects.

Architecture and interoperability: astui uses a modular architecture that allows developers to plug in language parsers and mapping layers to a uniform internal representation. It supports exporting tree views to static images or JSON, and it provides hooks for extending rendering, interaction, and transformation behaviors. The toolkit emphasizes accessibility and keyboard navigation to ensure it is usable in educational and professional contexts.

Development and licensing: astui is maintained by an open-source community and released under a permissive license. Contributions include documentation, example integrations, and plug-ins that extend rendering, editing capabilities, or language adapters. The project is commonly adopted in academia for teaching AST concepts and in tooling workflows that require visual debugging of code transformations.

See also: Abstract syntax tree, Code visualization, AST tooling.