GeezerVison

👋 Moin! We are TypeFox – a small team of software pioneers in Kiel, northern Germany. We invent open source tools for language engineering, developer tooling, and domain-specific AI. And we put them to work: when clients bring us a problem, we find out what they actually need, architect the solution, and take ownership until it's solved. AI agents are part of that daily work – we know what they're good at, and where they still need us.

The open source projects we founded and actively maintain, sorted by what they help you build:

Languages and language tooling

• Langium – build domain-specific languages in TypeScript; the de-facto standard for DSLs on the web
• Lanzer – a semiformal language for modeling fixtures and testing langium-based DSLs through coding agents
• Typir – give your language a type system: inference, subtyping, assignability, validation
• Fastbelt – our newest framework: high-performance language tooling in Go, for responsive editing in large workspaces

Domain-specific AI

• Langium AI – ground LLMs in the syntax and semantics of your DSL
• Baukasten – React components for feature-rich tools in VS Code, Theia, and the web
• agent-skills – a collection of agent skills for state-of-the-art software engineering

IDEs and collaboration

• Theia – the platform for fully customized, web-native IDEs, desktop or cloud
• monaco-languageclient – bring language servers into Monaco-based web editors
• VS Code Messenger – type-safe messaging between VS Code extensions and webviews
• Open Collaboration Tools – real-time collaboration across IDEs and web apps

Diagrams

• Sprotty – interactive, web-native diagrams with automatic layout

Our GitHub organization is where new ideas take shape – have a look around, open an issue, send a PR. And if one of these tools sits close to a problem you're working on, we'd like to hear about it: typefox.io