Tools & SDKs

Ways to run Lemma, from embedding the engine in your app to driving it from the command line.

Lemma SDKs

Embed Lemma directly in your language:

• Rust
• Elixir
• JavaScript / TypeScript
• Java / Kotlin
• Python (coming soon)
• C# / .NET (coming soon)

More SDKs are on the way. Precompiled binaries make each new one straightforward to add.

Command line & servers

• Lemma CLI: lemma run, show, list, format, install, plus server, lsp, and mcp
• Lemma MCP: connect Claude, Gemini CLI, or Cursor to your specs over the Model Context Protocol
• Registry: LemmaBase: share and reuse specs via @owner/name imports on uses

Notes that apply to every SDK

• Same engine underneath, so results are identical across languages.
• load validates: invalid specs are rejected there, never at run time.
• The engine never hits the network. Resolve @... registry references before loading.
• Explanations are opt-in (explain: true / --explain). Wire shape: api.v1.json (RuleResult.explanation → RuleNode; nested tree under ExplanationNode).
• Java / Kotlin package requires JDK 21+.
• Editor support (any language): the VS Code / Cursor extension drives lemma lsp.