Installation

Lemma is designed to run wherever your rules need to live. Install the CLI to evaluate specs from the terminal, embed the engine directly in Rust, JavaScript/TypeScript, Elixir, or Java/Kotlin via Maven, serve specs over HTTP or MCP, or pull a Docker image for containerized workloads. For language bindings and the full SDK documentation, see Tools & SDKs.

Lemma CLI

From crates.io/crates/lemma:

cargo install lemma

Or via npm:

npm install -g lemma

See Lemma CLI for all commands.

Embed Lemma in your application

Lemma can be embedded directly in Rust, JavaScript/TypeScript, Elixir, and Java/Kotlin (Maven). See Tools & SDKs for the full SDK documentation for each language. More languages are coming soon.

Editor support

Install the CLI, then use the VS Code/Cursor extension or point any LSP client at lemma lsp (stdio). The extension invokes lemma lsp automatically.

Docker

docker pull ghcr.io/lemma/lemma:latest

Supports linux/amd64 and linux/arm64.