lemma

A pure, declarative language for business rules. Command-line interface for Lemma.

Run Lemma without installing anything globally:

npx lemma help

Or install globally:

npm install -g lemma
lemma --help

How it works

This package is a thin Node.js launcher. The actual lemma binary is shipped as a platform-specific optional dependency (one of @lemmabase/cli-linux-x64, @lemmabase/cli-linux-arm64, @lemmabase/cli-darwin-x64, @lemmabase/cli-darwin-arm64, @lemmabase/cli-win32-x64, @lemmabase/cli-win32-arm64). npm installs only the package matching your OS and CPU; the launcher then execs the native binary directly. No download steps, no postinstall scripts, works offline.

Supported platforms

• Linux x86_64 (musl, statically linked)
• Linux aarch64 (musl, statically linked)
• macOS x86_64
• macOS aarch64 (Apple Silicon)
• Windows x86_64
• Windows aarch64 (ARM64)

If your platform is not supported, install via Cargo instead:

cargo install lemma

Common commands

npx lemma run shipping
npx lemma run tax_calculation --rules=tax_owed
npx lemma run tax_calculation income=75000 filing_status="married"
npx lemma list
npx lemma schema pricing
npx lemma server --prefix ./examples --port 8012

Each command supports --help.

Documentation

• CLI reference: https://github.com/lemma/lemma/blob/main/documentation/reference/cli.md
• Learn guide: https://github.com/lemma/lemma/blob/main/documentation/learn/readme.md
• Examples: https://github.com/lemma/lemma/tree/main/documentation/examples

Local development

To rebuild and test this package locally:

cargo build --release -p lemma
mkdir -p /tmp/lemma-bins/linux-x64
cp target/release/lemma /tmp/lemma-bins/linux-x64/lemma
node cli/packages/npm/build.js --binaries /tmp/lemma-bins
cd cli/packages/npm/dist/lemma && npm pack --dry-run

End-to-end smoke test:

cd cli/packages/npm/dist
npm pack ./lemma ./platforms/linux-x64
mkdir -p /tmp/lemma-smoke && cd /tmp/lemma-smoke
npm init -y >/dev/null
npm install /path/to/cli/packages/npm/dist/lemma-*.tgz \
            /path/to/cli/packages/npm/dist/lemmabase-cli-linux-x64-*.tgz
npx lemma --help

License

Apache-2.0