A public registry
for business rules
Search through business rules from organizations around the world.
LemmaBase
Open rules platform
LemmaBase is where teams publish Lemma specs, for the world to find and use. Each public repository gets a stable address, a published snapshot, and specs you can open in the browser without installing anything.
Discover
Search by rule name, repository, or publisher handle. Follow links to read the exact published text behind a decision.
Publish
Make a repository public when you are ready to share. Your specs stay versioned; the registry always points at the current publication.
Audit
Temporal versioning records what was live when. Compliance and operations teams can trace which rules applied on a given date.
More relevant than ever
Why we need business rules in the age of AI
Pull the logic out of the black box. Give your agents ground rules with Lemma and you got magic.
Agent guardrails
Define how AI makes business decisions, with strict, verifiable constraints.
Compliance built-in
Auditable, verifiable logic that ensures regulatory compliance.
Human readable
Stakeholders can read and validate rules without needing to code.
Open source
Your business logic is yours to own, control and run anywhere you want.
Designed for clarity, built for performance
A language that means business
Easy to understand
No PHD required. Lemma rules read like natural language. Business stakeholders can read and validate Lemma specs directly.
Run anywhere
Run Lemma anywhere: browser, server, or edge. The Rust-based engine compiles to WebAssembly for universal execution.
AI agent ready
Define ground rules that autonomous agents must follow. Verifiable constraints for non-human decision makers.
Version control
Treat business logic carefully. Seamless workflow for tracking changes, reviews, and rollbacks.
Unit-aware
Rules for kilograms handle pounds just fine. Conversions are automatic and many units are built-in.
Composing business logic
Modularize your rules. Import and reuse rules across different specs for better organization.
Inverse reasoning
Ask 'why' and get an answer. Explainability is built-in, allowing you to trace how decisions were made.
Safety constraints
Explicitly forbid certain outcomes. Define safety constraints that override all other rules.
Consult in the browser
Experience the power of Lemma directly in your browser. No installation required.
Try it outCommon questions
Answers about Lemma, the rules language, and LemmaBase, the public registry.
Lemma is a simple, declarative language designed for both humans and machines. Unlike traditional engines that are often opaque or tied to specific platforms, Lemma delivers an open standard and rules engine that you can run anywhere, without any dependencies.
AI agents are powerful but unpredictable. Business rules provide deterministic guardrails, ensuring that your agents operate within safe, compliant, and logical boundaries defined by your business.
Yes! Lemma's syntax is designed to be readable by anyone. We are developing a visual editor too, that allows non-technical stakeholders to create and validate rules without writing code.
Yes, the core Lemma engine is open source. We believe that the foundational logic layer of your business should be transparent, accessible, and portable.
Since Lemma compiles to WebAssembly, you can run it directly in any modern browser. Simply import the WASM module and execute your rules client-side with near-native performance.