---
agentTools:
  projectIndex: https://docs.orderful.com/llms.txt
---

# Rules: Test Expressions

<br />

We've updated our rules engine to make it safer to develop new rules without impacting your live transactions.

### What's New? ✨

Users can now define separate rule expressions for `live`and `test` transactions.

* **Synced** By default, rules will apply to both streams

* Users can **split** a rule and write different expressions for the different streams

* Bring them back in sync by duplicating one expression to the other stream

* Create **Test Only** rules to try out new rules without impacting `live` transactions

See more in [this guide](https://docs.orderful.com/update/docs/live-vs-test-rules)