> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gorules.io/llms.txt
> Use this file to discover all available pages before exploring further.
# BRE and BRMS
> Understand how the ZEN Engine (BRE) and GoRules BRMS work together.
export const BREBRMSDiagram = () => {
return
{}
{}
Business Rules Management System
(BRMS)
{}
Business Rules Engine
(BRE)
{}
{}
GoRules BRMS
Enhanced Authoring Capabilities
Rule Repository with Version Control
Debugging and Simulation
Audit Logs
{}
ZEN Engine (Open Source)
Rule Execution
Deterministic If-then Logic
Library - Foundational Element
;
};
GoRules consists of two main parts: the **BRMS** (Business Rules Management System) for managing rules, and the **ZEN Engine** (BRE) for executing them.
The **BRMS** is the management platform where you author, test, version, and publish rules. It includes the ZEN Engine internally for testing and direct API evaluation.
The **ZEN Engine** is the high-performance execution engine. It runs inside the BRMS, and also powers the Agent and SDKs that execute rules in your environments.
## GoRules BRMS
The BRMS is the recommended starting point for most organizations. It provides everything you need to manage business rules at scale.
| Capability | Description |
| ------------------- | ------------------------------------------------------ |
| **Visual editor** | Drag-and-drop interface for building decision graphs |
| **Collaboration** | Multiple users, projects, and access controls |
| **Version control** | Track changes, compare versions, roll back |
| **Testing** | Built-in simulator to validate rules before publishing |
| **Releases** | Publish rules to different environments |
| **Audit logs** | Track who changed what and when |
| **API access** | Evaluate rules directly or publish to Agents/SDKs |
### When to use BRMS
* Business users need to create or modify rules
* You need version control and audit trails
* Multiple teams collaborate on rules
* You want a managed workflow for publishing rules
## ZEN Engine
The ZEN Engine is the open-source rules execution engine that powers all of GoRules. It's written in Rust for maximum performance.
| Capability | Description |
| ------------------- | -------------------------------------------------------------- |
| **Sub-millisecond** | Evaluates most decisions in under 1ms |
| **Cross-platform** | Native SDKs for Node.js, Python, Go, Rust, Java, Kotlin, Swift |
| **Embeddable** | Runs in-process with your application |
| **Open-source** | Available on [GitHub](https://github.com/gorules/zen) |
### Standalone usage
You can use the ZEN Engine without the BRMS if you only need rule execution and will manage rule files yourself.
| Component | Purpose |
| ------------------------------------------------------ | ---------------------------------- |
| [ZEN Engine](https://github.com/gorules/zen) | Core execution library |
| [JDM Editor](https://github.com/gorules/jdm-editor) | React component for building rules |
| [Standalone Editor](https://github.com/gorules/editor) | Desktop app for editing JDM files |
**When to use standalone:**
* Building a product with embedded rules
* You have your own storage and versioning
* Developers manage all rules (no business user access needed)
* Maximum control over the rules lifecycle
When using the ZEN Engine standalone, you're responsible for storing, versioning, and distributing JDM files to your applications.
## Using them together
Organizations often use both BRMS and ZEN Engine together when they need maximum performance:
1. **Author in BRMS** — Business users create and test rules in the visual editor
2. **Publish releases** — Rules are published to object storage (S3, Azure, GCS)
3. **Execute via SDK** — ZEN Engine runs embedded in your application
With the embedded SDK, rule evaluation is sub-millisecond because there's no network overhead — no REST API calls, no serialization. The engine runs in-process with your application.
```mermaid theme={null}
flowchart LR
brms["BRMS (author & publish)"] --> storage["Object Storage"]
storage --> app
subgraph app["Your Application"]
sdk["ZEN Engine SDK"]
end
```
## Choosing your approach
| Scenario | Recommendation |
| ----------------------------------------- | ------------------------------ |
| Business users edit rules | BRMS |
| Need audit trails and version control | BRMS |
| Team collaboration | BRMS |
| Building a product with embedded rules | ZEN Engine standalone |
| Developers manage all rules | Either (BRMS adds convenience) |
| Maximum performance, minimal dependencies | ZEN Engine standalone |
Most organizations start with the BRMS and use Agents or SDKs for production execution. The standalone ZEN Engine is best suited for product teams embedding rules into their own software.