GoRules ZEN Engine

ZEN Engine, whose core is written in Rust, keeps decisions as portable JSON, and loading that JSON stays your choice: file system, database or a service call. The aim is business logic that a rule owner can read and a machine can run.

Conditions are written in the ZEN Expression Language, phrased the way the business states them, with the developer view one toggle away and only one source of truth behind both. A decision can be modeled as a graph on a visual canvas of decision tables, switches, expressions, functions and reusable sub-decisions, or as a policy document with prose, typed data models and tables. Both compile to the same engine and return the same answers.

• Workspace analysis: static type checking across policies and graphs, with type flow, exhaustiveness checking and write-conflict detection before anything runs.
• Per-column collect: an output column can collect values across every matching row while the rest of the table stays first-match.
• Pre-compiled engine: decisions are parsed and compiled once at load, so evaluation is allocation-light and repeat-safe.
• Hardened runtime: out-of-range numbers, arithmetic overflow and malformed input return errors or nulls instead of crashing the process.

Native bindings reach Node.js, Python, Go, Java, Kotlin and .NET, plus iOS and Android packages, and the same decision evaluates identically on each. GoRules is the commercial platform around this MIT licensed engine. A free online editor with a simulator is available, and the React JDM Editor can be embedded in a product of your own.