v2.0

GoRules Version 2 is here - redesigned, now with managed cloud.GoRules Version 2 is here!

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Kotlin SDK

Kotlin
rules engine.

Open source Kotlin rules engine with coroutine support. Idiomatic API for business rule evaluation on JVM and Android.

Documentation GitHub

Up and running
in three steps.

Install the SDK, load a decision graph, evaluate - the same JSON your team edits in the visual editor runs in your process.

Step 1

Add the Dependency

Add the GoRules engine to your Gradle project.

// build.gradle.kts
dependencies {
    implementation("io.gorules:zen-engine-kotlin:2.0.0")
}

Step 2

Load a Decision

Create an engine and load your decision graph.

import io.gorules.zen_engine.kotlin.JsonBuffer
import io.gorules.zen_engine.kotlin.ZenEngine
import java.io.File

val engine = ZenEngine()
val content = File("./decision.json").readText()
val decision = engine.createDecision(JsonBuffer(content))

Step 3

Evaluate Rules

Pass your input data and receive the decision result.

val context = JsonBuffer("""
    {
      "customer": { "tier": "premium", "country": "US" },
      "cart": { "total": 150, "items": 3 }
    }
""")

val result = decision.evaluate(context, null)
println(result.result)
// {"discount":15,"freeShipping":true}

Why
Kotlin?

Built for performance and developer experience - native speed with an API that feels at home in your codebase.

Kotlin-Native API

Idiomatic Kotlin with extension functions, null-safety, and type inference throughout.

Coroutine Support

Suspend functions for non-blocking rule evaluation. Perfect for Ktor and other async frameworks.

Android Compatible

Full Android support for embedding business rules directly in mobile applications.

About the Kotlin SDK

GoRules provides first-class Kotlin support for business rules management. Shipped as a dedicated Kotlin artifact with suspend functions throughout, it delivers an idiomatic development experience with coroutine support out of the box.

The Kotlin SDK embraces modern JVM development practices with suspend functions, extension methods, and null-safety throughout. Whether you're building with Ktor, Spring Boot, or Android applications, GoRules integrates naturally with your Kotlin codebase.

Leverage Kotlin's expressive syntax alongside GoRules' powerful rule engine. The SDK supports all GoRules features including decision tables, expressions, and complex rule graphs, all accessible through a clean, Kotlin-native API.

See the public Zen Engine benchmarks

Build with Kotlin.
Govern with GoRules.

The engine is open source and free forever - add the GoRules BRMS when your team needs versioning, approvals, and an audit trail.

Get started Book a demo

Kotlin rules engine.

Up and running in three steps.