ARE — Action Rule Event Engine

Zero dependency, cross-platform, lightweight event-rule-action engine.

Game, web, mobile, desktop — one engine, same logic everywhere.

Event ───→ Middleware ───→ Rule Matching ───→ Action Execution
              │               │                    │
           before/after    conditions + matchMode  settings + context
                           priority + groups

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What Does It Do?

There is a recurring pattern in every project: "When something happens, if certain conditions are met, do these things."

ARE solves this pattern with a single engine:

Concept	Description	Example
Event	Something that happened	order.created, player.died, user.login_failed
Rule	Which event, which conditions, what to do	"If order exceeds $5000, send VIP email"
Condition	Determines whether a rule should execute	total > 5000, zone == "boss", attempts >= 3
Action	The work to be performed	Send email, deal damage, update stock, show UI
Middleware	Intercepts the pipeline	Logging, auth checks, audit trails
Context	Shared data throughout the flow	Passing data between actions

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Quick Start

C# (.NET)

var engine = new AreEngine();

engine.RegisterAction("send_email", async (ctx, s) =>
{
    Console.WriteLine($"Email: {s.Get("template")}");
});

engine.AddRule(
    Rule.Create("vip_order")
        .On("order.created")
        .WhenGreaterThan("total", 5000.0)
        .Then("send_email", s => s.Set("template", "vip_welcome"))
);

await engine.FireAsync("order.created", e => e.Set("total", 7500.0));
// → Email: vip_welcome

JavaScript / TypeScript

const { AreEngine, Rule } = require('are-engine-core');

const engine = new AreEngine();

engine.registerAction('send_email', async (ctx, s) => {
  console.log('Email:', s.get('template'));
});

engine.addRule(
  Rule.create('vip_order')
    .on('order.created')
    .whenGreaterThan('total', 5000)
    .then('send_email', s => s.set('template', 'vip_welcome'))
);

await engine.fire('order.created', e => e.set('total', 7500));
// → Email: vip_welcome

Dart / Flutter

import 'package:are_engine_core/are_engine_core.dart';

final engine = AreEngine();

engine.registerInlineAction('send_email', (ctx, s) async {
  print('Email: ${s.get<String>('template')}');
});

engine.addRule(
  Rule.create('vip_order')
      .on('order.created')
      .whenGreaterThan('total', 5000.0)
      .then('send_email', (s) => s.set('template', 'vip_welcome')),
);

await engine.fire('order.created', (e) => e.set('total', 7500.0));
// → Email: vip_welcome

---

Features

• Zero dependency — No external packages required
• Fluent Builder — Rule.Create().On().When().Then() chaining
• MatchMode — All (AND), Any (OR), None (NOT), ExactlyOne (XOR)
• 9 comparison operators — Equal, GreaterThan, Contains, In, and more
• Middleware — Before/after pipeline interception
• Rule groups — Bulk enable/disable
• Priority ordering — Higher priority rules execute first
• Pipeline control — StopPipeline, SkipRemainingActions
• Dynamic management — Add/remove/enable/disable rules at runtime
• Result reporting — Which rules fired, which were skipped and why
• Async — Fully asynchronous pipeline

---

Repository Structure

Folder	Description
ARE.Core	Core engine — NuGet package (C#)
are-core	JavaScript/TypeScript port — npm package
ARE.Core.Tests	xUnit tests
ARE.Examples.Game	Game scenario example (C#)
ARE.Examples.WebApi	E-commerce scenario example (C#)
ARE.Examples.Desktop	POS / desktop scenario example (C#)
are_engine_core	Dart/Flutter port — pub.dev package
are-core/examples	JavaScript examples (Game, E-commerce, Desktop)

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Platform Support

Platform	Package
WinForms / WPF / MAUI	NuGet: ARE.Core
ASP.NET Core / Blazor	NuGet: ARE.Core
Unity / Godot	NuGet or .dll (netstandard2.1)
Node.js / Express	npm: are-engine-core
React / Vue / Angular	npm: are-engine-core
React Native / Electron	npm: are-engine-core
Flutter (iOS / Android / Web)	pub: are_engine_core
Dart CLI / Server	pub: are_engine_core

---

Installation

C#:

dotnet add package ARE.Core

JavaScript:

npm install are-engine-core

Dart / Flutter:

dependencies:
  are_engine_core: ^1.0.0

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Documentation

• ARE.Core (C#) — Detailed API & Usage
• are-engine-core (JS/TS) — Detailed API & Usage
• are_engine_core (Dart/Flutter) — Detailed API & Usage

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License

MIT