Package Exports

simkit-core
simkit-core/dist/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (simkit-core) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

simkit-core

A lightweight, type-safe Entity-Component-System (ECS) library for TypeScript

Performance

Latest benchmark results for version 0.8.1 (11/4/2025):

Benchmark	Operations/sec
Packed Iteration (5 queries)	13,757
Simple Iteration	11,544
Fragmented Iteration	28,109
Entity Cycle	3,359
Add/Remove Component	6,948

Benchmark Descriptions

Packed Iteration (5 queries): Tests core iteration overhead with multiple queries on 1,000 entities
Simple Iteration: Tests independent systems on entities with different component combinations
Fragmented Iteration: Tests iteration through fragmented dataset (26 component types)
Entity Cycle: Tests entity creation and destruction performance
Add/Remove Component: Tests component addition and removal on existing entities

Benchmarks run on Node.js v22.16.0 on linux

Installation

Using npm

npm install simkit-core

Using yarn

yarn add simkit-core

Using pnpm

pnpm add simkit-core

From GitHub

npm install github:Pekmen/simkit-core

Development

# Clone the repository
git clone https://github.com/Pekmen/simkit-core.git
cd simkit-core

# Install dependencies
npm install

# Build and test
npm run build
npm test

# Run examples
npx tsx examples/basic.ts

Features

🚀 High Performance: Optimized for game development and simulations
🔒 Type Safe: Full TypeScript support with type inference
🧩 Simple API: Easy to learn and use
🔧 Flexible: Supports complex component relationships
📦 Lightweight: Minimal dependencies and small bundle size

Quick Start

import { World, System, defineComponent } from "simkit-core";

// Define components
interface Position {
  x: number;
  y: number;
}
interface Velocity {
  dx: number;
  dy: number;
}

const Position = defineComponent<Position>("Position", { x: 0, y: 0 });
const Velocity = defineComponent<Velocity>("Velocity", { dx: 0, dy: 0 });

// Create a system
class MovementSystem extends System {
  private query = this.world.createQuery({ with: [Position, Velocity] });

  update(deltaTime: number): void {
    for (const entity of this.query.execute()) {
      const pos = this.world.getComponent(entity, Position);
      const vel = this.world.getComponent(entity, Velocity);
      if (pos && vel) {
        pos.x += vel.dx * deltaTime;
        pos.y += vel.dy * deltaTime;
      }
    }
  }
}

// Create world and add system
const world = new World();
world.addSystem(new MovementSystem(world));

// Create entity
const player = world.createEntity();
world.addComponent(player, Position, { x: 0, y: 0 });
world.addComponent(player, Velocity, { dx: 1, dy: 1 });

// Run simulation
world.update(0.016); // 16ms delta time

API Reference

World

const world = new World();

// Entities
const entity = world.createEntity();
world.destroyEntity(entity);

// Components
world.addComponent(entity, ComponentType, data);
world.removeComponent(entity, ComponentType);
world.getComponent(entity, ComponentType);
world.hasComponent(entity, ComponentType);

// Systems & Updates
world.addSystem(system);
world.update(deltaTime);

// Queries
const query = world.createQuery({ with: [Position, Velocity] });
for (const entity of query.execute()) {
  /* ... */
}

// Serialization
const snapshot = world.save();
world.load(snapshot, [Position, Velocity]);

defineComponent

interface Health {
  current: number;
  max: number;
}
const Health = defineComponent<Health>("Health", { current: 100, max: 100 });

// Partial data uses defaults
world.addComponent(entity, Health, { current: 80 }); // max = 100

System

class HealthSystem extends System {
  private query = this.world.createQuery({ with: [Health] });

  update(deltaTime: number): void {
    for (const entity of this.query.execute()) {
      const health = this.world.getComponent(entity, Health);
      if (health && health.current <= 0) {
        this.world.destroyEntity(entity);
      }
    }
  }
}

License

MIT