@limitlayer/core

LimitLayer

A modern, framework-agnostic rate limiting library for Node.js and TypeScript.

LimitLayer is designed to be fast, extensible, and easy to integrate. It separates the core rate-limiting engine from framework adapters, allowing the same limiter to work across Express today and other frameworks in future releases.

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Architecture

flowchart TD

    App[Application]

    Express["@limitlayer/express"]

    Core["@limitlayer/core"]

    Engine[Decision Engine]

    Matcher[Rule Matcher]

    Registry[Algorithm Registry]

    Algorithm[Fixed Window Algorithm]

    Store[Memory Store]

    App --> Express
    Express --> Core

    Core --> Engine
    Engine --> Matcher
    Engine --> Registry
    Registry --> Algorithm
    Engine --> Store

Features

• High-performance TypeScript implementation
• Framework-agnostic core
• Official Express adapter
• ESM + CommonJS support
• Built-in Fixed Window algorithm
• Extensible algorithm registry
• Pluggable storage architecture
• Type-safe public API
• Simple configuration

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Packages

Package	Description
@limitlayer/core	Core rate limiting engine
@limitlayer/express	Express middleware

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Installation

Core

npm install @limitlayer/core

Express

npm install @limitlayer/core @limitlayer/express express

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Quick Start

import {
  MemoryStore,
  createLimitLayer,
} from "@limitlayer/core";

const limiter = createLimitLayer({
  storage: new MemoryStore(),
  rules: [
    {
      path: "/login",
      algorithm: "fixed-window",
      limit: 5,
      window: "1m",
    },
  ],
});

const result = await limiter.consume({
  method: "POST",
  path: "/login",
  ip: "127.0.0.1",
  headers: {},
  query: {},
});

console.log(result);

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Express Example

import express from "express";

import { MemoryStore } from "@limitlayer/core";
import { limitLayer } from "@limitlayer/express";

const app = express();

app.use(
  limitLayer({
    storage: new MemoryStore(),
    rules: [
      {
        path: "/login",
        algorithm: "fixed-window",
        limit: 5,
        window: "1m",
      },
    ],
  })
);

app.post("/login", (_, res) => {
  res.json({
    success: true,
  });
});

app.listen(3000);

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Built-in Algorithms

Algorithm	Status
Fixed Window	Available
Sliding Window	Planned
Sliding Log	Planned
Token Bucket	Planned
Leaky Bucket	Planned

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Storage

Storage	Status
MemoryStore	Available
RedisStore	Planned

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Roadmap

v0.1

• Core engine
• Memory storage
• Fixed Window algorithm
• Express adapter

v0.2

• Redis storage
• Sliding Window
• Token Bucket
• Leaky Bucket
• Sliding Log

Future

• Fastify adapter
• Hono adapter
• Next.js adapter
• Analytics dashboard
• Hosted SaaS

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Development

Clone the repository:

git clone https://github.com/gargavi-oss/limitlayer.git
cd limitlayer
pnpm install

Build all packages:

pnpm build

Run tests:

pnpm test

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Contributing

Contributions, bug reports, feature requests, and discussions are welcome.

1. Fork the repository
2. Create a feature branch
3. Commit your changes
4. Open a Pull Request

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License

MIT License.

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Built with using TypeScript.