Holster is a real-time data synchronisation service that seamlessly connects devices using Node.js, Deno, Bun or the browser. Built with modern ES modules, it features end-to-end encryption, intelligent conflict resolution, and cross-platform compatibility.

✨ Real-time sync across all connected devices
🔐 Built-in encryption with user authentication
⚡ Zero configuration with smart performance optimisation
🌐 Universal compatibility - works everywhere JavaScript runs

Try it out at holster.haza.website!

A build version of Holster is also provided using esbuild, to run in production.

Check out the Github Wiki for how to get started using the API, and for more information.

Quick Start

• Clone this repo

Then using Docker

• Run docker build -t holster . to build the image
• Run docker run -p 3000:3000 -p 8765:8765 holster to start the server

Or run locally

• Run npm install
• Run the server with node src/index.js

Once the server is running

• Open http://localhost:3000/examples/index.html in the browser.
• You will then also have access to the Holster API via the holster object in the console

Development

• When modifying src files run: npx prettier src --write && npm run build
• When modifying tests run: npx prettier test --write
• To run the tests use: npm run test