The app is based on the ReactJS JavaScript framework and TDLib (Telegram Database library) compiled to WebAssembly. Try it here.
Install node.js.
Install dependencies with:
npm install
This will install all the needed dependencies.
All TDLib files will be installed into node_modules/tdweb/dist/ folder. Manually copy them into the public folder with:
cp node_modules/tdweb/dist/* public/
Run the app in development mode with:
npm run start
Open http://localhost:3000 to view it in the browser.