Model Trainz

A cozy 3D incremental game about building a railway, one piece of track at a time. It runs in the browser and as an iOS and Android app, in English, Spanish or Italian, and your Game ID lets you carry on from any device.

Gameplay

Your little steam train waits at a station. Between it and the next station there's nothing but countryside, so it's up to you to build the line.

• Start playing. Enter your name on the start screen and press Play. Have the Game ID of an earlier game? Enter it too and you'll continue that game.

• Lay track. Click or tap anywhere on the scene, press or hold Space, or use the Lay track button. Each click lays track in front of the train; hold to keep going.

• Run the line. When the track reaches the next station the train departs, chuffs along the new stretch and collects fares when it pulls in. Then the next leg begins.

• Upgrade. Spend coins in the Upgrades panel on the right (collapse it with Hide/Show; on phones it's a drawer you pull out from the right edge):

  Upgrade	Effect
  Bigger Shovels	+1 track piece per click
  Steel Rails	+$1 for every track piece laid
  Track Gang	+0.5 pieces/sec, laid automatically
  Hotter Boiler	+20% train speed
  Fare Hike	+25% station fares
  Extra Carriage	+1 carriage on the train, +50% fares
  Golden Spikes	+2% chance that a click pays out 20×

• Visit the Depot. The Depot tab next to Upgrades sells new train sets. The one in service sets the train's top speed and fares; once bought you can switch between them for free.

  Train set	Price	Locomotive + coaches	Bonus
  Heritage Steam	Free	Steam tank engine + teak coaches	—
  Evergreen Express	$50K	Mainline diesel + modern coaches	+50% speed, +50% fares

• Pick up where you left off. Your game pauses when you close the tab. Next time, the start screen welcomes you back with a Continue button. To carry on from another device, copy your Game ID from the Game panel and enter it on the start screen there, or open the same page address there (it includes the ID). Anyone with the ID can play that game, so keep it to yourself.

• Pick a view. Press V (or use the toggle bottom left) to switch between the overhead Diorama and the first-person Cab. Scroll to zoom the diorama; in the cab, drag or use the arrow keys to look around and C to re-centre. The Evergreen Express cab has a full driver's desk, with power and brake handles that move and live speed and power gauges.

• Choose a language. The game follows your browser's language (English, Spanish or Italian, falling back to English). Change it from the start screen or in Settings.

• Settings (top right) cover language, sound, volume, graphics quality (Auto, Low, Medium, High, Ultra) and the full list of controls.

Progress is saved automatically on your device and online: every minute, a few seconds after you buy something or reach a station, and when you leave the page. If the server can't be reached, progress is kept on your device until it can.

Toolstack

Area	Tools
Framework	Next.js 16 (App Router), React 19, TypeScript (strict)
3D rendering	three.js via React Three Fiber and drei
Post-processing	postprocessing + @react-three/postprocessing (bloom, SSAO, tone mapping, SMAA, vignette)
World generation	simplex-noise terrain, meshed in Web Workers
State	Zustand
Online saves	/api/games/[id] route handler + Supabase table
UI	Tailwind CSS 4
Languages	Typed message dictionaries in src/i18n (English, Spanish, Italian), no i18n library
Mobile apps	Capacitor 8 (iOS and Android) around a static export of the game
Audio	Web Audio API (all sound effects synthesised at runtime)
Testing and quality	Vitest, Playwright, ESLint, Prettier
Package manager	pnpm

All models, textures and sounds are generated procedurally; there are no external art assets.

Getting started

Run locally

You need Node.js 20 or newer and pnpm. The pnpm version is pinned in package.json; run corepack enable once to use it automatically.

pnpm install
pnpm dev

Open http://localhost:3000.

Online saves work locally without any setup: each game is stored as a JSON file in .data/games/. To use Supabase instead, put SUPABASE_URL and SUPABASE_SECRET_KEY in .env.local (set GAME_STORE=local to force the local files even then).

This is the beginning of the README. Read the rest at the original. Read the full README ↗