TAIL GOAL

Score in their goal. Yours follows you.

2–4 tiny cars each tow their own goal on a rope, and there's one ball. Bump, boost, bend shots and ram rivals to swing their goal open, all in a floodlit pixel-crowd stadium.

Play: https://tail-goal.bc-server.workers.dev (keyboard: WASD/arrows to drive, Space to boost, Esc for the menu)

Built with OpenAI Codex and Anthropic Claude working together. The two agents split the work: rules/simulation/server and the stadium visual pass on one side, client flow/online/leaderboard/tournaments on the other, and they reviewed each other's work.

Features

• Online multiplayer: quick match, private rooms with an invite link (or join by code), drop-in for late friends, and bots in empty seats. The server is authoritative (Cloudflare Workers + Durable Objects, 60 Hz).
• Global XP leaderboard: guest profiles with no login. All XP is awarded by the server.
• Tournaments: 8-player single-elimination 1v1 brackets, with bots filling empty slots and the biggest XP in the game.
• Rules:
  • The goal mouth faces your car, so only front-entry shots count.
  • Conceding costs you a point (never below 0).
  • 2-minute clock, and reaching 5 wins early.
  • Overtime is for tied leaders only, capped at 60s (knockouts can't draw).
  • The conceder kicks off.
• Feel:
  • momentum bumps (you keep your speed; they get shoved),
  • boosted rams swing the victim's goal open,
  • curved "finesse" shots,
  • the ball pops up out of rattling scrums,
  • a perfect-game bonus for winning 5-0.
• Onboarding: a 45-second playable tutorial on first visit (replay with H).
• Presentation: three.js stadium, 4,500 instanced pixel-art fans, broadcast-style UI, procedural music and sound, and adaptive quality for low-power laptops.

Run locally

npm install
npx playwright install chromium   # only for the browser tests
npm run server                    # game server on :8790 (wrangler dev)
npm run dev                       # client on :5182

Tests

npm test               # simulation regressions: physics, nets, kickoff, clock/overtime, teleport, bumps
npm run test:online    # two real browsers: friends room, join by link, match, rematch, quick match
npm run test:ladder    # profiles, server-awarded XP, leaderboard, abuse cases
npm run test:tutorial  # first-visit tutorial: drive, a real keyboard goal, replay and skip
npm run test:tourney   # a full bracket with 2 humans + 6 bots (start the client with ?short=1 support on localhost)

Layout

• protos/tail-goal/: the game. sim.ts is the deterministic 60 Hz simulation shared by client and server; main.ts handles flow, menus and HUD; render3d.ts, stadium.ts, crowd.ts and juice.ts are the presentation.
• tailgoal-server/: the Cloudflare Worker: rooms, lobby, ladder (ladder.ts) and tournaments (tourney.ts).
• tools/: end-to-end and balance probes.
• docs/: design briefs and results from each pass.

Deploy

npm run deploy builds the client into the Worker's assets and deploys to Cloudflare (wrangler login required).