Roofrail Endless Runner Game App

Overview

Roofrail is an endless runner built on Expo SDK 57 and React Native with the FluxNative kernel. The first screen is the game: a rail yard at dusk seen from behind the runner, three tracks running to the horizon, and the first swipe starts the run. Swipe left or right to change lane, up to jump a barrier, down to slide under a signal gantry; freight cars take a lane change. The yard speeds up from 9 to 18 m/s over three minutes.

With .env blank the game runs in sample mode: a sample player with a best of 1,842 m, 3,120 coins, two outfits, ten recent runs, missions half done and day 3 of the daily reward waiting. Everything the player does is kept on the device. Setting the Supabase values turns on the weekly board; setting the RevenueCat keys sells Plus.

Key features

• The game: ready, running, paused and over on one full-bleed screen, with the distance, coins and best in the HUD and a medal for each distance band at the end

• Rules in a pure engine (engine.ts), unit-tested: every row of obstacles leaves a passable lane, the first hazard is more than 1.5 s away, walls of three only after 400 m

• Shop: eight outfits, each with its own headwear (a cap, a beanie, headphones, the hood up, a bucket hat, a headlamp, a visor, goggles), some with a backpack, a scarf or a light trail, bought with coins; the runner shown big on the yard

• Missions: three at a time from real runs (jump 12 barriers in one run, collect 300 coins, run 500 m without jumping…), each a step harder the next time

• Daily reward: a 7-day ladder claimed once per device date; a skipped day waits instead of starting over

• Leaderboard: this week's board, rivals drawn as runners in their outfits and your place among them (a sample crew until Supabase is connected), and the phone's ten longest runs

• How to play: the three swipes drawn with the game's own sprites

• Settings: sound effects, vibration, reduce motion, Plus, How to play, About, Terms, Privacy and Delete my data

Screens

10 screens: the game (ready, running, paused, over), Shop, Missions, Leaderboard, How to play, Roofrail Plus, Settings, About, Terms of Use and Privacy Policy. One stack with no tab bar; the pushed screens follow the iOS 26 look in light and dark, the game keeps its dusk palette in both.

Game and backend

• One requestAnimationFrame loop while running, a pure step(run, dt) with dt clamped to 0.05 s, seeded randomness, swipes through PanResponder (touch, mouse and the preview's taps)

• The game folder reads app data through one hook (useGameProgress), so it lifts into another app

• Weekly board on Supabase: each player reads only their own rows, one anonymous sign-in per device, names made of the game's words (no free text to moderate)

• The server times every run: start_run records the start, and submit_score takes each run once and refuses a distance its time cannot reach

• The board's distance rule is the game's own speed curve, held to the engine by tests; nine sample runners fill the first week

• Delete my data clears the device and removes the player's anonymous sign-in, name and runs from the board

Monetisation

Roofrail Plus is one non-consumable in-app purchase sold through the App Store and Google Play with RevenueCat (react-native-purchases): every outfit, including one only Plus has, and double coins on every run. Access comes from the plus entitlement only, with Restore purchase on the Plus screen. Without RevenueCat keys the Plus screen shows the intended price marked as a sample, says purchases open in the App Store version, and never grants access. No ads, no loot boxes, nothing that pays out.

Setup

• Connect Supabase, apply the three migrations and allow anonymous sign-ins for the weekly board

• Connect RevenueCat with a roofrail_plus product and a plus entitlement to sell Plus

• Reskin the yard, the runner and the outfits in palette.ts, outfits.ts and art.tsx

• Replace the sample Terms of Use and Privacy Policy with your own