Flappycar
A one-button browser game: a sports car on cold-gas thrusters, a daily course everyone shares, and ghost races sent to friends as a URL with no backend at all.
Problem
I wanted a small game that was fun to share: you beat a score, you send a link, and your friend races you. The usual way to do that is accounts, a database of runs and an API, and I did not want to operate any of that for a toy.
Approach
Flappycar is about 4,900 lines of plain JavaScript with no framework and no build step beyond a single bundling script. The physics runs at a fixed step, the course is a pure function of a seed, and a run is just the list of step numbers on which the player tapped. That makes a whole replay small enough to pack into a couple of hundred bytes of URL, so a challenge link carries the entire run and the recipient’s browser replays it as a translucent ghost beside them. The leaderboard rides along in the same link.
The site is static on Cloudflare Pages with one tiny Pages Function for an anonymous play counter. Share cards are rendered at build time so social previews are stable.
Outcome
- Ships as a single page that works from
file://as well as the web, and loads in well under a second on a phone. - Daily courses, medals, liveries, set pieces and ghost races, all without a server to run or a database to back up.
- The design of the ghost links is written up in A whole replay in a URL.