Frontline Command, a browser RTS in one HTML file

The full story

Frontline Command is a real-time strategy game in a single HTML file under 500 KB: build a base, mine ore, raise an army and destroy every enemy building. It has four factions with their own units and towers, power management, missiles and a superweapon, aircraft, engineers that capture buildings, fog of war and five map styles, and every unit is drawn in code on a canvas.

The maker spent about an hour on it in the gaps while Claude Code worked on another project. Claude Code wrote nearly all of it in TypeScript with Vite and Vitest. The simulation is deterministic, with no DOM and no random calls, and all content lives in one definitions file. Balance was set by simulation: Claude built a computer-versus-computer harness and ran 72 games, narrowing the factions' win rates from 44 to 54% down to 46 to 53%.

It is version 0.0.1 and the maker openly calls it close to Command & Conquer. It is playable as a Claude artifact and saves itself between visits.