What problem does it solve? Generated browser games often ship broken: inverted steering controls, sideways 3D models, frame-rate-dependent movement, silent audio on mobile, and blank canvases in production builds. This Skill provides the correctness rules and per-genre playbooks needed to produce a playable, performant game in a TanStack Start + React app. ## Core Features & Use Cases - Game loop and timing correctness: delta-time scaling, fixed-timestep physics with accumulators, and delta capping so gameplay is frame-rate independent. - 3D orientation and camera conventions: right-handed +Y-up rules, mesh-faces-+Z vs camera-looks-−Z guidance, and camera/movement agreement checks that prevent the classic backwards or sideways bugs. - Performance, assets, audio, and save: draw-call budgets, GPU resource disposal, object pooling, Web Audio unlock on first gesture, localStorage saves with migrations, and game-feel juice. - Per-genre playbooks and engine references: FPS, platformer, racing, match-3/tetris, voxel, tower defense, and more, plus deep references for three.js/R3F/rapier, Babylon.js, Phaser, ECS, AI pathfinding, and collision physics. - Use Case: Ask for a 3D racing game and get an R3F route with a Rapier character controller, correct A/D steering signs verified by a self-test, instanced track props, mobile touch controls, and a production build that renders. ## Quick Start Build a 2D platformer game with keyboard and touch controls using the building-games skill.