diff-invaders

Space Invaders above the Claude Code prompt where every wave is the code Claude just wrote: each line an Edit or Write added becomes a row of the formation and every two characters one alien, so you shoot your own diff. Ship, one shot at a time, bombs, three lives, best score. Zero tokens: the mod answers every key and click itself and never asks the model anything.

Play

1. /diff-invaders opens the board above the prompt (/diff-invaders stop or the close button closes it).
2. Click the board to give it the keyboard; Esc gives the keyboard back to the prompt.
3. ← → or a d move the ship, Space, ↑ or a click fires (one shot in the air at a time), p pauses, r shoots a demo wave.
4. An alien is 10 points, a cleared wave 50. A bomb on the ship costs a life; a formation that lands ends the game.

The waves come from Claude: every Edit or Write that goes through is read after it runs, its added lines (up to six) become the rows of the next formation, and every two characters of a line become one alien, spelled with those characters. Waves queue up while you clear the current one, so a long refactor is a long fight. r plays a built-in wave while Claude has not written anything yet.

Your best score is kept in the plugin's store across sessions.

Install

npx claude-code-templates@latest --mod games/diff-invaders
CLAUDE_CODE_ENABLE_FUNCTION_HOOKS=1 claude

It is written to .claude/skills/diff-invaders/, which Claude Code auto-loads as diff-invaders@skills-dir. For one session with hot reload: CLAUDE_CODE_ENABLE_FUNCTION_HOOKS=1 claude --plugin-dir .claude/skills/diff-invaders. claude plugin validate .claude/skills/diff-invaders prints every event it hooks and every $ call it makes.

How it is built

hooks/register.tsx is the hooks module: it registers /diff-invaders, mounts the board on the AbovePrompt band and keeps the score in $.store. hooks/games/*.ts is the game's logic, pure functions with no drawing, and hooks/boards/*.tsx is the surface module that draws it in two-character cells on the drawing thread and takes the keys and the mouse. Written for aitmpl.com against Anthropic's published function-hooks declarations.

Requirements

• Claude Code 2.1.269 or later (the first build whose function hooks draw above the prompt) with CLAUDE_CODE_ENABLE_FUNCTION_HOOKS=1. The $ API is early access and may change between releases.
• An interactive terminal that reports the mouse. Nothing draws in claude -p, the desktop app or mobile.
• A terminal font with box-drawing and block characters.

A clone of the genre, not affiliated with or endorsed by the original publisher.