Caffeinatrix

The screen stays awake. Your jobs keep running. The rain keeps falling.

A fullscreen Matrix rain that keeps your Mac or PC from sleeping while long builds, training runs, or overnight prompts grind away. Named for the macOS caffeinate command it replaces, dressed up in green.

ﾊ 7 ｱ │ wake state: ON   │ display sleep: BLOCKED   │ vibe: immaculate

What it does

Launch it, and your machine renders an endless cascade of green code at fullscreen while holding the display awake. Close it, and your power settings go right back to normal. Nothing to remember to turn off, no terminal window to babysit.

Under the hood it asks the OS to block display sleep (Electron's powerSaveBlocker in prevent-display-sleep mode), so the screen stays lit and your background work never gets paused.

Easy on the panel. Every pixel is in constant motion, so there is nothing static to burn into an OLED or mini-LED display over a long overnight session. The rain is the screen saver and the keep-awake at the same time.

Install globally (npm)

Requires Node.js 18 or newer.

npm install -g @jameymcelveen/cafx
cafx

That installs the cafx command on your PATH and launches Caffeinatrix (fullscreen Matrix rain, display sleep blocked). The npm package name is scoped (@jameymcelveen/cafx); you still run cafx. npm also pulls in Electron as a dependency during install (a few hundred MB). After that, it is just cafx whenever you need the rain.

Upgrade later with:

npm update -g @jameymcelveen/cafx

Uninstall:

npm uninstall -g @jameymcelveen/cafx

Controls

| Key | Action | | -------------- | ----------------- | | Esc | quit | | Cmd/Ctrl + Q | quit | | F | toggle fullscreen |

Run from source (development)

npm install
npm start

That is enough to use it nightly. Leave it running, kill it in the morning.

Test the global CLI locally before publishing:

npm link
cafx

Build the installers

The project is wired for electron-builder. Build each installer on its own platform (Apple's tooling makes a real .dmg only on macOS, and the Windows installer wants Windows or Wine).

# on your Mac  ->  release/Caffeinatrix-1.0.0.dmg
npm run dist:mac

# on your PC   ->  release/Caffeinatrix Setup 1.0.0.exe
npm run dist:win

Output lands in release/. The Windows build is a standard NSIS installer (pick the folder, gets a desktop + Start Menu shortcut). The Mac build is a drag-to-Applications .dmg. App icons are already generated in build/ (icon.icns, icon.ico, icon.png), so the installed app and desktop shortcut carry the coffee-cup logo.

Unsigned builds will trip Gatekeeper on macOS and SmartScreen on Windows the first time. For personal use just right-click open (Mac) or choose "More info -> Run anyway" (Windows). Code signing is optional and only matters if you distribute it.

Make it yours

Everything lives in renderer.js near the top:

const FONT_SIZE = 18; // glyph size
const HEAD = "#cfffd0"; // leading glyph color
const BODY = "#00ff41"; // trail color (classic matrix green)
const FPS = 26; // frame cap (lower = cooler/quieter laptop)

Drop FPS for an even calmer overnight burn, bump FONT_SIZE for chunkier glyphs, or swap the greens for amber if you want the old-terminal look. The glyph set is half-width katakana plus digits; edit the GLYPHS builder to change the alphabet.

Logo

assets/logo.svg is the source of truth: a coffee cup whose steam is the code, brewed in matrix green. Regenerate the raster icons any time with python3 build_logo.py followed by the icon export in this repo's history.

Publish to npm

Maintainer workflow. You need an npm account and a one-time login on the machine that publishes:

npm login

Bump version in package.json before each release (npm rejects duplicate versions). Then:

make npm-pack      # optional — see exactly what ships in the tarball
make npm-publish   # npm publish --access=public

Or without Make:

npm pack --dry-run
npm publish --access=public

The published npm package is @jameymcelveen/cafx; the app window and installers still say Caffeinatrix. The tarball includes the Electron app and the cafx CLI (bin/cafx.js). electron-builder installers stay a separate local build (make dist-mac / make dist-win); they are not uploaded to npm.

Package page: npmjs.com/package/@jameymcelveen/cafx

License

MIT. Do whatever you like with it.