Space Invaders

A small cross-platform desktop Space Invaders game written in Go. The game renders every frame on the Go side and shows it in a native webview window — no game engine, no GUI toolkit, and (as of v0.3.0) no web server either: the window talks straight to Go through webview_go's Bind.

!Space Invaders

The story behind the app, and a walkthrough of how it was built, is in the original article: Create a simple cross-platform desktop game with Go.

!Space Invaders on a Mac

How to play

| Key | Action | |---|---| | s | Start the game, and restart after game over | | ← / → | Move the laser cannon (hold to keep moving) | | Space | Fire | | p | Pause / resume | | q | Quit to the title screen while playing; quit the app from the title screen |

Aliens in the top row are worth 30 points, the middle row 20 and the bottom row 10. You have multiple lives per game, and the aliens come in waves — clear one and a faster, tougher wave marches in behind it. Destructible shields give you cover from alien bombs, and a bonus UFO occasionally crosses the top of the screen for extra points. The game keeps a running high score across plays. It's over for good when you lose your last life.

How it works

The whole game is one Go binary with no web server and no browser involved — just a native OS webview window bound directly to Go functions:

1. The game loop (invaders.go and friends), running in its own goroutine, owns all game state. Each tick it moves sprites, checks collisions, draws everything onto an image with gift, and encodes it as a PNG data URI, tagged with an incrementing sequence number.
2. A native webview window (main.go, via webview_go) hosts a tiny embedded HTML page (public/html/game.html) and binds three Go functions straight into its JavaScript global scope with w.Bind:

1. Assets are embedded (assets.go, via //go:embed public) — the sprite sheet, backgrounds, sounds and the HTML page all live inside the compiled binary, decoded on demand. That means go run . works from a source checkout, and a distributed binary or app bundle needs no public/ folder alongside it.

.
├── main.go              webview window, Bind wiring, quit handling
├── assets.go            //go:embed public + asset accessors (images, HTML, sounds)
├── sound.go             sound loading and playback
├── invaders.go          Sprite type, collide, createAlien
├── game.go              Game state, startNewGame/startNextWave, step() and the game loop
├── frame.go             frame encoding (createFrame) and publishing (currentFrame)
├── input.go             keyDown/keyUp and the thread-safe input snapshot
├── render.go            render(): draws the current Game state to an image
├── hud.go               printLine (bitmap text) and drawHUD (score/lives)
├── shield.go            destructible bunker bitmap logic
├── highscore.go         high score load/save (JSON in the user config dir)
├── invaders_test.go     unit tests for Sprite/collide
├── game_test.go         unit tests for game state and step()
├── render_test.go       snapshot rendering tests (INVADERS_SNAPSHOT_DIR)
├── shield_test.go       unit tests for shields
├── highscore_test.go    unit tests for high score persistence
├── public/              game HTML page, sprite sheet, backgrounds, sounds
├── invaders.app/        macOS app bundle
└── build-macOS          builds the macOS app bundle

Requirements

• Go 1.26 or later. The module pins toolchain go1.26.8, which Go downloads automatically if needed.
• cgo (CGO_ENABLED=1) and a C/C++ compiler, since webview wraps the operating system's own web view:

Build and run

All assets are embedded in the binary, so there's nothing to copy alongside it — go run . works straight from a checkout:

go run .

To build a standalone binary:

go build -o invaders
./invaders

On Windows, hide the console window with:

go build -ldflags="-H windowsgui" -o invaders.exe

macOS app bundle

./build-macOS
open invaders.app

This just builds the binary into invaders.app/Contents/MacOS — since assets are embedded, the bundle needs nothing else alongside it.

A prebuilt Apple Silicon bundle is attached to each release. It is unsigned, so right-click it and choose Open the first time.

Tests

go test ./...

Screenshots

The start screen on Windows:

!Space Invaders on Windows

Playing on Windows:

!Space Invaders game on Windows

Credits

• Sound effects from Classics United.
• Thanks to Ibrahim Wu, who helped debug the app on Windows and found the MSHTML frame caching problem.
• Thanks to Serge Zaitsev for the original webview package, and to the maintainers of webview_go and gopxl/beep.