I spent many hours in college playing what I consider to be one of the best 2d arcade shooters out there: Kobo Deluxe, by David Olofson. As an experiment, I asked Claude Opus to port it to WASM so I could play it in my browser.

The game was written in C/C++ against SDL 1.2, so getting it onto the web meant compiling it to WebAssembly with Emscripten. The game's own code is unchanged. It runs on sdl12-compat, which implements the SDL 1.2 API on top of SDL2, and SDL2 handles graphics, sound and input in the browser.

A few notes:

• Click the game to start it, because browsers won't play sound until you do.
• Arrow keys move, Ctrl or Shift fires, and Esc brings up the menu.
• Your scores and settings are saved in your browser.

Kobo Deluxe is free software under the GPL. All credit for the game goes to David Olofson and the other Kobo contributors. The source for this web version, including the build script, is at github.com/kyptin/kobodeluxe-web.