The latest articles on DEV Community by mimi chat (@mimi_chat_b3bf7a39a962a82). https://dev.to/mimi_chat_b3bf7a39a962a82 https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4205435%2F98d46a60-aa6b-44b8-afe7-a98ea95ebe64.jpg https://dev.to/mimi_chat_b3bf7a39a962a82 en mimi chat Sat, 24 Oct 2026 20:21:59 +0000 https://dev.to/mimi_chat_b3bf7a39a962a82/running-a-21k-line-php-game-at-60-fps-in-the-browser-with-webassembly-2cd3 https://dev.to/mimi_chat_b3bf7a39a962a82/running-a-21k-line-php-game-at-60-fps-in-the-browser-with-webassembly-2cd3 <p>I wanted to see how far PHP in WebAssembly could go. So I wrote a fan remake of <strong>Sonic the Hedgehog (Master System)</strong> entirely in PHP, about 21k lines, and made it run both natively and in the browser.</p> <p>👉 <strong>Play it, no install: <a href="https://sonic.mimichat.fr" rel="noopener noreferrer">https://sonic.mimichat.fr</a></strong> (desktop and mobile)</p> <h2> How PHP runs in a browser </h2> <p>PHP 8.3 is compiled to WebAssembly with Emscripten, together with an SDL2 extension for PHP. A small C glue starts PHP (<code>php_embed_init</code>), runs the game, then plugs into the browser loop: on every <code>requestAnimationFrame</code>, one tick of the game's ReactPHP event loop.</p> <p>The tricky part: ReactPHP's <code>Loop::run()</code> is blocking, and a browser can't allow that. So the page queues a <code>futureTick</code> that stops the loop right after its first turn, and the C glue then advances it one tick at a time. PHP is never shut down between frames (<code>php_embed_shutdown()</code> is never called): every object and SDL resource stays in memory, the whole game state lives across frames.</p> <p>SDL2's Emscripten port renders to WebGL and plays sound through Web Audio. Saves go to IndexedDB (IDBFS).</p> <p>One lesson learned: use <strong>one</strong> browser loop only. A second <code>setTimeout(0)</code> loop ran the game between frames too, saturating the main thread so that input and audio came last.</p> <h2> Online multiplayer, up to 6 players </h2> <p>Race, capture the flag, rings, deathmatch. Browsers talk directly over WebRTC; a relay written in PHP handles rooms and signaling, with coturn for difficult networks. A player on the native desktop version can join the same room through the relay. The network layer is its own library: php-wasm-network.</p> <h2> The website </h2> <p>Symfony 8.1 on FrankenPHP: live rooms, stats, faithful replays of every game, and editors for levels, tiles (drawing and collisions), sprites, sounds and music. A published level is playable in the game right away. Visitors appear live as little Sonics running across the page, through Mercure subscription events.</p> <h2> Try it </h2> <ul> <li>Play: <a href="https://sonic.mimichat.fr" rel="noopener noreferrer">https://sonic.mimichat.fr</a> </li> <li>Build a level in the editor and play it in-game</li> <li>Create a private room and send the link to a friend</li> </ul> <p>Code: <a href="https://github.com/davidnurdin/sonicGamePhp" rel="noopener noreferrer">sonicGamePhp</a> (game), <a href="https://github.com/davidnurdin/php-wasm-sdl" rel="noopener noreferrer">php-wasm-sdl</a> (PHP + SDL in WASM), <a href="https://github.com/davidnurdin/php-wasm-network" rel="noopener noreferrer">php-wasm-network</a> (networking).</p> <p>It's a non-commercial fan project, Sonic belongs to SEGA. Questions about PHP in WASM are welcome in the comments!</p> php webassembly gamedev showdev