Building a World Map with only 500 bytes
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4th July 2026 - Link Blog
Building a World Map with only 500 bytes (via) Iwo Kadziela (assisted by Codex) figured out a way to generate a credible ASCII world map using 445 bytes of data:
The key trick is to use deflate compression, which is then wired together using this neat snippet of JavaScript. I didn't know you could use fetch() with data: URIs like this:
fetch('data:;base64,1ZpLsgIxCEXnrM...==').then( r => r.body.pipeThrough(new DecompressionStream('deflate-raw')) ).then( s => new Response(s).text() ).then( t => b.innerHTML = '' + t )
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This is a link post by Simon Willison, posted on 4th July 2026.
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