Every Byte Counts: Coding Under the 64K Ceiling

July 31, 2026

A tribute to the vanished discipline of squeezing software into kilobytes, inspired by how Doug McIlroy fit a 250kB dictionary into 64kB of RAM for the Unix spell checker.

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Type letters to fill the puzzle. Use arrow keys to move, Space to switch between across and down, Tab for the next clue, and Backspace to erase.

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