What is font-harness?

Cheonjiin is an experimental Korean (Hangul) font that pushes the original design principles behind Hunminjeongeum, the historical document that introduced the Korean writing system, to an extreme. The idea behind the font is that every one of the 11,172 possible Hangul syllable blocks, both vowels and consonants, can be built from just three basic shapes: a circle representing sky, a horizontal bar representing earth, and a vertical bar representing people. No curved strokes and no diagonal strokes appear anywhere in the font. To install it, a user downloads the finished font file, a .ttf covering all 11,172 characters, and installs it like any other system font, for example through the macOS font manager. The design rules are strict and geometric. Every letter shape is built only from a solid circle, a horizontal bar, and a vertical bar. Vowel dots are solid circles of a fixed size, smaller when a final consonant is present, the circle-based consonants use a fixed ring width, bar thickness is constant, and every coordinate snaps to a shared grid. Diagonal strokes in certain consonants are redrawn as right-angle shapes instead. Rather than drawing each of the thousands of syllables by hand, the font is generated by a system: 67 defined letter components are combined by a composition engine. Scripts convert those component definitions into SVG outlines for whole syllables, or for the full character set at once, and a separate build step compiles the resulting SVGs into a TTF font file. Because each letter component is defined once, fixing a single component automatically updates every syllable that uses it. The font itself was built using a multi-agent Claude Code setup, with separate agents handling roles like structural analysis, concept design, letter design for different syllable positions, composition engineering, specimen creation, font engineering, and quality review, organized through a set of custom skills. The font is released under the SIL Open Font License 1.1, a free license that allows use, modification, and redistribution, including commercial use. Modified versions must also use the OFL license, but they cannot use the name Cheonjiin, since that name is reserved.