Bastardica: a browser tool for splicing fonts into deliberately cursed typefaces

Bastardica is a web-based type foundry for making intentionally mangled fonts, mixing, stretching, and squishing existing typefaces into hybrids with names like Times New Bastard. Each result exports as a standard OpenType file, and the character swapping is implemented as a contextual ligature substitution registered across every script — so browsers, design apps, and print pipelines apply the effect by default wherever OpenType shaping runs. If a font appears unchanged, the culprit is usually ligatures being disabled in the host application.

The tool runs entirely client-side using Pyodide and fontTools, so no uploaded fonts leave the user’s browser. When three or more fonts are blended, their glyph strides eventually collide (every 5th and every 7th overlap on every 35th glyph, for example); the first font takes precedence in conflicts, and the maker recommends prime-number strides to minimize collisions, plus Y-offset and scale tweaks to align mismatched glyphs.

The main practical caveat is licensing: combining two fonts creates a derivative work, so anyone using a bastard font commercially must clear the licenses of both source faces. Bastardica adds no terms of its own and requests only optional credit.