The open‑source project Souls Only delivers a font that hides readable text behind a noisy character stream. When a user types on a standard US‑QWERTY keyboard, the firmware emits four ASCII symbols for each glyph; the font’s GSUB liga rules collapse them back into legible letters at render time. Copy‑pasting the invisible raw data yields only plain gibberish.

The implementation separates the character stream from the glyph stream by assigning each printable symbol two random half‑codes drawn from a pool of ASCII homophones. Four characters form one displayed glyph, and shared left‑half fragments reduce file size while leaving a faint seam on certain stems. The variable‑font version adds a custom REVL axis that scatters or restores the text depending on its value.

All font files are distributed under the SIL Open Font License 1.1, while the accompanying encoder, decoder and QMK keyboard firmware carry an MIT license. Installation works on macOS, Windows or via @font‑face on the web; the font only decodes streams generated by the provided tools. Souls Only functions as a statement device rather than a security mechanism.