Updated September 14, 2026

Credits

Heft builds on open work by other people. Here is what was used, under which licence, and what changed.

Exercise illustrations

Most exercise drawings are adapted from workout-guide by Bryl Lim, © 2026 Bryl Lim; seventy-six of its first poses are traced from Everkinetic artwork. Heft traced thirty more drawings from Everkinetic poses in the same style. Both sources are licensed under CC BY-SA 4.0. Heft recoloured and simplified them: fills recoloured, paths rounded and re-encoded, metadata removed. The adapted drawings are published under the same licence at heft.pstepanov.dev/exercises, one file per exercise.

Exercise list

The built-in exercises (names, muscles, equipment and how each is tracked) are derived from workout-guide's manifest, © 2026 Bryl Lim, under the MIT License. The exercises Heft added on top carry its own descriptions.

Muscle map

The body map is react-native-body-highlighter, under the MIT License.

Icons and type

Icons from Tabler Icons, under the MIT License. Instrument Sans, under the SIL Open Font License. Assistant logos come from Simple Icons (CC0) and remain their owners' trademarks. The hand drawings come from an open-source illustration library in the Figma Community.