I tried to bring this `TimeFunc` on the `ParserOptions`, then pass it in the `Claims` But I just saw a recent retraction of something very similar. https://github.com/golang-jwt/jwt/pull/184 So, I would believe you will not accept a PR like mine until v5, but having the `TimeFunc()` local makes more sense for testing https://github.com/jsgoupil/jwt/commit/a6c0c037dc35f72e1afc9a9628ae10837d4cc5bb I hope you can consider this bug for a future release.