Dear Debian fonts task force and reproducible task force,FontForge is discussing merging support for SOURCE_DATE_EPOCH & Co in order to support the reproducible creation of fonts files.
Could you please have a look the pull request [1] and chime in if you thing that it looks correct or if something has been overlooked?
Regards, [1] https://github.com/fontforge/fontforge/pull/3176 -- Gioele Barabucci <gioele@svario.it>