I’ve just released Tepl 5.99.1, it’s an unstable/development version towards Tepl 6.
The thing is, Tepl 6.00.0 has already been released last year. Note the double zeros, which was a mistake, unfortunately.
So, the plan is to release a Tepl 6.0.1 version once the 5.99 development cycle is finished (the project was “frozen” last year, and has now been thawed).
Tepl 6.0.1 will be backward-compatible with Tepl 6.00.0. Normally no further API breaks are planned. If there is an additional API break compared to 6.00.0, then I will have no choice to do a Tepl 7 release.
Note, no need to keep old Tepl major versions around in the distribution if there are no reverse deps. (The old name for Tepl was Gtef, so the same applies to Gtef as well).
(And Tepl is no longer a GNOME core dependency, so it is more independent).