I compiled proj (also known as proj.4) from sources on Ubuntu (https://github.com/OSGeo/proj.4.git).
I now wonder why is proj version dated in the future?
E.g.:
$ proj
Rel. 6.0.0, March 1st, 2019
Edit:
Same for proj version 6.1.0, which I freshly updated from git sources:
$ proj
Rel. 6.1.0, September 1st, 2019