And, in the past, I'm not aware that the availability of tools in the Debian ecosystem has been a strong determining factor in the choice of tooling for CPython.  In particular, I'm not aware of any tool in the Debian package ecosystem that would solve the problem blurb solves, much less in exactly the way blurb does it.  In fact, there was no existing tool anywhere that solved the *exact* problem we had.  So we wrote our own.  And obviously a newly written tool isn't going to have a Debian package.  So your argument "you should only choose external dependencies that already have Debian packages" isn't going to work either, as that is not and has never been a rule in CPython development.

I'm pretty sure blurb is going to remain a part of the CPython toolchain.  The slight inconvenience you have registered here is so far not enough of a negative vote to outweigh the groundswell of positive support.  I suggest you redirect your energies to solving the problem rather than complaining about it.