> It would be trivial to have a similar mechanism for `bash_rc.d` which allows for a pluggable system to extend and modify your bash.
There is /etc/profile.d/ which serves much the same purpose for login shells, though PS1 is normally a non-exported shell variable so it wouldn't be inherited. You can configure most other aspects of the shell this way, however. And there is also /etc/bash.bashrc which is read before ~/.bashrc, though it doesn't provide a convenient directory for drop-in scripts by default the way /etc/profile does. It would be trivial to add that if desired. (All based on Debian; YMMV.)
There is /etc/profile.d/ which serves much the same purpose for login shells, though PS1 is normally a non-exported shell variable so it wouldn't be inherited. You can configure most other aspects of the shell this way, however. And there is also /etc/bash.bashrc which is read before ~/.bashrc, though it doesn't provide a convenient directory for drop-in scripts by default the way /etc/profile does. It would be trivial to add that if desired. (All based on Debian; YMMV.)