1. Summarise the issue (what were doing, what went wrong?)
The ~/.darcs directory is used for configuration files
2. What behaviour were you expecting instead?
XDG spec should be followed:
http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
The configuration should be placed in ~/.config/darcs by default while
cache should be in ~/.cache/darcs etc.
3. What darcs version are you using? (Try: darcs --exact-version)
2.8.5
4. What operating system are you running?
GNU/Linux

Agreed. I think for cache we do this now (2.10). For config, ~/.darcs is
still used IIRC.