Hi Guix, I was trying to use `xdot` to view to output of `guix graph` (`guix graph bash | xdot -`). However, it crashed instantly with the following stack trace: > dot: No such file or directory > Traceback (most recent call last): >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/bin/.xdot-real", > line 33, in >     sys.exit(load_entry_point('xdot==1.3', 'gui_scripts', 'xdot')()) >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/lib/python3.10/site-packages/xdot/__main__.py", > line 80, in main >     win.set_dotcode(sys.stdin.buffer.read()) >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/lib/python3.10/site-packages/xdot/ui/window.py", > line 712, in set_dotcode >     if self.dotwidget.set_dotcode(dotcode, filename): >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/lib/python3.10/site-packages/xdot/ui/window.py", > line 148, in set_dotcode >     if self._set_dotcode(dotcode, filename, center=center): >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/lib/python3.10/site-packages/xdot/ui/window.py", > line 134, in _set_dotcode >     xdotcode = self.run_filter(dotcode) >   File > "/gnu/store/r9mrqfpci65hsypgm7r5kpzxlm6fcd1l-xdot-1.3/lib/python3.10/site-packages/xdot/ui/window.py", > line 129, in run_filter >     return xdotcode > UnboundLocalError: local variable 'xdotcode' referenced before assignment Using `guix time-machine` I was able to identify the regression commit as 2aeb9faa421635c0531d96658414e5bf288a3142 (when Ludo' updated it to 1.3). Using `xdot` within the time machine inside the parent commit works. I've cc'd Ludo' and hopefully we can fix this! Warmly, Ada