+## The `sbuild' tool sets a fake `home' directory which doesn't exist. This
+## breaks ASDF, which wants to write FASL files into `~/.cache/common-lisp/'.
+## Set an explicit cache directory for it, and clear away the FASL cache
+## directory on clean.
+export XDG_CACHE_HOME := $(shell pwd)/debian/build/cache
+override_dh_auto_clean:
+ dh_auto_clean
+ rm -rf debian/build/cache
+