Older Makefiles (prior to DESTDIR's introduction, e.g.) may not use DESTDIR to specify the installation target. For example, redis uses PREFIX instead (https://github.com/antirez/redis/blob/unstable/src/Makefile). This leads to very simple wrappers for this kind of support (e.g., https://github.com/kyrofa/nextcloud-snap/blob/master/parts/plugins/x-redis.py) when it seems like something that should be specifiable in the yaml. Technically, PREFIX could be specified as a make-parameter, but the value needs to be settable to "self.installdir" as defined in the make plugin itself; but this value is not exposed in any way that I've found. So there are two solutions (both of which might be worth implementing): 1) Allow the specific Makefile environment variable for installation target to be specifiable (default would be DESTDIR?) 2) Expose the make plugin's internal variables (e.g., self.installdir) as YAML variables. This will need some consideration so it's clear to end users these are snap-specific variables.