Am Samstag, dem 10.09.2022 um 02:33 +0200 schrieb Maxime Devos: > The docstring is nice, but with documentation, I meant the manual, > presumably in ‘(guix)package Reference’, maybe also in the packaging > tutorial in the cookbook. I don't see the current practice documented, so I think we're actually good on this front. > Also, something I forgot: performance.  sanitize-inputs is called for > every package, and the change adds additional memory allocations (due > to the use of 'filter'), is there an observable performance impact > (maybe "GUIX_PROFILING=gc time guix refresh -l pkg-config" would be a > good test)?  If there is, some optimisations may be in order Looking at the numbers below Garbage collection statistics: heap size: 212.66 MiB allocated: 739.15 MiB GC times: 20 time spent in GC: 5.30 seconds (65% of user time) real 0m3,606s user 0m8,140s sys 0m0,109s Garbage collection statistics: heap size: 276.29 MiB allocated: 1292.10 MiB GC times: 28 time spent in GC: 10.48 seconds (64% of user time) real 0m11,638s user 0m16,422s sys 0m0,308s it does appear that this increases times by a factor of two. Use of filter! instead of filter brings only marginal benefits. I'll check if we could instead simply ignore unspecified? values when collecting the inputs – that would allow the natural use of (when) and (unless). Cheers