On Wed, Jul 01, 2020 at 05:53:31PM +0100, pkill9 wrote: > For example, `guix build --with-source=youtube-dl=blahblah mpv` builds > mpv normally, after giving a message: guix build: warning: > transformation 'with-source' had no effect on mpv@0.32.0 > From 'guix build --help:' --with-source=SOURCE use SOURCE when building the corresponding package --with-input=PACKAGE=REPLACEMENT replace dependency PACKAGE by REPLACEMENT I think what you're looking for is more of: guix build --no-grafts mpv --with-input=youtube-dl=$(guix build --no-grafts youtube-dl --with-source=https://github.com/ytdl-org/youtube-dl/releases/download/2020.06.16/youtube-dl-2020.06.16.tar.gz) This didn't work for me though, I got: guix build: error: /gnu/store/9ncacjhzwlchpr1y5fd8ahdq59dsya20-youtube-dl-2020.06.16: unknown package -- Efraim Flashner אפרים פלשנר GPG key = A28B F40C 3E55 1372 662D 14F7 41AA E7DC CA3D 8351 Confidentiality cannot be guaranteed on emails sent or received unencrypted