bug#70954: No 'guix pull' substitutes for foreign distros?

[Nigko Yerden <nigko.yerden@gmail.com>]

Hello Guix!

I have two systems: first (A) is a full Guix system and second (B) is a 
foreign distribution with Guix package manager installed onto. I have 
noticed when I'm performing 'guix pull' system B always build 'guix 
pull' derivations by itself while system A most often just download 
substitutes for them. The latter, of course, is much faster.

Here is how it looks on system B (commit 
014875b29e68da6357a5323e6dd1eaa74a05b753):

$ guix pull
Updating channel 'guix' from Git repository at 
'https://git.savannah.gnu.org/git/guix.git'...
Authenticating channel 'guix', commits 9edb3f6 to 08360a2 (781 new 
commits)...
Building from these channels:
   guix      https://git.savannah.gnu.org/git/guix.git	08360a2
substitute: updating substitutes from 
'https://mirrors.sjtug.sjtu.edu.cn/guix'... 100.0%
26,4 MB will be downloaded
....
The following derivations will be built:
   /gnu/store/q9b8yr9452im7mmah1cfk2dpy44y755v-profile.drv
   /gnu/store/87avc5s6q4xq1rdk26cnlviai7hfjzi0-inferior-script.scm.drv
   /gnu/store/saji8f542jbrmj6315lxrgmgjdgrzlx4-guix-08360a2cd.drv
   /gnu/store/3j2xd5l3q0s1jf9798fr4s3k3ky5fw07-guix-manual.drv
   /gnu/store/42bwpkmcv6jsdzhsxc0pwc13k1fgxh25-guix-08360a2cd-modules.drv

/gnu/store/2cl0dr63d900v6406hs10qgjsp7iaysi-guix-packages-base-modules.drv
   /gnu/store/j8av01zjcx9kimjm0yrdrkhmiba7wwmj-guix-packages-base.drv
   /gnu/store/a7w5hbq6kppl90838b3iwpgn4v93jv75-guix-extra.drv
   /gnu/store/gd8lqzj70wx5qgx39lnh3lh4g5slln5g-guix-core-source.drv
   /gnu/store/2f0z0x4nqpwgwmrk5qs7ka0p3y2a2gny-config.scm.drv
   /gnu/store/6r0k3wg5bcjnjdjlx8rvxr2q3izyhgvh-guix-system-tests-modules.drv
   /gnu/store/7pmrsz3mlnhiggm3pz99wiyrddahl9mb-guix-system-tests.drv
   /gnu/store/3jwjfb0rjxsvv4xy0m65db0nmbg56nx7-guix-cli.drv
   /gnu/store/87yna60fdd0gv70nb4svqvxq8br4cbm6-guix-cli-core.drv
   /gnu/store/b28ayyn4jqfz5dbgcshh5gmayzms65wj-guix-system.drv
   /gnu/store/x5x97w98q16myzx3rfik1gs06n1vbccr-guix-packages.drv
   /gnu/store/sxhm9vii5lwig55vjpc4jz639r9ygdyx-guix-home.drv
   /gnu/store/7i2z4b2imjxc0qd5kgis9c045ybq0wwy-guix-system-modules.drv
   /gnu/store/f3qxxs77klhk0q8bvsxdly1xr147wb9s-guix-cli-modules.drv
   /gnu/store/fl6m42fdnykhd5drv42s1zn5x18vbiy9-guix-extra-modules.drv
   /gnu/store/h7ynn7s9p8ywd5s2s4g43l6rgkqdidqd-guix-home-modules.drv
   /gnu/store/i0qnblii1as7yk2pz3vvvfd9mh28fdzv-guix-config-modules.drv
   /gnu/store/m02vi15w4chc27kgrf2x55riacsl20gc-guix-config-source.drv
   /gnu/store/6z80pzmm18nmbmblk9mh2vjl1hvdzm02-config.scm.drv
   /gnu/store/jilxlihmy07h9xhr1pbxw5i01b4l1js1-guix-cli-core-modules.drv
   /gnu/store/ng76j3d6m66w7jfk0gds9204zp4l727p-guix-packages-modules.drv
   /gnu/store/znffqlp69qjbvzpnjvvfmpc4fq6q9b8w-guix-core-modules.drv
   /gnu/store/qxaqgq36bg5mi210yflrg31hz3nxjfb3-guix-command.drv
   /gnu/store/as05nvh2dq4s0pb0lxkmcyf407c7wjcm-guix-module-union.drv
   /gnu/store/qxsz62r8giy0hf8qqzzv8f35g6470kcj-guix-daemon.drv
   /gnu/store/za0rf8ypn7v1a9a7cc7fmnnh7pig5580-guix-misc.drv
   /gnu/store/pf1h4mhpp6qhvixzr4172v81wqy1wj1x-inferior-script.scm.drv
   /gnu/store/3aci63l4yq7i9jh4v55f0lyk3hji8z1w-inferior-script.scm.drv
   /gnu/store/3kjkjx8fayv97p48rgdmi51mlwx6lb7c-profile.drv

3,0 MB will be downloaded
  module-import-compiled  128KiB        57KiB/s 00:02 
▕██████████████████▏ 100.0%
  guix-config  4KiB                    647KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-core  1.8MiB                    418KiB/s 00:04 
▕██████████████████▏ 100.0%
  guix-translated-texinfo  1.7MiB      971KiB/s 00:02 
▕██████████████████▏ 100.0%
  module-import-compiled  8KiB          13KiB/s 00:01 
▕██████████████████▏ 100.0%
  module-import-compiled  47KiB         88KiB/s 00:01 
▕██████████████████▏ 100.0%
  module-import-compiled  66KiB         20KiB/s 00:03 
▕██████████████████▏ 100.0%
  module-import-compiled  97KiB          6KiB/s 00:17 
▕██████████████████▏ 100.0%
  module-import-compiled  54KiB          8KiB/s 00:07 
▕██████████████████▏ 100.0%
building /gnu/store/2f0z0x4nqpwgwmrk5qs7ka0p3y2a2gny-config.scm.drv...
building /gnu/store/6z80pzmm18nmbmblk9mh2vjl1hvdzm02-config.scm.drv...
applying 9 grafts for gd-2.3.2 ...
applying 5 grafts for gts-0.7.6 ...
building 
/gnu/store/m02vi15w4chc27kgrf2x55riacsl20gc-guix-config-source.drv...
applying 19 grafts for graphviz-minimal-7.0.1 ...
building 
/gnu/store/i0qnblii1as7yk2pz3vvvfd9mh28fdzv-guix-config-modules.drv...
building /gnu/store/gd8lqzj70wx5qgx39lnh3lh4g5slln5g-guix-core-source.drv...
building /gnu/store/za0rf8ypn7v1a9a7cc7fmnnh7pig5580-guix-misc.drv...
building 
/gnu/store/znffqlp69qjbvzpnjvvfmpc4fq6q9b8w-guix-core-modules.drv...
building /gnu/store/a7w5hbq6kppl90838b3iwpgn4v93jv75-guix-extra.drv...
building 
/gnu/store/87avc5s6q4xq1rdk26cnlviai7hfjzi0-inferior-script.scm.drv...
building 
/gnu/store/fl6m42fdnykhd5drv42s1zn5x18vbiy9-guix-extra-modules.drv...
building 
/gnu/store/j8av01zjcx9kimjm0yrdrkhmiba7wwmj-guix-packages-base.drv...
building 
/gnu/store/pf1h4mhpp6qhvixzr4172v81wqy1wj1x-inferior-script.scm.drv...
building /gnu/store/87yna60fdd0gv70nb4svqvxq8br4cbm6-guix-cli-core.drv...
building 
/gnu/store/2cl0dr63d900v6406hs10qgjsp7iaysi-guix-packages-base-modules.drv...
building 
/gnu/store/jilxlihmy07h9xhr1pbxw5i01b4l1js1-guix-cli-core-modules.drv...
building /gnu/store/x5x97w98q16myzx3rfik1gs06n1vbccr-guix-packages.drv...
applying 3 grafts for libfontenc-1.1.4 ...
building 
/gnu/store/ng76j3d6m66w7jfk0gds9204zp4l727p-guix-packages-modules.drv...
building /gnu/store/b28ayyn4jqfz5dbgcshh5gmayzms65wj-guix-system.drv...
applying 8 grafts for mkfontscale-1.2.2 ...
building /gnu/store/sxhm9vii5lwig55vjpc4jz639r9ygdyx-guix-home.drv...
building 
/gnu/store/7i2z4b2imjxc0qd5kgis9c045ybq0wwy-guix-system-modules.drv...
building /gnu/store/3jwjfb0rjxsvv4xy0m65db0nmbg56nx7-guix-cli.drv...
building 
/gnu/store/h7ynn7s9p8ywd5s2s4g43l6rgkqdidqd-guix-home-modules.drv...
building /gnu/store/f3qxxs77klhk0q8bvsxdly1xr147wb9s-guix-cli-modules.drv...
building 
/gnu/store/7pmrsz3mlnhiggm3pz99wiyrddahl9mb-guix-system-tests.drv...
applying 2 grafts for mkfontdir-1.0.7 ...
building 
/gnu/store/6r0k3wg5bcjnjdjlx8rvxr2q3izyhgvh-guix-system-tests-modules.drv...
applying 6 grafts for texinfo-6.8 ...
building 
/gnu/store/42bwpkmcv6jsdzhsxc0pwc13k1fgxh25-guix-08360a2cd-modules.drv...
building /gnu/store/3j2xd5l3q0s1jf9798fr4s3k3ky5fw07-guix-manual.drv...
building 
/gnu/store/as05nvh2dq4s0pb0lxkmcyf407c7wjcm-guix-module-union.drv...
building /gnu/store/qxaqgq36bg5mi210yflrg31hz3nxjfb3-guix-command.drv...
building /gnu/store/qxsz62r8giy0hf8qqzzv8f35g6470kcj-guix-daemon.drv...
building /gnu/store/saji8f542jbrmj6315lxrgmgjdgrzlx4-guix-08360a2cd.drv...
building CA certificate bundle...
listing Emacs sub-directories...
building fonts directory...
building directory of Info manuals...
...


And there how it looks on system A (the same commit 
014875b29e68da6357a5323e6dd1eaa74a05b753):
Updating channel 'guix' from Git repository at 
'https://git.savannah.gnu.org/git/guix.git'...
Authenticating channel 'guix', commits 9edb3f6 to 08360a2 (781 new 
commits)...
Building from these channels:
   guix      https://git.savannah.gnu.org/git/guix.git	08360a2
26,4 MB will be downloaded
...
substitute: updating substitutes from 
'https://mirrors.sjtug.sjtu.edu.cn/guix'... 100.0%
...
The following derivations will be built:
   /gnu/store/pfs471chzsnwyl3zdkz3wkzl5gpsqchm-profile.drv
   /gnu/store/87avc5s6q4xq1rdk26cnlviai7hfjzi0-inferior-script.scm.drv

/gnu/store/1mwhp5crimgvqd4jmlfsj3017yk8vxsv-guix-packages-base-modules.drv
   /gnu/store/4bay72mqflnhx3382gy5lmcjiv0k673s-guix-system-tests-modules.drv
   /gnu/store/5dsx6hxbrsy8iljmz6sjn08f1c9q5zi9-guix-system-modules.drv
   /gnu/store/j33qgaybzml6fbfldw5nljgq4haxd34f-guix-cli-core-modules.drv
   /gnu/store/rzwb58zr3mnz5pff4v0581nr8bhh4bj5-guix-cli-modules.drv
   /gnu/store/yhv9fr3rzlnk8dmgiwz73rjz6xalip94-guix-extra-modules.drv
   /gnu/store/hmcds0yp3bxl8y8gaf6a42jfipvqgsii-guix-daemon.drv
   /gnu/store/x91k63vwwj6mahn804hjg5n9xzsjj4sn-guix-command.drv
   /gnu/store/pf1h4mhpp6qhvixzr4172v81wqy1wj1x-inferior-script.scm.drv
   /gnu/store/2x3s1sx169y9lk9wdnz8p21c88jr8jkd-profile.drv
   /gnu/store/mkq51lalsi9vy94afskmi92854sx1cxm-inferior-script.scm.drv

70,0 MB will be downloaded
substitute: updating substitutes from 
'https://mirrors.sjtug.sjtu.edu.cn/guix'... 100.0%
...
  module-import-compiled  128KiB      43.7MiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-cli  315KiB                      27KiB/s 00:12 
▕██████████████████▏ 100.0%
  guix-cli-core  922KiB                 21KiB/s 00:44 
▕██████████████████▏ 100.0%
  guix-cli-modules  260B                56KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-cli-core-modules  261B           46KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-extra  2.8MiB                    10KiB/s 04:45 
▕██████████████████▏ 100.0%
  guix-manual  5.2MiB                   13KiB/s 06:58 
▕██████████████████▏ 100.0%
  guix-extra-modules  260B              61KiB/s 00:00 
▕██████████████████▏ 100.0%
  module-import-compiled  66KiB         34KiB/s 00:02 
▕██████████████████▏ 100.0%
  guix-packages-base  17.4MiB          777KiB/s 00:23 
▕██████████████████▏ 100.0%
  guix-system  7.9MiB                  702KiB/s 00:12 
▕██████████████████▏ 100.0%
  guix-packages-base-modules  268B     140KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-system-modules  261B            101KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-system-tests  921KiB            368KiB/s 00:03 
▕██████████████████▏ 100.0%
  module-import-compiled  54KiB         69KiB/s 00:01 
▕██████████████████▏ 100.0%
  guix-system-tests-modules  263B       57KiB/s 00:00 
▕██████████████████▏ 100.0%
building 
/gnu/store/87avc5s6q4xq1rdk26cnlviai7hfjzi0-inferior-script.scm.drv...
applying 8 grafts for mkfontscale-1.2.2 ...
  guix-08360a2cd-modules  31.2MiB      1.9MiB/s 00:17 
▕██████████████████▏ 100.0%
building 
/gnu/store/pf1h4mhpp6qhvixzr4172v81wqy1wj1x-inferior-script.scm.drv...
  guix-module-union  2KiB              149KiB/s 00:00 
▕██████████████████▏ 100.0%
applying 2 grafts for mkfontdir-1.0.7 ...
  guix-command  653B                   436KiB/s 00:00 
▕██████████████████▏ 100.0%
applying 6 grafts for texinfo-6.8 ...
  guix-daemon  402B                    105KiB/s 00:00 
▕██████████████████▏ 100.0%
  guix-08360a2cd  800B                  94KiB/s 00:00 
▕██████████████████▏ 100.0%
building CA certificate bundle...
listing Emacs sub-directories...
building fonts directory...
building directory of Info manuals...
...


Shouldn't 'guix pull' substitutes also work on foreign distros?
If they should, why don't sytem B get them?

Regards,
Nigko