Derivations differ between computers?

[Leo Famulari]

I'm seeing something weird, where Guix is creating different derivations
based on the same Git commit, between two machines of the same system
type:

Computer A:
------
$ lscpu | grep Architecture
Architecture:                    x86_64
$ guix describe
Generation 180  Oct 17 2021 23:07:29    (current)
  guix 473ea16
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: 473ea161a15a13e7d5e7e0724693c1931ff8daaa
$ guix time-machine --commit=c70eadeaed9367e45be3797a17d3a34e5f8f67cd -- build 
--no-grafts hello -d
/gnu/store/260bk0ch4np4h2yz5yqhf8hjbsyhwpmr-hello-2.10.drv
------

Computer B:
------
$ lscpu | grep Architecture
Architecture:                    x86_64
$ guix describe
Generation 23   Oct 18 2021 00:23:51    (current)
  guix 473ea16
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: 473ea161a15a13e7d5e7e0724693c1931ff8daaa
$ guix time-machine --commit=c70eadeaed9367e45be3797a17d3a34e5f8f67cd -- build 
--no-grafts hello -d
/gnu/store/vs34g0npra395dsqyplrjrwlm417a1w4-hello-2.10.drv
------

I've attached the two drv files.

vs34g0npra395dsqyplrjrwlm417a1w4-hello-2.10.drv
Description: Text document

260bk0ch4np4h2yz5yqhf8hjbsyhwpmr-hello-2.10.drv
Description: Text document

signature.asc
Description: PGP signature