unexpected reproducibility of reproducible blog post?

[zimoun]

Dear,

Based on the nice blog post [1], instead of really travelling I just
travel in time. :-)
If I read correctly and if I did not do any mistake, the final hash is
not the same now than before. It is not what I was expecting.

Expected output (blog post):
/gnu/store/iqn9yyvi8im18g7y9f064lw9s9knxp0w-docker-pack.tar

Returned output:
/gnu/store/klisfr3a4wxb9dc5sgibb45kky72kg65-docker-pack.tar

Has the file 'guix-version-for-reproduction.txt' been tracked?
Is really the commit 769b96b62e8c09b078f73adc09fb860505920f8f used to
produce the Docker image listed in the blog post?


Thank you in advance.

All the best,
simon


--8<---------------cut here---------------start------------->8---
guix describe
Generation 11   Apr 26 2020 19:24:23    (current)
  guix ca4b558
    repository URL: https://git.savannah.gnu.org/git/guix.git
    branch: master
    commit: ca4b55882a0f6b4ba46253485afb82ec000f8fc2
--8<---------------cut here---------------end--------------->8---

--8<---------------cut here---------------start------------->8---
  guix time-machine --commit=769b96b62e8c09b078f73adc09fb860505920f8f \
       --  pack -f docker -C none \
       -S /bin=bin -S /lib=lib -S /share=share -S /etc=etc \
       gcc-toolchain
--8<---------------cut here---------------end--------------->8---


[1] https://guix.gnu.org/blog/2020/reproducible-computations-with-guix/