1. [freedan42x@nixos:~]$ nix-env -e Agda ; nix-env --delete-generations 9 ; nix-store --delete /nix/store/nl7rc8mnavz6j6a955c28p5krx4hj758-Agda-2.5.4.1
  2. uninstalling 'Agda-2.5.4.1'
  3. building '/nix/store/9b6r1rd06pr2fxv1igp33y98apdw96wv-user-environment.drv'...
  4. created 35 symlinks in user environment
  5. removing generation 9
  6. finding garbage collector roots...
  7. removing stale temporary roots file '/nix/var/nix/temproots/22238'
  8. removing stale temporary roots file '/nix/var/nix/temproots/22177'
  9. removing stale temporary roots file '/nix/var/nix/temproots/22442'
  10. removing stale temporary roots file '/nix/var/nix/temproots/22201'
  11. removing stale temporary roots file '/nix/var/nix/temproots/22207'
  12. removing stale temporary roots file '/nix/var/nix/temproots/22193'
  13. 0 store paths deleted, 0.00 MiB freed
  14. error: cannot delete path '/nix/store/nl7rc8mnavz6j6a955c28p5krx4hj758-Agda-2.5.4.1' since it is still alive