How to get all Nix flake check outputs?

CI is having trouble building my NixOS tests, so I’d like to push all the nix flake check outputs to Cachix. However, I’ve already run the resource-hungry and time-consuming tests, and I don’t want to do a full garbage collection and run the tests again with cachix watch-exec. Instead, I’d like to just list the output paths of nix flake check and pass those to cachix push. Is this possible? I don’t want to create some clunky nix build --no-link --print-out-paths .#checks.<arch>.<name> loop.

not sure if there’s something built into nix, but nix-fast-build might help