@Pol @bagder @gonzo_askold @orpach.neocities.org indeed, "replayable" and "hermetic" are better terms for what Nix provides. Some of the bitwise reproducibility of nixpkgs comes from rigorously defining all build inputs, various patches we apply and default build settings we default to. But the brunt of the work is the massive and steller upstream work of https://reproducible-builds.org/, without which nixpkgs would not even be close to bitwise reproducible