We may be OK with the performance penalty that the
nixpkgs.python38incurs due to the lack of optimizations. At least we understand why!
No need to live with that! As @FRidh merged python3: fix overriding of interpreters, closes #163639 · NixOS/nixpkgs@ba02fd0 · GitHub you can again use what is described in the manual: Instead of simply using python38 in your expressions, you “just” have to use python38.override { enableOptimizations = true; reproducibleBuild = false; ... } how it’s described in “15.25.2.2. Optimizations” of the nixpkgs manual: