Hi, Commit a53b000 updates the Git submodule for ‘nix-upstream’ to Nix 1.3. So make sure to run ‘git submodule update’ followed by ./nix/sync-with-upstream to actually use that code.
When you run it on your existing store, the first time you run guix-build or some other tool, you’ll see this message: removing immutable bits from the Nix store (this may take a while)... It will indeed take a bit of time (a few minutes on an SSD with a large store.) More details at: http://thread.gmane.org/gmane.linux.distributions.nixos/10055 (Nix 1.3 is just a bug-fix release, see <http://hydra.nixos.org/build/3668901/download/3/release-notes/>.) Ludo’.
