Must check out code to get nixpkgs.rev

.circleci/config.yml

@@ -46,6 +46,8 @@ jobs:
             # Required for the checkout step
             nix-env -i git openssh
 
+      - "checkout"
+
       - restore_cache:
           # Get all of Nix's state relating to the particular revision of
           # nixpkgs we're using.  It will always be the same.  CircleCI
@@ -67,8 +69,6 @@ jobs:
             - privatestorageio-nix-store-v1-{{ checksum "nixpkgs.rev" }}
             - privatestorageio-nix-store-v1-
 
-      - "checkout"
-
       - save_cache:
           name: "Cache Nix Store Paths"
           key: privatestorageio-nix-store-v1-{{ checksum "nixpkgs.rev" }}