feat(common): set system.configurationRevision

2 files changed, 13 insertions, 0 deletions

diff --git a/nixos/profiles/common/default.nix b/nixos/profiles/common/default.nix
index d891879..d94db86 100644
--- a/nixos/profiles/common/default.nix
+++ b/nixos/profiles/common/default.nix
@@ -6,4 +6,10 @@
     ./basics.nix
     "${sources.agenix}/modules/age.nix"
   ];
+
+  system.configurationRevision =
+    let
+      revision = builtins.getEnv "NIXOS_CONFIG_REVISION";
+    in
+    if revision == "" then null else revision;
 }
diff --git a/nixos/rebuild b/nixos/rebuild
index 395f78d..3589dc4 100755
--- a/nixos/rebuild
+++ b/nixos/rebuild
@@ -9,6 +9,13 @@ if [ ! -d "$hostDir" ]; then
   exit 1
 fi
 
+# Make the configuration repository's commit available to the NixOS module.
+export NIXOS_CONFIG_REVISION
+NIXOS_CONFIG_REVISION=$(git -C "$top" rev-parse --verify HEAD)
+if [[ -n $(git -C "$top" status --porcelain) ]]; then
+  NIXOS_CONFIG_REVISION+="-dirty"
+fi
+
 (
   # The result symlink created in the current directory is registered as a root of the Nix
   # garbage collector, so it's important that we call nixos-rebuild from the host directory.