services: setup restic backups service

secrets/default.nix

@@ -17,6 +17,7 @@ with lib;
     gandiKey = lib.fileContents ./gandi-api-key.secret;
 
     borg-backup = import ./borg-backup { inherit lib; };
+    restic-backup = import ./restic-backup { inherit lib; };
 
     matrixEmailConfig = import ./matrix-email-config.nix;
   };

secrets/restic-backup/default.nix

@@ -0,0 +1,4 @@
+{ lib }:
+{
+  poseidon-repo = lib.fileContents ./poseidon-repo.secret;
+}