1 files changed, 14 insertions, 5 deletions
diff --git a/nixpkgs/nixos/modules/services/backup/zrepl.nix b/nixpkgs/nixos/modules/services/backup/zrepl.nix
index 4356479b6635..ea858a8b77db 100644
--- a/nixpkgs/nixos/modules/services/backup/zrepl.nix
+++ b/nixpkgs/nixos/modules/services/backup/zrepl.nix
@@ -13,11 +13,17 @@ in
     services.zrepl = {
       enable = mkEnableOption "zrepl";
 
+      package = mkOption {
+        type = types.package;
+        default = pkgs.zrepl;
+        defaultText = literalExpression "pkgs.zrepl";
+        description = lib.mdDoc "Which package to use for zrepl";
+      };
+
       settings = mkOption {
         default = { };
-        description = ''
-          Configuration for zrepl. See <link
-          xlink:href="https://zrepl.github.io/configuration.html"/>
+        description = lib.mdDoc ''
+          Configuration for zrepl. See <https://zrepl.github.io/configuration.html>
           for more information.
         '';
         type = types.submodule {
@@ -30,14 +36,17 @@ in
   ### Implementation ###
 
   config = mkIf cfg.enable {
-    environment.systemPackages = [ pkgs.zrepl ];
+    environment.systemPackages = [ cfg.package ];
 
     # zrepl looks for its config in this location by default. This
     # allows the use of e.g. `zrepl signal wakeup <job>` without having
     # to specify the storepath of the config.
     environment.etc."zrepl/zrepl.yml".source = configFile;
 
-    systemd.packages = [ pkgs.zrepl ];
+    systemd.packages = [ cfg.package ];
+
+    # Note that pkgs.zrepl copies and adapts the upstream systemd unit, and
+    # the fields defined here only override certain fields from that unit.
     systemd.services.zrepl = {
       requires = [ "local-fs.target" ];
       wantedBy = [ "zfs.target" ];