diff --git a/nix/lib.nix b/nix/lib.nix
index 90554403..1e7dbacb 100644
--- a/nix/lib.nix
+++ b/nix/lib.nix
@@ -77,10 +77,7 @@ let
                       shell;
                 };
               # Pass the wrapped system-manager binary down
-              # TODO: Use nixpkgs version by default.
-              system-manager = pkgs.callPackage ./packages/wrapper.nix {
-                system-manager-unwrapped = pkgs.callPackage ../package.nix { };
-              };
+              system-manager = config.system-manager.package;
               userborn = userborn.packages.${config.nixpkgs.hostPlatform}.default;
             };
           };
@@ -118,10 +115,8 @@ let
         inherit (eval) config options;
         inherit (config.nixpkgs) pkgs;
 
-        # Build system-manager package for use in toplevel
-        system-manager = pkgs.callPackage ./packages/wrapper.nix {
-          system-manager-unwrapped = pkgs.callPackage ../package.nix { };
-        };
+        # Retrieve system-manager package for use in toplevel
+        system-manager = config.system-manager.package;
 
         returnIfNoAssertions =
           drv:
diff --git a/nix/modules/default.nix b/nix/modules/default.nix
index 76147858..97dfe75e 100644
--- a/nix/modules/default.nix
+++ b/nix/modules/default.nix
@@ -129,6 +129,21 @@
       };
 
       system-manager = {
+        package = lib.mkOption {
+          type = lib.types.package;
+          # TODO: Use nixpkgs version by default.
+          default = pkgs.callPackage ../packages/wrapper.nix {
+            system-manager-unwrapped = pkgs.callPackage ../../package.nix { };
+          };
+          example = "pkgs.system-manager";
+          defaultText = lib.literalExpression ''
+            pkgs.callPackage ''${system-manager}/nix/modules/packages/wrapper.nix {
+              system-manager-unwrapped = pkgs.callPackage ''${system-manager}/package.nix { };
+            }
+          '';
+          description = "System-manager binary to use.";
+        };
+
         allowAnyDistro = lib.mkEnableOption "the usage of system-manager on untested distributions";
 
         linkCurrentSystem = lib.mkOption {