diff --git a/builder/default.nix b/builder/default.nix
index 90ef1d0..7ce54a3 100644
--- a/builder/default.nix
+++ b/builder/default.nix
@@ -172,6 +172,8 @@ let
       dontConfigure = true;
       dontInstall = true;
 
+      CGO_ENABLED = attrs.CGO_ENABLED or go.CGO_ENABLED;
+
       propagatedBuildInputs = [ go ];
 
       GO_NO_VENDOR_CHECKS = "1";
@@ -253,6 +255,7 @@ let
         inherit (go) GOOS GOARCH;
 
         GO_NO_VENDOR_CHECKS = "1";
+        CGO_ENABLED = attrs.CGO_ENABLED or go.CGO_ENABLED;
 
         GO111MODULE = "on";
         GOFLAGS = [ "-mod=vendor" ] ++ lib.optionals (!allowGoReference) [ "-trimpath" ];
diff --git a/generic.nix b/generic.nix
index 92de832..1af764b 100644
--- a/generic.nix
+++ b/generic.nix
@@ -9,13 +9,11 @@
 , makeWrapper
 , installShellFiles
 , fetchFromGitHub
+, buildGoApplication ? (callPackage ./builder { }).buildGoApplication
+, mkGoEnv ? (callPackage ./builder { }).buildGoApplication
 }:
 
-let
-  builder = callPackage ./builder { };
-
-in
-builder.buildGoApplication {
+buildGoApplication {
   pname = "gomod2nix";
   inherit version modules src go;
 
@@ -25,13 +23,15 @@ builder.buildGoApplication {
 
   nativeBuildInputs = [ makeWrapper installShellFiles ];
 
-  passthru = builder;
+  passthru = {
+    inherit buildGoApplication mkGoEnv;
+  };
 
   postInstall = lib.optionalString (stdenv.buildPlatform == stdenv.targetPlatform) ''
-    $out/bin/gomod2nix completion bash > gomod2nix.bash
-    $out/bin/gomod2nix completion fish > gomod2nix.fish
-    $out/bin/gomod2nix completion zsh > _gomod2nix
-    installShellCompletion gomod2nix.{bash,fish} _gomod2nix
+    installShellCompletion --cmd gomod2nix \
+      --bash <($out/bin/gomod2nix completion bash) \
+      --fish <($out/bin/gomod2nix completion fish) \
+      --zsh <($out/bin/gomod2nix completion zsh)
   '' + ''
     wrapProgram $out/bin/gomod2nix --prefix PATH : ${lib.makeBinPath [ go ]}
   '';