diff --git a/helpers/setuid/builder.sh b/helpers/setuid/builder.sh
deleted file mode 100644
index 574a73ac11c..00000000000
--- a/helpers/setuid/builder.sh
+++ /dev/null
@@ -1,7 +0,0 @@
-source $stdenv/setup
-
-ensureDir $out/bin
-
-gcc -Wall -O2 -DWRAPPER_DIR=\"$wrapperDir\" $setuidWrapper -o $out/bin/setuid-wrapper
-
-strip -s $out/bin/setuid-wrapper
diff --git a/helpers/setuid/default.nix b/helpers/setuid/default.nix
index 559ecca162f..362bd937cc4 100644
--- a/helpers/setuid/default.nix
+++ b/helpers/setuid/default.nix
@@ -2,7 +2,9 @@
 
 stdenv.mkDerivation {
   name = "setuid-wrapper";
-  builder = ./builder.sh;
-  setuidWrapper = ./setuid-wrapper.c;
-  inherit wrapperDir;
+  buildCommand = ''
+    ensureDir $out/bin
+    gcc -Wall -O2 -DWRAPPER_DIR=\"${wrapperDir}\" ${./setuid-wrapper.c} -o $out/bin/setuid-wrapper
+    strip -s $out/bin/setuid-wrapper
+  '';
 }