diff --git a/pkgs/development/go-modules/generic/default.nix b/pkgs/development/go-modules/generic/default.nix
index 7ab3c892f569..b5ddba9b981c 100644
--- a/pkgs/development/go-modules/generic/default.nix
+++ b/pkgs/development/go-modules/generic/default.nix
@@ -80,8 +80,8 @@ go.stdenv.mkDerivation (
     PIDS=()
     if [ -n "$subPackages" ] ; then
         for p in $subPackages ; do
-            go install $buildFlags "''${buildFlagsArray[@]}" -p $NIX_BUILD_CORES -v $goPackagePath/$p
-            #PIDS+=("$!")
+            go install $buildFlags "''${buildFlagsArray[@]}" -p $NIX_BUILD_CORES -v $goPackagePath/$p &
+            PIDS+=("$!")
         done
     else
         pushd go/src
@@ -99,8 +99,8 @@ go.stdenv.mkDerivation (
             if [ -n "$OUT" ]; then
               echo "$OUT" >&2
             fi
-          }
-          #PIDS+=("$!")
+          } &
+          PIDS+=("$!")
         done < <(find $goPackagePath -type f -name \*.go -exec dirname {} \; | sort | uniq)
         popd
     fi
@@ -119,16 +119,16 @@ go.stdenv.mkDerivation (
     PIDS=()
     if [ -n "$subPackages" ] ; then
         for p in $subPackages ; do
-            go test -p $NIX_BUILD_CORES -v $goPackagePath/$p
+            go test -p $NIX_BUILD_CORES -v $goPackagePath/$p &
         done
-        #PIDS+=("$!")
+        PIDS+=("$!")
     else
         pushd go/src
         while read d; do
-            go test -p $NIX_BUILD_CORES -v $d
+            go test -p $NIX_BUILD_CORES -v $d &
         done < <(find $goPackagePath -type f -name \*_test.go -exec dirname {} \; | sort | uniq)
         popd
-        #PIDS+=("$!")
+        PIDS+=("$!")
     fi
 
     # Exit on error from the parallel process