diff --git a/pkgs/development/libraries/qt-5/qtbase-setup-hook.sh b/pkgs/development/libraries/qt-5/qtbase-setup-hook.sh
index e7752af4397..4b0bad58335 100644
--- a/pkgs/development/libraries/qt-5/qtbase-setup-hook.sh
+++ b/pkgs/development/libraries/qt-5/qtbase-setup-hook.sh
@@ -116,7 +116,11 @@ fi
 
 if [ -z "$NIX_QT5_TMP" ]; then
     if [ -z "$NIX_QT_SUBMODULE" ]; then
-        NIX_QT5_TMP=$(pwd)/__nix_qt5__
+        if [ -z "$IN_NIX_SHELL" ]; then
+            NIX_QT5_TMP=$(pwd)/__nix_qt5__
+        else
+            NIX_QT5_TMP=$(mktemp -d)
+        fi
     else
         NIX_QT5_TMP=$out
     fi