diff --git a/tests/common.sh.in b/tests/common.sh.in
index a8d56707e..04d605e34 100644
--- a/tests/common.sh.in
+++ b/tests/common.sh.in
@@ -26,7 +26,6 @@ mkdir -p $TEST_HOME
 export PATH=@bindir@:$PATH
 coreutils=@coreutils@
 
-export NIX_BUILD_HOOK=
 export dot=@dot@
 export xmllint="@xmllint@"
 export SHELL="@bash@"