diff --git a/tests/timeout.builder.sh b/tests/timeout.builder.sh
index 5a7e08861..1ddb44e99 100644
--- a/tests/timeout.builder.sh
+++ b/tests/timeout.builder.sh
@@ -1,2 +1,2 @@
 echo "\`timeout' builder entering an infinite loop"
-while true ; do echo foo; sleep 1; done
+while true ; do echo -n .; done
diff --git a/tests/timeout.sh b/tests/timeout.sh
index 2101d13a7..4a4769a16 100644
--- a/tests/timeout.sh
+++ b/tests/timeout.sh
@@ -2,23 +2,20 @@
 
 source common.sh
 
-drvPath=$(nix-instantiate timeout.nix)
-
-test "$(nix-store -q --binding system "$drvPath")" = "$system"
-
-echo "derivation is $drvPath"
-
 failed=0
-messages="`nix-store -r --timeout 2 $drvPath 2>&1 || failed=1`"
-if test $failed -ne 0; then
-    echo "error: \`nix-store' succeeded; should have timed out" >&2
+messages="`nix-build timeout.nix --timeout 2 2>&1 || failed=1`"
+if [ $failed -ne 0 ]; then
+    echo "error: \`nix-store' succeeded; should have timed out"
     exit 1
 fi
 
-if ! echo "$messages" | grep "timed out"; then
-    echo "error: \`nix-store' may have failed for reasons other than timeout" >&2
-    echo >&2
-    echo "output of \`nix-store' follows:" >&2
+if ! echo "$messages" | grep -q "timed out"; then
+    echo "error: build may have failed for reasons other than timeout; output:"
     echo "$messages" >&2
     exit 1
 fi
+
+if nix-build timeout.nix --option build-max-log-size 100; then
+    echo "build should have failed"
+    exit 1
+fi