diff --git a/test/sep/localbuild_test.ww b/test/sep/localbuild_test.ww
index dec0861e..fd61bb86 100644
--- a/test/sep/localbuild_test.ww
+++ b/test/sep/localbuild_test.ww
@@ -956,7 +956,7 @@ fn writediamond(td: str, reverse: bool) str = {
 			"/.wwtool.w6a")), testenv.readfile(assembler))
 		    || !testenv.same(testenv.readfile(strings.concat(work,
 			"/.wwtool.stamp")),
-			"ww workdir fmt 17 mode build asm 0\n")) {
+			"ww workdir fmt 18 mode build asm 0\n")) {
 			fail("driver-identity", "persistent artifacts or identities are incomplete");
 		};
 		let coldwwi: str = testenv.readfile(strings.concat(work, "/dep.wwi"));