diff --git a/doc/build-helpers/testers.chapter.md b/doc/build-helpers/testers.chapter.md
index 80d293cf1c70..34cfc00a4953 100644
--- a/doc/build-helpers/testers.chapter.md
+++ b/doc/build-helpers/testers.chapter.md
@@ -205,7 +205,7 @@ runCommand "example" {
 
 :::
 
-## `testEqualContents` {#tester-equalContents}
+## `testEqualContents` {#tester-testEqualContents}
 
 Check that two paths have the same contents.