diff --git a/.gitignore b/.gitignore
index dbf1c80..80efc9e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,7 @@
-./build/*
+# A leading ./ is not a valid gitignore pattern, so "./build/*" matched nothing
+# and every out-of-tree build tree showed up as untracked. This also covers the
+# instrumented trees scripts/coverage.py and the AKGL_COVERAGE option create.
+build*/
 .aider*
 *~