diff --git a/pyproject.toml b/pyproject.toml
index 6828563c9..1aa9c1122 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,7 +62,6 @@ ignore = [
   "F403",
   "F405",
   "F541",
-  "F821",
   "F841",
   "ISC003",  # micropython does not support implicit concatenation of f-strings
   "PIE810",  # micropython does not support passing tuples to .startswith or .endswith
@@ -91,3 +90,10 @@ max-statements = 166
 
 [tool.ruff.per-file-ignores]
 "micropython/aiorepl/aiorepl.py" = ["PGH001"]
+
+# manifest.py files are evaluated with some global names pre-defined
+"**/manifest.py" = ["F821"]
+"ports/**/boards/manifest*.py" = ["F821"]
+
+# ble multitests are evaluated with some names pre-defined
+"micropython/bluetooth/aioble/multitests/*" = ["F821"]