diff --git a/contrib/pyln-proto/pyln/proto/message/fundamental_types.py b/contrib/pyln-proto/pyln/proto/message/fundamental_types.py
index 972f18664..4559b9bd3 100644
--- a/contrib/pyln-proto/pyln/proto/message/fundamental_types.py
+++ b/contrib/pyln-proto/pyln/proto/message/fundamental_types.py
@@ -235,6 +235,8 @@ def fundamental_types():
             BigSizeType('bigsize'),
             # FIXME: See https://github.com/lightningnetwork/lightning-rfc/pull/778
             BigSizeType('varint'),
+            # FIXME
+            IntegerType('u8', 1, 'B'),
             ]
 
 
diff --git a/contrib/pyln-proto/tests/test_fundamental_types.py b/contrib/pyln-proto/tests/test_fundamental_types.py
index 5dd5ac345..5513a13e5 100644
--- a/contrib/pyln-proto/tests/test_fundamental_types.py
+++ b/contrib/pyln-proto/tests/test_fundamental_types.py
@@ -74,4 +74,4 @@ def test_fundamental_types():
             t.write(buf, v, None)
             assert buf.getvalue() == test[1]
 
-    assert untested == set(['varint'])
+    assert untested == set(['varint', 'u8'])