diff --git a/tests/opt/README.md b/tests/opt/README.md
new file mode 100644
index 000000000..f6d55e1fa
--- /dev/null
+++ b/tests/opt/README.md
@@ -0,0 +1,5 @@
+# Simple tests
+
+## Disabled
+
+- `opt_lut`: we do not support `abc9`
diff --git a/tests/opt/opt_lut.ys b/tests/opt/opt_lut.ys.skip
similarity index 100%
rename from tests/opt/opt_lut.ys
rename to tests/opt/opt_lut.ys.skip