diff --git a/nimterop.nimble b/nimterop.nimble
index a6fba1e..e2f82b1 100644
--- a/nimterop.nimble
+++ b/nimterop.nimble
@@ -37,8 +37,9 @@ task docs, "Generate docs":
 task test, "Test":
   buildToastTask()
 
-  execTest "tests/tast2.nim"
-  execTest "tests/tast2.nim", "-d:HEADER"
+  when (NimMajor, NimMinor, NimPatch) >= (1, 0, 0):
+    execTest "tests/tast2.nim"
+    execTest "tests/tast2.nim", "-d:HEADER"
 
   execTest "tests/tnimterop_c.nim"
   execTest "tests/tnimterop_c.nim", "-d:FLAGS=\"-f:ast2\""