diff --git a/tests/test_core.py b/tests/test_core.py
new file mode 100644
index 0000000..b50b07c
--- /dev/null
+++ b/tests/test_core.py
@@ -0,0 +1,5 @@
+from cashu.core.split import amount_split
+
+
+def test_get_output_split():
+    assert amount_split(13) == [1, 4, 8]
diff --git a/tests/test_mint.py b/tests/test_mint.py
index ad5713b..a949b0f 100644
--- a/tests/test_mint.py
+++ b/tests/test_mint.py
@@ -112,8 +112,3 @@ async def test_generate_promises(ledger: Ledger):
         promises[0].C_
         == "032dfadd74bb3abba8170ecbae5401507e384eafd312defda94148fa37314c0ef0"
     )
-
-
-@pytest.mark.asyncio
-async def test_get_output_split(ledger: Ledger):
-    assert ledger._get_output_split(13) == [1, 4, 8]