diff --git a/protostar/compiler/compiled_contract_writer.py b/protostar/compiler/compiled_contract_writer.py
index 24207b2821..712df88709 100644
--- a/protostar/compiler/compiled_contract_writer.py
+++ b/protostar/compiler/compiled_contract_writer.py
@@ -17,13 +17,17 @@ def save(self, output_dir: Path) -> None:
     def save_compiled_contract(self, output_dir: Path) -> None:
         self._create_output_dir(output_dir)
         serialized_contract = self._contract.Schema().dump(self._contract)
-        self._save_as_json(data=serialized_contract, path=output_dir)
+        self._save_as_json(
+            data=serialized_contract, path=output_dir / f"{self._contract_name}.json"
+        )
 
     def save_compiled_contract_abi(self, output_dir: Path) -> None:
         if not self._contract.abi:
             return
         self._create_output_dir(output_dir)
-        self._save_as_json(data=self._contract.abi, path=output_dir)
+        self._save_as_json(
+            data=self._contract.abi, path=output_dir / f"{self._contract_name}_abi.json"
+        )
 
     @staticmethod
     def _create_output_dir(output_dir: Path):
@@ -31,6 +35,7 @@ def _create_output_dir(output_dir: Path):
 
     @staticmethod
     def _save_as_json(data: Any, path: Path):
+        assert path.suffix == ".json"
         with open(
             path,
             mode="w",