diff --git a/.pylintrc b/.pylintrc
index 2176ad9..49da7d1 100644
--- a/.pylintrc
+++ b/.pylintrc
@@ -33,7 +33,8 @@ disable=
     too-few-public-methods,
     cyclic-import,
     import-error,
-    no-name-in-module
+    no-name-in-module,
+    redefined-outer-name,
 
 
 [REPORTS]
diff --git a/src/crllm/cli.py b/src/crllm/cli.py
index b2e3762..57f059d 100644
--- a/src/crllm/cli.py
+++ b/src/crllm/cli.py
@@ -13,15 +13,29 @@ def cli():
         description="Get Code Reviews from large language models."
     )
 
-    parser.add_argument("input_file", help="Path to the source code file")
+    parser.add_argument("input", help="Path to the sources")
     parser.add_argument(
-        "-c", help="Path to the config file", default="crllm_config.toml"
+        "-c", "--config", help="Path to the config file", default="crllm_config.toml"
+    )
+    parser.add_argument(
+        "-l",
+        "--loader",
+        help="Loader to use",
+        required=False,
+        choices=["file", "git", "git_compare"],
     )
 
     args = parser.parse_args()
-    config_service.get_config(args.c)
 
-    app(args.input_file)
+    config = {"crllm": {}}
+
+    if args.loader:
+        config["crllm"]["loader"] = args.loader
+
+    config_service.set_config_path(args.config)
+    config_service.override_config(config)
+
+    app(args.input)
 
 
 if __name__ == "__main__":
diff --git a/src/crllm/config/config_service.py b/src/crllm/config/config_service.py
index cf9beed..610df7b 100644
--- a/src/crllm/config/config_service.py
+++ b/src/crllm/config/config_service.py
@@ -7,24 +7,34 @@
 
 
 class ConfigService:
-    configPath = os.path.join(CONFIG_DIR, "config.toml")
+    default_config_path = os.path.join(CONFIG_DIR, "config.toml")
+    config_path = "./crllm_config.toml"
     config = None
 
-    def get_config(self, path="./crllm_config.toml"):
+    def set_config_path(self, path):
+        self.config_path = path
+
+    def get_config(self):
         if self.config:
             return self.config
 
-        self.config = toml.load(self.configPath)
+        self.config = toml.load(self.default_config_path)
 
-        if not os.path.isfile(path):
+        if not os.path.isfile(self.config_path):
             return self.config
 
-        project_config = toml.load(path)
-        self.config = always_merger.merge(self.config, project_config)
+        project_config = toml.load(self.config_path)
+        self.override_config(project_config)
 
         logging.debug(self.config)
 
         return self.config
 
+    def override_config(self, config: dict):
+        if not self.config:
+            self.get_config()
+
+        self.config = always_merger.merge(self.config, config)
+
 
 config_service = ConfigService()
diff --git a/src/crllm/test/unit/config/config_service_test.py b/src/crllm/test/unit/config/config_service_test.py
new file mode 100644
index 0000000..12d5257
--- /dev/null
+++ b/src/crllm/test/unit/config/config_service_test.py
@@ -0,0 +1,36 @@
+import pytest
+from crllm.config.config_service import ConfigService
+
+
+@pytest.fixture()
+def mock_config_file(tmpdir):
+    tmpdir.join("config.toml").write(
+        """
+    [crllm]
+        loader = "foo"
+        provider = "bar"
+    """
+    )
+
+    return str(tmpdir.join("config.toml"))
+
+
+def test_get_config(mock_config_file):
+    config_service = ConfigService()
+    config_service.set_config_path(mock_config_file)
+
+    result = config_service.get_config()
+
+    assert result["crllm"]["loader"] == "foo"
+    assert result["crllm"]["provider"] == "bar"
+
+
+def test_override(mock_config_file):
+    config_service = ConfigService()
+    config_service.set_config_path(mock_config_file)
+
+    config_service.override_config({"crllm": {"loader": "test"}})
+
+    result = config_service.get_config()
+
+    assert result["crllm"]["loader"] == "test"