diff --git a/swh/loader/cli.py b/swh/loader/cli.py
--- a/swh/loader/cli.py
+++ b/swh/loader/cli.py
@@ -1,4 +1,4 @@
-# Copyright (C) 2019-2021 The Software Heritage developers
+# Copyright (C) 2019-2022 The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
@@ -77,7 +77,7 @@
 
     ctx.obj["config"] = read(config_file)
     logger.debug("config_file: %s", config_file)
-    logger.debug("config: ", ctx.obj["config"])
+    logger.debug("config: %s", ctx.obj["config"])
 
 
 @loader.command(name="run", context_settings=CONTEXT_SETTINGS)
@@ -93,7 +93,10 @@
 
     conf = ctx.obj.get("config", {})
     if "storage" not in conf:
-        raise ValueError("Missing storage configuration key")
+        logger.warning(
+            "No storage configuration detected, using an in-memory storage instead."
+        )
+        conf["storage"] = {"cls": "memory"}
 
     (_, kw) = parse_options(options)
     logger.debug(f"kw: {kw}")
diff --git a/swh/loader/tests/test_cli.py b/swh/loader/tests/test_cli.py
--- a/swh/loader/tests/test_cli.py
+++ b/swh/loader/tests/test_cli.py
@@ -1,15 +1,13 @@
-# Copyright (C) 2019-2021 The Software Heritage developers
+# Copyright (C) 2019-2022 The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import datetime
-import os
 
 from click.formatting import HelpFormatter
 from click.testing import CliRunner
 import pytest
-import yaml
 
 from swh.loader.cli import SUPPORTED_LOADERS, get_loader
 from swh.loader.cli import loader as loader_cli
@@ -66,28 +64,6 @@
     assert result.output.startswith((usage_prefix, usage_prefix2))
 
 
-def test_run_with_configuration_failure(tmp_path):
-    """Triggering a load should fail since configuration is incomplete"""
-    runner = CliRunner()
-
-    conf_path = os.path.join(str(tmp_path), "cli.yml")
-    with open(conf_path, "w") as f:
-        f.write(yaml.dump({}))
-
-    with pytest.raises(ValueError, match="Missing storage"):
-        runner.invoke(
-            loader_cli,
-            [
-                "-C",
-                conf_path,
-                "run",
-                "pypi",
-                "url=https://some-url",
-            ],
-            catch_exceptions=False,
-        )
-
-
 def test_run_pypi(mocker, swh_config):
     """Triggering a load should be ok"""
     mock_loader = mocker.patch("swh.loader.package.pypi.loader.PyPILoader.load")