diff --git a/requirements-azure.txt b/requirements-azure.txt
new file mode 100644
--- /dev/null
+++ b/requirements-azure.txt
@@ -0,0 +1 @@
+azure-storage-blob >= 12.0, != 12.9.0  # version 12.9.0 breaks mypy https://github.com/Azure/azure-sdk-for-python/pull/20891
diff --git a/requirements-libcloud.txt b/requirements-libcloud.txt
new file mode 100644
--- /dev/null
+++ b/requirements-libcloud.txt
@@ -0,0 +1 @@
+apache-libcloud
diff --git a/requirements-test.txt b/requirements-test.txt
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,5 +1,3 @@
-apache-libcloud
-azure-storage-blob >= 12.0, != 12.9.0  # version 12.9.0 breaks mypy https://github.com/Azure/azure-sdk-for-python/pull/20891
 pytest < 7.0.0  # v7.0.0 removed _pytest.tmpdir.TempdirFactory, which is used by some of the pytest plugins we use
 pytest-asyncio
 pytest-mock
diff --git a/requirements-winery.txt b/requirements-winery.txt
new file mode 100644
--- /dev/null
+++ b/requirements-winery.txt
@@ -0,0 +1,2 @@
+psycopg2
+sh
diff --git a/requirements.txt b/requirements.txt
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,13 +2,8 @@
 # should match https://pypi.python.org/pypi names. For the full spec or
 # dependency lines, see https://pip.readthedocs.org/en/1.1/requirements.html
 
-# remote storage API server
 click
-requests
-psycopg2
-sh
 typing-extensions
 
-# optional dependencies
-# apache-libcloud
-# azure-storage-blob >= 12.0
+# seaweedfs backend
+requests
diff --git a/setup.py b/setup.py
--- a/setup.py
+++ b/setup.py
@@ -48,7 +48,15 @@
     install_requires=parse_requirements() + parse_requirements("swh"),
     setup_requires=["setuptools-scm"],
     use_scm_version=True,
-    extras_require={"testing": parse_requirements("test")},
+    extras_require={
+        "testing": parse_requirements("test")
+        + parse_requirements("azure")
+        + parse_requirements("libcloud")
+        + parse_requirements("winery"),
+        "azure": parse_requirements("azure"),
+        "libcloud": parse_requirements("libcloud"),
+        "winery": parse_requirements("winery"),
+    },
     include_package_data=True,
     entry_points="""
         [swh.cli.subcommands]