diff --git a/swh/loader/package/pypi.py b/swh/loader/package/pypi.py
new file mode 100644
index 0000000..411d15c
--- /dev/null
+++ b/swh/loader/package/pypi.py
@@ -0,0 +1,163 @@
+# Copyright (C) 2019  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
+
+from swh.loader.package.loader import PackageLoader
+from urllib.parse import urljoin, urlparse
+
+
+class PyPIClient:
+    """PyPI client in charge of discussing with the pypi server.
+
+    Args:
+        url (str): PyPI instance's url (e.g: https://pypi.org/project/request)
+        api:
+        - https://pypi.org/pypi/requests/json
+        - https://pypi.org/pypi/requests/1.0.0/json (release description)
+
+    """
+    def __init__(self, url):
+        self.version = __version__
+        _url = urlparse(url)
+        project_name = _url.path.split('/')[-1]
+        self.url = '%s://%s/pypi/%s' % (_url.scheme, _url.netloc, project_name)
+        self.session = requests.session()
+        self.params = {
+            'headers': {
+                'User-Agent': 'Software Heritage PyPI Loader (%s)' % (
+                    __version__
+                )
+            }
+        }
+
+    def _get(self, url):
+        """Get query to the url.
+
+        Args:
+            url (str): Url
+
+        Raises:
+            ValueError in case of failing to query
+
+        Returns:
+            Response as dict if ok
+
+        """
+        response = self.session.get(url, **self.params)
+        if response.status_code != 200:
+            raise ValueError("Fail to query '%s'. Reason: %s" % (
+                url, response.status_code))
+
+        return response.json()
+
+    def info_project(self):
+        """Given a url, retrieve the raw json response
+
+        Returns:
+            Main project information as dict.
+
+        """
+        return self._get(urljoin(self.url, 'json'))
+
+    def info_release(self, release):
+        """Given a project and a release name, retrieve the raw information
+           for said project's release.
+
+        Args:
+            release (dict): Release information
+
+        Returns:
+            Release information as dict
+
+        """
+        return self._get(urljoin(self.url, release, 'json'))
+
+
+class SDist():
+    """In charge of fetching release artifacts, uncompressing it in temporary
+       location, and parsing PKGINFO files.
+
+    """
+
+    def __init__(self, url):
+        """
+
+        Args:
+            url (str): artifact "release" URI (either local or remote)
+
+        """
+        pass
+
+
+class PyPILoader(PackageLoader):
+      """Load pypi origin's artifact releases into swh archive.
+
+    """
+    visit_type = 'pypi'
+
+    def __init__(self, url):
+        super().__init__(url=url, visit_type='pypi')
+        self.client = PyPIClient(url)
+        self.sdist = SDist()
+
+    def get_versions(self):
+        """Return the list of all published package versions.
+
+        """
+        return []
+
+    def retrieve_artifacts(self, version):
+        """Given a release version of a package, retrieve the associated
+           artifact for such version.
+
+        Args:
+            version (str): Package version
+
+        Returns:
+            xxx
+
+        """
+        pass
+
+    def uncompress_artifact_archive(self, artifact_archive_path):
+        """Uncompress artifact archive to a temporary folder and returns its
+           path.
+
+        Args:
+            artifact_archive_path (str): Path to artifact archive to uncompress
+
+        Returns:
+            the uncompressed artifact path (str)
+
+        """
+        pass
+
+    def get_project_metadata(self, artifact):
+        """Given an artifact dict, extract the relevant project metadata.
+           Those will be set within the revision's metadata built
+
+        Args:
+            artifact (dict): A dict of metadata about a release artifact.
+
+        Returns:
+            dict of relevant project metadata (e.g, in pypi loader:
+            {'project_info': {...}})
+
+        """
+        return {}
+
+    def get_revision_metadata(self, artifact):
+        """Given an artifact dict, extract the relevant revision metadata.
+           Those will be set within the 'name' (bytes) and 'message' (bytes)
+           built revision fields.
+
+        Args:
+            artifact (dict): A dict of metadata about a release artifact.
+
+        Returns:
+            dict of relevant revision metadata (name, message keys with values
+            as bytes)
+
+        """
+        pass
diff --git a/swh/loader/package/tests/test_pypi.py b/swh/loader/package/tests/test_pypi.py
new file mode 100644
index 0000000..22d82a9
--- /dev/null
+++ b/swh/loader/package/tests/test_pypi.py
@@ -0,0 +1,40 @@
+# Copyright (C) 2019 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
+
+# scenario
+
+#### configuration error
+
+# badly configured loader fails
+
+#### "edge" cases (for the same origin)
+
+# no release artifact:
+# {visit full, status: uneventful, no contents, etc...}
+
+# problem during loading:
+# {visit: partial, status: uneventful, no snapshot}
+
+# problem during loading: failure early enough in between swh contents...
+# some contents (contents, directories, etc...) have been written in storage
+# {visit: partial, status: eventful, no snapshot}
+
+# problem during loading: failure late enough we can have snapshots (some
+# revisions are written in storage already)
+# {visit: partial, status: eventful, snapshot}
+
+#### "normal" cases (for the same origin)
+
+# release artifact, no prior visit
+# {visit full, status eventful, snapshot}
+
+# release artifact, no new artifact
+# {visit full, status uneventful, same snapshot as before}
+
+# release artifact, new artifact
+# {visit full, status full, new snapshot with shared history as prior snapshot}
+
+# release artifact, old artifact with different checksums
+# {visit full, status full, new snapshot with shared history and some new different history}