diff --git a/config/dev.yml b/config/dev.yml
--- a/config/dev.yml
+++ b/config/dev.yml
@@ -7,5 +7,3 @@
   url: http://moma.internal.softwareheritage.org:5010
 
 debug: yes
-
-server-type: asgi
diff --git a/config/staging.yml b/config/staging.yml
--- a/config/staging.yml
+++ b/config/staging.yml
@@ -7,5 +7,3 @@
   url: http://webapp.internal.staging.swh.network:5010
 
 debug: no
-
-server-type: asgi
diff --git a/swh/graphql/backends/archive.py b/swh/graphql/backends/archive.py
--- a/swh/graphql/backends/archive.py
+++ b/swh/graphql/backends/archive.py
@@ -15,7 +15,6 @@
     OriginVisitStatus,
     Release,
     Revision,
-    Sha1,
     Sha1Git,
 )
 from swh.model.swhids import ObjectType
@@ -143,5 +142,5 @@
     def get_contents(self, checksums: Dict[str, Any]) -> List[Content]:
         return self.storage.content_find(content=checksums)
 
-    def get_content_data(self, content_sha1: Sha1) -> Optional[bytes]:
-        return self.storage.content_get_data(content=content_sha1)
+    # def get_content_data(self, content_sha1: Sha1) -> Optional[bytes]:
+    #     return self.storage.content_get_data(content=content_sha1)
diff --git a/swh/graphql/resolvers/person.py b/swh/graphql/resolvers/person.py
--- a/swh/graphql/resolvers/person.py
+++ b/swh/graphql/resolvers/person.py
@@ -2,9 +2,3 @@
 # 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 .base_node import BaseNode
-
-
-class PersonNode(BaseNode):
-    """ """
diff --git a/swh/graphql/resolvers/scalars.py b/swh/graphql/resolvers/scalars.py
--- a/swh/graphql/resolvers/scalars.py
+++ b/swh/graphql/resolvers/scalars.py
@@ -21,10 +21,10 @@
 
 
 @id_scalar.serializer
-def serialize_id(value):
-    if type(value) is bytes:
-        return value.hex()
-    return value
+def serialize_id(value) -> str:
+    if type(value) is str:
+        value = value.encode()
+    return value.hex()
 
 
 @datetime_scalar.serializer
diff --git a/swh/graphql/server.py b/swh/graphql/server.py
--- a/swh/graphql/server.py
+++ b/swh/graphql/server.py
@@ -64,6 +64,7 @@
     SWH_CONFIG_FILENAME environment variable defines the
     configuration path to load.
     """
+    from ariadne.asgi import GraphQL
     from starlette.middleware.cors import CORSMiddleware
 
     from .app import schema
@@ -75,14 +76,10 @@
         config_path = os.environ.get("SWH_CONFIG_FILENAME")
         graphql_cfg = load_and_check_config(config_path)
 
-    server_type = graphql_cfg.get("server-type")
-    if server_type == "asgi":
-        from ariadne.asgi import GraphQL
-
-        application = CORSMiddleware(
-            GraphQL(schema, debug=graphql_cfg["debug"], error_formatter=format_error),
-            # FIXME, restrict origins after deploying the JS client
-            allow_origins=["*"],
-            allow_methods=("GET", "POST", "OPTIONS"),
-        )
+    application = CORSMiddleware(
+        GraphQL(schema, debug=graphql_cfg["debug"], error_formatter=format_error),
+        # FIXME, restrict origins after deploying the JS client
+        allow_origins=["*"],
+        allow_methods=("GET", "POST", "OPTIONS"),
+    )
     return application
diff --git a/swh/graphql/tests/functional/test_content.py b/swh/graphql/tests/functional/test_content.py
--- a/swh/graphql/tests/functional/test_content.py
+++ b/swh/graphql/tests/functional/test_content.py
@@ -15,6 +15,7 @@
     query getContent($swhid: SWHID!) {
       content(swhid: $swhid) {
         swhid
+        id
         checksum {
           blake2s256
           sha1
@@ -42,6 +43,7 @@
     archive_url = "https://archive.softwareheritage.org/api/1/"
     response = {
         "swhid": str(content.swhid()),
+        "id": content.sha1_git.hex(),
         "checksum": {
             "blake2s256": content.blake2s256.hex(),
             "sha1": content.sha1.hex(),
diff --git a/swh/graphql/tests/unit/resolvers/test_resolver_factory.py b/swh/graphql/tests/unit/resolvers/test_resolver_factory.py
--- a/swh/graphql/tests/unit/resolvers/test_resolver_factory.py
+++ b/swh/graphql/tests/unit/resolvers/test_resolver_factory.py
@@ -15,4 +15,4 @@
 
     def test_get_connection_resolver_invalid_type(self):
         with pytest.raises(AttributeError):
-            resolver_factory.get_connection_resolver("invalid", None, None)
+            resolver_factory.ConnectionObjectFactory().create("invalid", None, None)
diff --git a/swh/graphql/tests/unit/resolvers/test_scalars.py b/swh/graphql/tests/unit/resolvers/test_scalars.py
new file mode 100644
--- /dev/null
+++ b/swh/graphql/tests/unit/resolvers/test_scalars.py
@@ -0,0 +1,54 @@
+# Copyright (C) 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 pytest
+
+from swh.graphql.errors import InvalidInputError
+from swh.graphql.resolvers import scalars
+
+
+def test_serialize_id():
+    assert scalars.serialize_id("test") == "74657374"
+    assert scalars.serialize_id(b"test") == "74657374"
+
+
+def test_serialize_datetime():
+    assert scalars.serialize_datetime("invalid") is None
+    # python datetime
+    date = datetime.datetime(2020, 5, 17)
+    assert scalars.serialize_datetime(date) == date.isoformat()
+    # FIXME, Timestamp with timezone
+
+
+def test_validate_swhid_invalid():
+    with pytest.raises(InvalidInputError):
+        scalars.validate_swhid("invalid")
+
+
+def test_validate_swhid():
+    swhid = scalars.validate_swhid(f"swh:1:rev:{'1' * 40}")
+    assert str(swhid) == "swh:1:rev:1111111111111111111111111111111111111111"
+
+
+@pytest.mark.parametrize("content_hash", ["invalid", "test:invalid"])
+def test_validate_content_hash_invalid_value(content_hash):
+    with pytest.raises(InvalidInputError) as e:
+        scalars.validate_content_hash(content_hash)
+    assert "Invalid content checksum" in str(e.value)
+
+
+def test_validate_content_hash_invalid_hash_algo():
+    with pytest.raises(InvalidInputError) as e:
+        scalars.validate_content_hash(f"invalid:{'1' * 40}")
+    assert "Invalid hash algorithm" in str(e.value)
+
+
+def test_validate_content_hash():
+    assert (
+        "sha1",
+        b"\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11\x11",
+    ) == scalars.validate_content_hash(f"sha1:{'1' * 40}")
diff --git a/swh/graphql/tests/unit/test_server.py b/swh/graphql/tests/unit/test_server.py
new file mode 100644
--- /dev/null
+++ b/swh/graphql/tests/unit/test_server.py
@@ -0,0 +1,67 @@
+# Copyright (C) 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 pytest
+
+from swh.graphql import server
+
+
+def test_get_storage(mocker):
+    server.storage = None
+    server.graphql_cfg = {"storage": {"test": "test"}}
+    mocker.patch("swh.graphql.server.get_swh_storage", return_value="dummy-storage")
+    assert server.get_storage() == "dummy-storage"
+
+
+def test_get_global_storage(mocker):
+    server.storage = "existing-storage"
+    assert server.get_storage() == "existing-storage"
+
+
+def test_get_search(mocker):
+    server.search = None
+    server.graphql_cfg = {"search": {"test": "test"}}
+    mocker.patch("swh.graphql.server.get_swh_search", return_value="dummy-search")
+    assert server.get_search() == "dummy-search"
+
+
+def test_get_global_search(mocker):
+    server.search = "existing-search"
+    assert server.get_search() == "existing-search"
+
+
+def test_load_and_check_config_no_config():
+    with pytest.raises(EnvironmentError):
+        server.load_and_check_config(config_path=None)
+
+
+def test_load_and_check_config_missing_config_file():
+    with pytest.raises(FileNotFoundError):
+        server.load_and_check_config(config_path="invalid")
+
+
+def test_load_and_check_config_missing_storage_config(mocker):
+    mocker.patch("swh.core.config.read", return_value={"test": "test"})
+    with pytest.raises(KeyError):
+        server.load_and_check_config(config_path="/tmp")
+
+
+def test_load_and_check_config(mocker):
+    mocker.patch("swh.core.config.read", return_value={"storage": {"test": "test"}})
+    cfg = server.load_and_check_config(config_path="/tmp")
+    assert cfg == {"storage": {"test": "test"}}
+
+
+def test_make_app_from_configfile_with_config(mocker):
+    server.graphql_cfg = {"storage": {"test": "test"}, "debug": True}
+    mocker.patch("starlette.middleware.cors.CORSMiddleware", return_value="dummy-app")
+    assert server.make_app_from_configfile() == "dummy-app"
+
+
+def test_make_app_from_configfile_missing_config(mocker):
+    server.graphql_cfg = None
+    with pytest.raises(EnvironmentError):
+        # trying to load config from a non existing env var
+        assert server.make_app_from_configfile()