diff --git a/apricot/apricot_server.py b/apricot/apricot_server.py
index 0cca36c..d7f65c8 100644
--- a/apricot/apricot_server.py
+++ b/apricot/apricot_server.py
@@ -18,6 +18,7 @@ def __init__(
         client_secret: str,
         domain: str,
         port: int,
+        uid_attribute: str,
         **kwargs: Any,
     ) -> None:
         # Log to stdout
@@ -29,6 +30,7 @@ def __init__(
                 client_id=client_id,
                 client_secret=client_secret,
                 domain=domain,
+                uid_attribute=uid_attribute,
                 **kwargs,
             )
         except Exception as exc:
diff --git a/apricot/oauth/microsoft_entra_client.py b/apricot/oauth/microsoft_entra_client.py
index 148163f..3b4ae6a 100644
--- a/apricot/oauth/microsoft_entra_client.py
+++ b/apricot/oauth/microsoft_entra_client.py
@@ -41,7 +41,18 @@ def groups(self) -> list[LDAPAttributeDict]:
     def users(self) -> list[LDAPAttributeDict]:
         output = []
         try:
-            user_data = self.query("https://graph.microsoft.com/v1.0/users/")
+            queries = [
+                "displayName",
+                "givenName",
+                "id",
+                "mail",
+                "surname",
+                "userPrincipalName",
+                self.uid_attribute,
+            ]
+            user_data = self.query(
+                f"https://graph.microsoft.com/v1.0/users?$select={','.join(queries)}"
+            )
             for user_dict in user_data["value"]:
                 attributes = {k: [v if v else ""] for k, v in dict(user_dict).items()}
                 attributes["objectclass"] = [
@@ -62,6 +73,7 @@ def users(self) -> list[LDAPAttributeDict]:
                 attributes["domain"] = [
                     str(user_dict["userPrincipalName"]).split("@")[1]
                 ]
+                attributes["uid"] = [str(user_dict[self.uid_attribute])]
                 output.append(attributes)
         except KeyError:
             pass
diff --git a/apricot/oauth/oauth_client.py b/apricot/oauth/oauth_client.py
index d3dcdb3..eeaefdf 100644
--- a/apricot/oauth/oauth_client.py
+++ b/apricot/oauth/oauth_client.py
@@ -24,11 +24,13 @@ def __init__(
         redirect_uri: str,
         scopes: list[str],
         token_url: str,
+        uid_attribute: str,
     ) -> None:
         # Set attributes
         self.client_secret = client_secret
         self.domain = domain
         self.token_url = token_url
+        self.uid_attribute = uid_attribute
         # Allow token scope to not match requested scope. (Other auth libraries allow
         # this, but Requests-OAuthlib raises exception on scope mismatch by default.)
         os.environ["OAUTHLIB_RELAX_TOKEN_SCOPE"] = "1"  # noqa: S105
diff --git a/docker/entrypoint.sh b/docker/entrypoint.sh
index 6655fdd..00789e9 100644
--- a/docker/entrypoint.sh
+++ b/docker/entrypoint.sh
@@ -2,6 +2,7 @@
 # shellcheck disable=SC2086
 # shellcheck disable=SC2089
 
+# Required arguments
 if [ -z "${BACKEND}" ]; then
     echo "BACKEND environment variable is not set"
     exit 1
@@ -22,6 +23,17 @@ if [ -z "${DOMAIN}" ]; then
     exit 1
 fi
 
+if [ -z "${UID_ATTRIBUTE}" ]; then
+    echo "UID_ATTRIBUTE environment variable is not set"
+    exit 1
+fi
+
+# Arguments with defaults
+if [ -z "${PORT}" ]; then
+    echo "PORT environment variable is not set: using default of 1389"
+    PORT="1389"
+fi
+
 # Optional arguments
 EXTRA_OPTS=""
 if [ -n "${ENTRA_TENANT_ID}" ]; then
@@ -34,5 +46,6 @@ hatch run python run.py \
     --client-id "$CLIENT_ID" \
     --client-secret "$CLIENT_SECRET"  \
     --domain "$DOMAIN" \
-    --port 1389 \
+    --port "${PORT}" \
+    --uid-attribute "${UID_ATTRIBUTE}" \
     $EXTRA_OPTS
diff --git a/run.py b/run.py
index e1eeb6b..75f3c11 100644
--- a/run.py
+++ b/run.py
@@ -16,6 +16,7 @@
         parser.add_argument("-p", "--port", type=int, default=1389, help="Port to run on.")
         parser.add_argument("-i", "--client-id", type=str, help="OAuth client ID.")
         parser.add_argument("-s", "--client-secret", type=str, help="OAuth client secret.")
+        parser.add_argument("-u", "--uid-attribute", type=str, help="Which user attribute to use for UID.")
         # Options for Microsoft Entra backend
         group = parser.add_argument_group("Microsoft Entra")
         group.add_argument("-t", "--entra-tenant-id", type=str, help="Microsoft Entra tenant ID.", required=False)