diff --git a/requirements-swh-server.txt b/requirements-swh-server.txt
--- a/requirements-swh-server.txt
+++ b/requirements-swh-server.txt
@@ -1,4 +1,4 @@
-swh.core[http]
+swh.core[http] >= 0.4
 swh.loader.core >= 0.0.71
 swh.scheduler >= 0.0.39
 swh.model >= 0.3.8
diff --git a/requirements-swh.txt b/requirements-swh.txt
--- a/requirements-swh.txt
+++ b/requirements-swh.txt
@@ -1 +1 @@
-swh.core[http] >= 0.3
+swh.core[http] >= 0.4
diff --git a/swh/deposit/client.py b/swh/deposit/client.py
--- a/swh/deposit/client.py
+++ b/swh/deposit/client.py
@@ -17,7 +17,7 @@
 import requests
 import xmltodict
 
-from swh.core.config import config_basepath, read_raw_config
+from swh.core.config import load_from_envvar
 
 logger = logging.getLogger(__name__)
 
@@ -79,11 +79,10 @@
     """
 
     def __init__(self, config=None, _client=requests):
-        if config is None:
-            config_file = os.environ["SWH_CONFIG_FILENAME"]
-            self.config: Dict[str, Any] = read_raw_config(config_basepath(config_file))
-        else:
+        if config:
             self.config = config
+        else:
+            self.config: Dict[str, Any] = load_from_envvar()
 
         self._client = _client
         self.base_url = self.config["url"].strip("/") + "/"
diff --git a/swh/deposit/config.py b/swh/deposit/config.py
--- a/swh/deposit/config.py
+++ b/swh/deposit/config.py
@@ -94,9 +94,7 @@
     """
 
     def __init__(self):
-        config_file = os.environ["SWH_CONFIG_FILENAME"]
-        conf = config.read_raw_config(config.config_basepath(config_file))
-        self.config: Dict[str, Any] = config.merge_configs(DEFAULT_CONFIG, conf)
+        self.config: Dict[str, Any] = config.load_from_envvar(DEFAULT_CONFIG)
         self.scheduler: SchedulerInterface = get_scheduler(**self.config["scheduler"])
         self.tool = {
             "name": "swh-deposit",
diff --git a/swh/deposit/loader/checker.py b/swh/deposit/loader/checker.py
--- a/swh/deposit/loader/checker.py
+++ b/swh/deposit/loader/checker.py
@@ -4,7 +4,6 @@
 # See top-level LICENSE file for more information
 
 import logging
-import os
 from typing import Any, Dict
 
 from swh.core import config
@@ -21,10 +20,7 @@
     """
 
     def __init__(self):
-        config_file = os.environ["SWH_CONFIG_FILENAME"]
-        self.config: Dict[str, Any] = config.read_raw_config(
-            config.config_basepath(config_file)
-        )
+        self.config: Dict[str, Any] = config.load_from_envvar()
         self.client = PrivateApiDepositClient(config=self.config["deposit"])
 
     def check(self, collection: str, deposit_id: str) -> Dict[str, str]: