diff --git a/api/.devcontainer/devcontainer.json b/api/.devcontainer/devcontainer.json
index 2ee4cb2..d8d6a33 100644
--- a/api/.devcontainer/devcontainer.json
+++ b/api/.devcontainer/devcontainer.json
@@ -4,7 +4,7 @@
 	"name": "Advent22 API",
 	"dockerComposeFile": "docker-compose.yml",
 	"service": "api",
-	"workspaceFolder": "/workspaces/${localWorkspaceFolderBasename}",
+	"workspaceFolder": "/workspaces/advent22/${localWorkspaceFolderBasename}",
 	// Configure tool-specific properties.
 	"customizations": {
 		// Configure properties specific to VS Code.
diff --git a/api/.devcontainer/docker-compose.yml b/api/.devcontainer/docker-compose.yml
index ea9650f..ae045b7 100644
--- a/api/.devcontainer/docker-compose.yml
+++ b/api/.devcontainer/docker-compose.yml
@@ -16,7 +16,7 @@ services:
       TZ: "Europe/Berlin"
 
     volumes:
-      - "../..:/workspaces:cached"
+      - "../..:/workspaces/advent22:cached"
     
     # Overrides default command so things don't shut down after the process ends.
     command: "sleep infinity"
diff --git a/api/.env b/api/.env
new file mode 100644
index 0000000..f1ecb50
--- /dev/null
+++ b/api/.env
@@ -0,0 +1 @@
+COMPOSE_PROJECT_NAME="advent22_api"
diff --git a/api/.gitignore b/api/.gitignore
index 55be276..d4c7259 100644
--- a/api/.gitignore
+++ b/api/.gitignore
@@ -152,3 +152,4 @@ cython_debug/
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 #.idea/
 
+api.conf
diff --git a/api/advent22_api/core/dav/helpers.py b/api/advent22_api/core/dav/helpers.py
index e15617d..a6e2bd2 100644
--- a/api/advent22_api/core/dav/helpers.py
+++ b/api/advent22_api/core/dav/helpers.py
@@ -1,4 +1,5 @@
 from json import JSONDecodeError
+from typing import Callable, Hashable
 
 import requests
 from cachetools.keys import hashkey
@@ -8,11 +9,17 @@ from redis.typing import EncodableT
 from webdav3.client import Client as __WebDAVclient
 
 
-def davkey(name, _, *args, **kwargs):
-    """Return a cache key for use with cached methods."""
+def davkey(
+    name: str,
+    slice: slice = slice(1, None),
+) -> Callable[..., tuple[Hashable, ...]]:
+    def func(*args, **kwargs) -> tuple[Hashable, ...]:
+        """Return a cache key for use with cached methods."""
 
-    key = hashkey(name, *args, **kwargs)
-    return hashkey(*(str(key_item) for key_item in key))
+        key = hashkey(name, *args[slice], **kwargs)
+        return hashkey(*(str(key_item) for key_item in key))
+
+    return func
 
 
 class WebDAVclient(__WebDAVclient):
diff --git a/api/advent22_api/core/dav/webdav.py b/api/advent22_api/core/dav/webdav.py
index 4c316a5..acb5097 100644
--- a/api/advent22_api/core/dav/webdav.py
+++ b/api/advent22_api/core/dav/webdav.py
@@ -1,4 +1,3 @@
-import functools
 import logging
 import re
 from io import BytesIO
@@ -34,10 +33,7 @@ class WebDAV:
 
     @classmethod
     @asyncify
-    @cachedmethod(
-        cache=lambda cls: cls._cache,
-        key=functools.partial(davkey, "list_files"),
-    )
+    @cachedmethod(cache=lambda cls: cls._cache, key=davkey("list_files"))
     def list_files(
         cls,
         directory: str = "",
@@ -55,10 +51,7 @@ class WebDAV:
 
     @classmethod
     @asyncify
-    @cachedmethod(
-        cache=lambda cls: cls._cache,
-        key=functools.partial(davkey, "exists"),
-    )
+    @cachedmethod(cache=lambda cls: cls._cache, key=davkey("exists"))
     def exists(cls, path: str) -> bool:
         """
         `True` iff there is a WebDAV resource at `path`
@@ -69,10 +62,7 @@ class WebDAV:
 
     @classmethod
     @asyncify
-    @cachedmethod(
-        cache=lambda cls: cls._cache,
-        key=functools.partial(davkey, "read_bytes"),
-    )
+    @cachedmethod(cache=lambda cls: cls._cache, key=davkey("read_bytes"))
     def read_bytes(cls, path: str) -> bytes:
         """
         Load WebDAV file from `path` as bytes
@@ -105,7 +95,7 @@ class WebDAV:
         cls._webdav_client.upload_to(buffer, path)
 
         # invalidate cache entry
-        cls._cache.pop(davkey("read_bytes", None, path))
+        cls._cache.pop(davkey("read_bytes")(path))
 
     @classmethod
     async def write_str(cls, path: str, content: str, encoding="utf-8") -> None:
diff --git a/api/advent22_api/core/settings.py b/api/advent22_api/core/settings.py
index c509978..8ddcfee 100644
--- a/api/advent22_api/core/settings.py
+++ b/api/advent22_api/core/settings.py
@@ -48,7 +48,7 @@ class Settings(BaseSettings):
     """
 
     model_config = SettingsConfigDict(
-        env_file=".env",
+        env_file="api.conf",
         env_file_encoding="utf-8",
         env_nested_delimiter="__",
     )