diff --git a/lib/default.nix b/lib/default.nix
index 77176052..f66f1f70 100644
--- a/lib/default.nix
+++ b/lib/default.nix
@@ -1,20 +1,15 @@
 { lib, ... }:
 let
   data = import ./data;
+  strings = import ./strings.nix { inherit lib; };
 in
 {
   flake = {
     lib = {
       caddy = import ./caddy.nix { inherit data lib; };
       inherit data;
-
-      toPascalCase =
-        string:
-        let
-          head = lib.toUpper (builtins.substring 0 1 string);
-          tail = builtins.substring 1 (-1) string;
-        in
-        head + tail;
+      inherit strings;
+      inherit (strings) toPascalCase toUpperSnakeCase;
     };
   };
 }
diff --git a/lib/strings.nix b/lib/strings.nix
new file mode 100644
index 00000000..6a2de48c
--- /dev/null
+++ b/lib/strings.nix
@@ -0,0 +1,33 @@
+{ lib, ... }:
+{
+  toPascalCase =
+    string:
+    let
+      head = lib.toUpper (builtins.substring 0 1 string);
+      tail = builtins.substring 1 (-1) string;
+    in
+    head + tail;
+
+  # Taken from nixpkgs Vaultwarden module, licensed MIT
+  # https://github.com/NixOS/nixpkgs/blob/6c9a78c09ff4d6c21d0319114873508a6ec01655/nixos/modules/services/security/vaultwarden/default.nix#L20
+  toUpperSnakeCase =
+    name:
+    let
+      parts = builtins.split "([A-Z0-9]+)" name;
+    in
+    lib.foldl' (
+      key: x:
+      let
+        last = lib.stringLength key - 1;
+      in
+      if lib.isList x then
+        key + lib.optionalString (key != "" && lib.substring last 1 key != "_") "_" + lib.head x
+      else if key != "" && lib.elem (lib.substring 0 1 x) lib.lowerChars then # to handle e.g. [ "disable" [ "2FAR" ] "emember" ]
+        lib.substring 0 last key
+        + lib.optionalString (lib.substring (last - 1) 1 key != "_") "_"
+        + lib.substring last 1 key
+        + lib.toUpper x
+      else
+        key + lib.toUpper x
+    ) "" parts;
+}