diff --git a/Sources/App/Config.swift b/Sources/App/Config.swift
index 03e9284..214d40e 100644
--- a/Sources/App/Config.swift
+++ b/Sources/App/Config.swift
@@ -20,6 +20,11 @@ struct Config: Codable {
     /// Authentication tokens for remotes allowed to write
     let writers: [String]
     
+    /**
+     The folder where the data should be stored.
+     
+     If the folder is set to `nil`, then the `Resources` folder is used.
+     */
     let dataDirectory: String?
     
     func customDataDirectory(or publicDirectory: String) -> URL {