diff --git a/README_DEVELOPER.md b/README_DEVELOPER.md
new file mode 100644
index 0000000..5976fde
--- /dev/null
+++ b/README_DEVELOPER.md
@@ -0,0 +1,19 @@
+# Bahmcloud Store – Developer Documentation
+
+This document is intended for developers and contributors.
+
+## Architecture
+
+BCS consists of:
+- Installer Add-on
+- Core Integration
+- Store Index
+
+## Code Structure
+
+See custom_components/bahmcloud_store
+
+## Rules
+
+- Code in English
+- No breaking changes without version bump