diff --git a/developer/backends/protocol.md b/documentation/development/protocol.md
similarity index 100%
rename from developer/backends/protocol.md
rename to documentation/development/protocol.md
diff --git a/documentation/index.md b/documentation/index.md
index 3ff2bd3e..e33fb96a 100644
--- a/documentation/index.md
+++ b/documentation/index.md
@@ -44,3 +44,4 @@ title: Spectrum 2
 #### Development
 
 * [Spectrum 2 architecture](development/architecture.html)
+* [Writing backend in any language (also the basic principle of How the backend works inside)](development/protocol.html)