diff --git a/README.md b/README.md
index a344b50..de66bf9 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,13 @@ hydrated
 
 a low profile split ergonomic keyboard with a trackpad and swappable "cores".
 
+```mermaid
+flowchart TD
+    A{Host} <-->|USB| B{{Core}}
+    B <-->|i2c| C([Head])
+    B <-->|i2c| D([Head])
+```
+
 
 screenshots
 ---