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 # Changelog
 
+# v0.3.1
+
+### Fixes
+
+- **Tech tree Auto-arrange no longer takes the server down**: on a large tree, Auto-arrange and Save positions could overload the server and knock it offline. Layout changes now save in one go, so they are fast and safe on any size of tree. When you click Auto-arrange, the canvas rearranges right away and shows a small "Arranging..." indicator while it saves. Dragging and the layout buttons pause until the save finishes, and if a save fails you now get an error in the toolbar instead of it failing silently.
+
+---
+
 # v0.3.0
 
 Personnel gets a real promotion pipeline, ops move through their lifecycle on their own, and the tech tree becomes fully editable on the canvas.