README.md in gds-warmup-controller-0.0.2 vs README.md in gds-warmup-controller-0.1.0

@@ -1,4 +1,9 @@
+Adds a /warmup route to a rails app to provide a generic endpoint to use with
+the PassengerPreStart directive.
+
+Please don't rely on this code outside of Government Digital Service - it may
+well go away if we switch away from Passenger.
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