Add a warning about 1.5 and traefik

README.md

@@ -1,3 +1,15 @@
+<aside class="warning">
+**Be very careful when using `master`**, especially if you are currently running
+`1.4`, development of version `1.5` includes refactoring the frontend and
+authentication mechanisms. At best your server will stop working, at worst you
+could expose your data to malicious attackers!
+
+**Do not start using `traefik`** as a frontend server. Traefik was first tested
+to replace nginx because certificate generation was a nightmare. As we are in the
+process of completely rewriting the frontend and authentication interface, it will
+probably be deprecated before `1.5` is out.
+</aside>
+
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