Some notes on upgrading to 1.0

README.md

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+**Please see a guide on upgrading to 1.0 at the end of this README.**
+
 # Rationale
 
 There are several available proxies for Telegram MTPROTO available. Here
 | `crashes`                        | number  | An amount of crashes in client handlers                   |
 | `traffic.ingress`                | bytes   | Ingress traffic from the start of application (incoming)  |
 | `traffic.egress`                 | bytes   | Egress traffic from the start of application (outgoing)   |
-| `replay_attacks`                 | number  | A number of prevented replay attacks.                     |
+| `replay_attacks`                 | number  | The number of prevented replay attacks.                   |
 
 All metrics are prefixed with given prefix. Default prefix is `mtg`.
 With such prefix metric name `traffic.ingress`, for example, would be
 
 [Prometheus](https://prometheus.io) integration comes out of
 the box, you do not need to setup anything special.
+
+
+# Upgrade to 1.0
+
+Version 1.0 breaks compatibility with previous versions so please read
+this chapter carefully:
+
+1. mtg now uses subcommands. Please use `mtg run` instead of just `mtg` to run
+   a proxy.
+2. Options which set host and port separately were removed in a favor of fused
+   host:port options.
+3. Own stats server was removed. Prometheus endpoint is moved to default stats
+   endpoint.
+4. It is possible to connect to this proxy only with a secret which was used to
+   run it. So, no backward compatibility of clients.