You removed the API and bot_upgrade related functions. Even if they are useful, they were not essential and we will be able to add them back easily later on so it's ok for me.
Regarding your comment on db.init() that could harm performances. It is true that open db connection at every request is expensive, this is why we highly recommend connecting to a local db connection pool (like pgbouncer for example) in order to make this call inexpensive performance wise.
what IDE are you using and with which configuration (tabs vs spaces etc...). We should make sure we use the same settings.
Add classes User and Message. Rewrite navigation.rb Fix few bugs