Topic: On what to write

Let's consider. It seems to me that in  to year it is necessary to provide following possibilities: 1. Operation from a DB, migrations 2. The http-server and the client, the socket-server and binary protocol 3. in-memory a DB for caches and configs 4. Dialogue between nodes of servers 5. Monitoring of loading and Mb collection of statistics 6. Internal tasks under the schedule 7. Tests 8.  and update of separate subsystems On what it turns out is better?