This article has been inspired by this article and by the official documentation of Mozilla Firefox syncserver.
After reading the article by Mirabelette, I thought it would be nice to have my own syncserver, the only difference is that:
I run DragonFlyBSD I want a PostgreSQL database as I know how to make backups of it. That led me to two different steps :
building syncserver under DragonFlyBSD making syncserver use PostgreSQL as its database instead of SQLite.