Probably the biggest thing is that it translates a traditional document-based data structure (mailboxes via IMAP) into a stateless, streaming transactional data structure. This allows N1 to be way more efficient and faster, and only load about 2% of the total data in your mailbox.<p>The sync engine is essentially an abstraction layer for IMAP&#x2F;SMTP&#x2F;MIME&#x2F;etc. This architecture has become pretty common in the past few years: Mailbox, Outlook Mobile (Acompli), Spark, Cloud Magic, Gmailify, and many more run similar systems. Although as far as I know, we&#x27;re the only one who has open sourced our backend.:<a href="https:&#x2F;&#x2F;github.com&#x2F;nylas&#x2F;sync-engine" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;nylas&#x2F;sync-engine</a><p>We actually released the API layer before N1, and lots of developers use it for their own apps and pay us to run the infrastructure. If you&#x27;re curious, the full docs here: nylas.com&#x2F;docs&#x2F;platform<p>You can pretty easily set up the sync engine and run it yourself, either locally or on a VPC, and connect N1 to that instance. We do this ourselves when developing, and it&#x27;s the best way to have 100% control over the entire stack. More info here: <a href="https:&#x2F;&#x2F;github.com&#x2F;nylas&#x2F;N1&#x2F;blob&#x2F;master&#x2F;CONTRIBUTING.md#running-against-open-source-sync-engine" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;nylas&#x2F;N1&#x2F;blob&#x2F;master&#x2F;CONTRIBUTING.md#runn...</a><p>There&#x27;s a bunch of community developers than hang out in our chat room and can also give you some tips for getting started. You can join that here: <a href="http:&#x2F;&#x2F;slack-invite.nylas.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;slack-invite.nylas.com&#x2F;</a>