Looking through their API docs, one of the things that I noticed is that they added a transaction log ("delta" field), which IMAP doesn't have: https://www.nyla

Looking through their API docs, one of the things that I noticed is that they added a transaction log ("delta" field), which IMAP doesn't have: https://www.nylas.com/docs/#deltas https://www.nylas.com/docs/#deltas Having a server communicate with IMAP (which is slow), cache the results, and export a more efficient/log-structured alternative probably makes syncing client computers much faster.