A shocking end to 2015 ... Birdman and Lil Wayne partied together at Drake's New Year's Eve bash!

The crew raged in Miami at E11even nightclub. 

It's hugely significant ... Lil Wayne has been on the Birdman attack for more than a year, claiming Daddy screwed him out of millions of dollars.  Wayne sued Birdman to fly the Cash Money coup.

It's unclear if the pic is evidence of a peace treaty or just a good party.