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Back in the pre-Disney days, there was a wealth of canon works of various stripes that dealt with the Star Wars galaxy after the events of Return of the Jedi. From the Dark Forces / Jedi Knight / Jedi Academy games to the books (I had a personal preference for the X-Wing series).
Since the relegation of all of this to Legends status, what works remain in canon to cover the time period between Return of the Jedi and The Force Awakens?
I am aware of Aftermath (which is somewhere on my future reading list). I'd be specifically interested in any that deal with the development of the New Republic.