Rookie of the year (answer)
Awarded for the best answer by a user who had not posted an answer before 2016. Note that the user may have posted challenges before 2016. SEDE query for such answers, ordered by score.
Nominations:
Radiation Hardened Quine by ais523
Nominated by Martin Ender
ais523 started contributing in mid-November and has since posted 139 answers and 10 challenges as well as very valuable contributions on meta. The overall quality of their content is absolutely outstanding, and I'm having a really hard time picking a specific answer to nominate (this Cubix quine would also be a decent candidate). I've chosen the answer above because a third-order radiation hardened quine in a non-esoteric language is a very impressive achievement and the answer also comes with a great in-depth explanation.
##Golf you a quine for great good by udioica
Golf you a quine for great good by udioica
Nominated by DJMcMayhem
Not a lot of people on this site golf in vim, so I used to think I was the king of vim-golf on this site. I wrote a 17 byte vim-quine and challenged anyone to outgolf me, thinking I was safe. Boy was I wrong.
Udioica noticed the challenge, and rose to it, golfing a whopping 6 bytes off of my solution on the first day they ever used PPCG.
Build a digital clock in Wireworld by niemiro
Nominated by Peter Taylor
This is niemiro's only answer on PPCG so far, and claims to be their first Wireworld circuit too, but it is most definitely ambitious. The answer includes not only an animated GIF of the circuit in action but also a detailed breakdown of its construction.
A rather knotty conundrum by ais523
Nominated by Peter Taylor
The only answer at present to a rather difficult question, and an excellent illustration of the importance of choosing the right language for the task.
A Mouse with Dynamite by Ton Hospel
Nominated by Dada
Ton Hospel is someone who needs no introduction. He is one of the best Perl golfer in the world, has been so for pretty much as long as Perl golfing is a thing, and his solutions are always innovative, unexpected and short. And as it happens, he only joined PPCG this year. His code to solve A mouse with Dynamite is a good example of his skills, and definitely one of the best golfings I've ever seen (and it comes with a very detailed explanation).