I've read a large chunk of his Study Hacks blog and two of his books: Straight-A Student and Deep Work. This guy has saved both my academic and professional career. The concepts of deep work, of deep stretches of focused abstract thought to learn complicated mathematical topics, of mastering computer science and academic writing -- these all feel very Ni+Te to me, and definitely appeal to both my 5-wing and my Te's desire for scheduling and order. While I love his work, I also tend to disagree with his advice on only focusing on one or two areas of mastery, which I think points to a difference between my Ne and his Ni.

Just finished his podcast with Lex: https://www.youtube.com/watch?v=y3Umo_jd5AA

Pretty sure he's an IxTJ, he is all about optimizing external metrics that he sets by himself, for himself.

Language-wise he seems to have a preference for the abstract rather than sensory, so I'm leaning towards Ni. He is able to justify Deep Work from multiple abstract perspectives, he sees it as a tool to increase his cognitive capacities in the most efficient way.

I don't think he has Si as an end in itself.

I believe him to clearly be an INTJ, a typing most strongly justified by his book Deep Work. That committed preference for deep work over shallow work, a preference Newport has characterized as his life philosophy, is essentially the bias for Ni over Se. He literally, and quite vocally, advocates for the fullest avoiding of sensory tasks throughout your day. Minor Se impediment in your way? Cut it out. He entirely lacks the interest in sensory states and obligations to be a Sensor, and repeatedly argues for a vision that circumvents them. In place of this, he suggests periodically entering a state of deep, introspective focus to generate the kind of high value ideas that run the world. This seems to be a concrete case for dom Ni - certainly instead of dom Si.

I think we can all agree the Te is clear too.

Clearly ITJ.
He has a strong Ti critic referring to his work with "So Good They Can't Ignore You", skip to 29:10 min where C.S. Joseph talks about Ti critic.
-> How Do ISTJs Compare To INTJs? | ISTJ Vs. INTJ | CS Joseph
https://youtu.be/W4Zy0qw6bfM

Apart from having a sharp memory, he has complex structures in his day to day life; not leaving anything unscheduled. From what he writes in his books, with all the routine and follow-up, it is safe to say that he operates with Si, or has Si auxiliary. Te is quite apparent too.