Finished the Loom onsite a few weeks ago and kept notes. Here's specifically what the coding rounds looked like, since I couldn't find clear info going in.
First: there is no take-home or async online assessment. At least not for the senior SWE track in 2026. The phone screen has a 30-minute code component after a 15-minute intro/convo with the hiring manager. The onsite has two dedicated 45-minute coding sessions.
Phone screen coding: CoderPad, shared live. Problem was on the medium difficulty end. Array manipulation, nothing exotic. They said you can use any language. I used JavaScript because it's what I know best and nobody cared. They did ask me to talk through my reasoning continuously, not just code silently.
Onsite coding rounds (two of them): Round 1: a medium-ish problem on string parsing. Think parsing a structured text format with edge cases. Not a classic Leetcode problem verbatim but similar pattern to medium Leetcode problems. Round 2: something involving trees and recursion. Again medium territory. They gave me a hint when I got stuck on the base case, which I took as a good sign that they weren't just waiting for failure.
No hard Leetcode problems in my loop. But I wouldn't assume you can skip hard prep entirely, this is a data point of one.
What they seemed to care about: Clean code, not just working code. Variable names, function decomposition, that sort of thing. Communicating before you start coding. One interviewer explicitly said "walk me through your plan first." Handling edge cases proactively rather than waiting to be asked.
Test coverage wasn't a formal thing but both interviewers asked me to trace through an example myself before calling it done.
Feel free to ask if you want specifics on the format.