Pros
Working with some great engineers on problems with challenging aspects like handling significant scaling and a fast-evolving landscape. Some great tooling such as unlimited on-demand replicas of the full stack allowing much easier investigation, debugging & testing. Fast release cadences supported by significant CI pipelines, automation. Lovely offices with nice perks. Flexible working really does mean flexible here, rather than being a codeword for allowing you to do unpaid overtime if you want.
Cons
Engineering is isolated from it's CTO by a layer of non-technical people at VP level. They're not bad people, but it makes for a difficult experience and restricts potential career growth opportunities once you're near the top of the Engineering tree. Salaries are decent, but very widely variable within a role - if you don't want to negotiate hard you are likely to do worse than colleagues more interested in fighting for more.