Can confirm that 120-150 is mid-range base for a senior dev or devops roles in London; not just for fintechs in the City but from post A-round startups in Shoreditch and established companies around town. I have seen some outside IR35 contracting roles start to exceed £1000 per day in the job description (so you know a canny operator can be getting more for that contract.). 8-12 months ago everyone was holding their breath and not hiring while they waited to make sure they survived the Covid lockdowns, but now that things seem to have recovered it has become a sellers market as everyone tries to catch up on a backlog from not hiring over the previous six months.