The salary isn't that out of line for a mid-level developer nationwide, but yes I would expect it to be higher for the southern location. They could justify the salary if it was fully remote.
replyBear in mind there is a 23.7% pension contribution from the employer, so it's a roughly £62-70k total comp for a mid-level role.
Edit: Actually though, in reality I would expect a salary bump to work in the public sector to encourage one to put up with the terrible working enviornment with all the bureaucracy.
As someone who has recently joined the civil service as a software developer I have to say the working environment in the organisation I joined is pretty great. Salary is not high, but pension, holidays, working hours and flexibility are all very good.
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