European tech salaries are famously lower than US salaries.
Southern Europe is even worse. I was offered a role of Senior/Lead engineer (with over 10 years exp) for "maximum salary of 45k Euro". And was told by their recruiter that this is considered high for Spain.
£90k for a dev job isn't that low, even in London. Unless it's very senior, you'll be paid more than in most other sectors (probably same as in finance).
Really depends on the location within Spain like other Euro countries like the UK. In Barcelona or Madrid a Lead engineer at the right firm will be hitting around 100-110k euros.
Southern Europe is even worse. I was offered a role of Senior/Lead engineer (with over 10 years exp) for "maximum salary of 45k Euro". And was told by their recruiter that this is considered high for Spain.