Ask HN: Cities underserved by tech jobs? (Europe Edition)

This question was asked last week and basically asked, which tech cities in the US are hidden gems and often overlooked. Atlanta and a number of other cities were posted and at least how the commenters described them, they sounded like very liveable places.

Which got me thinking, are there overlooked tech cities with good pay, affordable living etc. in Europe?

tldr: Cheap, good tech cities to live in Europe?