Not sure what your situation is but there are a fair number of options for people who are decent programmers to move to Europe permanently..
My wife and I want to move to Europe from the U.S., however, while I do have 5+ years of experience, I haven't finished my degree...
* Dutch American Friendship Treaty (self employ in the Netherlands)
* Working Holiday visa Irealnd (one year and have to be within a year of school or in school, but if you get a job that sponsors you can stay)
* Germany. Germany is just supposed to be a relatively easy place to get a visa, comparatively. Be sure to look up blue cards.
* Ancestry. Got any history in a European country? Start looking at grandparents' birth certs
Also, a lot of people have mentioned pay. It's true, pay is lower in Europe - in tech. OTOH in other fields there's less of a disparity, or it's higher here. My wife does not work in tech and makes more here (or did before she decided to stay home with our kid).
In Ireland, at least, a normal dev would make very roughly 60(ish), someone versed in ML, etc. closer to 90, and to get to six figures you'd need te be fairly senior. Jobs posted on http://irishtechcommunity.slack.com/ recently have been everything from 40k (junior) to 150k (senior at FB). It's more common to include ranges in job postings here.
Europe is big though and salaries are MUCH different in Portugal than in, say, Finland.
In some places (Norway), you can just look them up - https://www.bbc.com/news/magazine-40669239
I would have recommended Ireland in the past but now, if you're interested, you'd be wise to steer clear of Dublin. Housing has gotten really scarce, but worse than just being expensive it's just really hard to actually _get_ (no surprise given that rent control is bad policy).
If I were looking myself right now the top of my list would be Utrecht, because I love cities where my kid can cycle to school and not die.