I’ve used Lightcast (prev EMSI) data before to look at skills in demand / job posting trends. you have to request access, but they have a free API and the data was impressively clean in my experience, although it was a few years ago.
Less sure on Poland. That would cover demand, and then maybe you could look at average job posting age/time to fill as a proxy for supply and ease of hiring?
They definitely cover Go in Canada (here’s a preview page): https://lightcast.io/open-skills/skills/ESA5839C44D0970CF79F
Less sure on Poland. That would cover demand, and then maybe you could look at average job posting age/time to fill as a proxy for supply and ease of hiring?