Machine learning specialist: US 108k, Canada 53k (49%)
Embedded applications/devices developer: US 100k, Canada 53k (53%)
Systems administrator: US 90k, Canda 49k (55%)
Doubling your salary by moving south across the border is a very tempting option, especially considering that NAFTA makes it extremely easy to do so. No need to wait for an H1-B, just show up at the border with job offer & credentials in hand, assuming you've graduated college. TN visas are instant and infinitely renewable.
[1] https://stackoverflow.com/insights/survey/2017#work-salaries...