I would be very interested in how you did this / where you ended up. Feels like an impossible task every time I consider it.

There’s been a large uptick in immigration from the US to Ireland; almost ten thousand last year. In general, people would do this via employment; software engineers and similar would generally qualify for a critical skills permit. For critical skills, after two years on a stamp 1 visa (tied to a specific employment) you can move to a stamp 4 (not tied to specific employment). After five years working in the country you can apply for citizenship.