[angersock]

I really hate the framing here...there are senior devs who use NodeJS.

It's not like being a senior dev in language or framework A magically means you're a complete and hopeless noob the second you switch.

Sure, you'll have rough patches, but being a good senior dev specifically implies that you know yourself well enough to handle such transitions.

[davismwfl]

This seems accurate to me. A senior dev can move between tech stacks and not loose their title. At the same time, to me that same senior dev will be the one that recognizes when they are still learning a tech stack and won't be afraid to ask questions of anyone that might know, regardless of that person's title.

I think the difference is you can be a senior developer, but be learning a new stack or learning a particular technology. The key difference is you will recognize the patterns and practices that generally make code more stable, maintainable etc. A person with 1-2 years of total experience will make more mistakes learning any technology than a person with 10 years of experience.