That is not exactly a career then. You will only be an expert in a trendy technology. I expect a real senior software engineer to be above the newest trend. I do not want him to understand react. I want him to understand the reactive UI concept (which is applied in React, Angular and maybe a 30 year old tech). I expect him to be capable of learning the newest trend within days and also expect him to understand the 40 year old language and the code style written then. All of that, I do not find in someone who burns himself to become an expert in a trendy tech every 3 months.

React is not reactive, despite the name. Puts your comment in a different light.

That is fair. But I think the point is valid :)

It depends greatly on what you are doing. I've been coding in React for years now, but I _still_ use concepts I learned from Ember, Angular(1), and even non-web tech. Its all UI programming and in the end they all share much more than you'd think. These days I find I can take one glance at newer stuff (say, react hooks) and start getting ideas about how its used, benefits / limitations, even how its implemented, without spending more than 5 minutes looking at it.

Relatedly, constantly jumping into new stuff can actually _hurt_ your progression because if you never master existing tech (find its limits, reading its source), you'll have more trouble seeing the relationships and trade-off's of the new stuff, and spend way too much time just learning API's without gaining any intuition.

What are you thinking of as "legacy technology" though? I know web developers who would put Angular(1) in that category, for instance.

If I don’t remember what I ate for breakfast on the day the code was written, it’s legacy. /s

Angular 1 absolutely is legacy code. My current task is removing all the angular code from our app because the last security test flagged it as a severe issue due to out dated libraries.

> severe issue due to out dated libraries

Which ones, out of curiosity?

Yea - so, three years working on angular 1 starting today won't end your career.

They didn't say "end your career". They said "damage your career".

But the task is to remove the Angular and replace it with something current. List the job on your resume under "something current" rather than Angular, and you're good.