Seniors have a language-independent model of software development tasks such as writing code, testing, debugging, building and publishing artifacts, etc. to work from. They can map that model more or less to any software ecosystem. That model comes from hands-on experience building software, and often takes years to build.

While they are building up that conceptual model of software development, an engineer is also building up knowledge about the _details_ of their first or primary language’s ecosystem, libraries, and tooling. This also takes years, one just doesn’t notice it with the first language because it intuitively feels like “learning programming” since it happens in parallel.

The result is that a senior engineer can be productive quickly in any language, relying mostly on their conceptual model. But to go from “productive” to “mastery” with a new ecosystem is still all the same time and effort it took for the first one.

It is a good comment.

But I am an engineer, I build stuff. I am not sure I want to become Picasso