Usually software architecture is not language-dependant, so your knowledge from Java could be used here. For example, you can do hexagonal architecture in NodeJ

Usually software architecture is not language-dependant, so your knowledge from Java could be used here. For example, you can do hexagonal architecture in NodeJS. All of what you learned about exceptions can also be applied here. Probably most of what you learned about static typing too, if you work with TypeScript. I think another part of learning JavaScript is forgetting what you learned in other languages and embracing JavaScript. At work most of the JS/TS code is namespaces and plain functions, with the occasional object when that makes sense. We don't use much the dynamic nature of the language in application code, but for testing we use it a lot. For the performance part, I agree, it's hard to find resources. Part of it is because JS is "good enough" for most server-side software: the language is fast and asynchronous IO helps a lot. Most high-level advice is about being nice to the JIT: write code as if it was statically typed, let the JIT make easy assumptions and don't break them (objects that don't change, arrays used as arrays). Part of it may also be because the V8 team is constantly hard at work to improve performance. Their blog (https://v8.dev/ https://v8.dev/) is a great read, I learned a lot here. There's another high-level advice that works everywhere: try to make a stateless app, so that scaling horizontally is easy.