happy-dom VS piscina

Next we’ll install Vitest and happy-dom to the project by running:

JSDOM and happy-dom for DOM and browser API mocking

https://github.com/capricorn86/happy-dom/issues/618. Looks like some work was merged recently.

I think you mean jsdom. You can try Happy DOM

Well, I've actually done it using axios + happy-dom.

You may have heard of vite, the slim fast dev server that scored an amazing as deserved 98% satisfaction on the state of js survey 2021. It's creators found unit testing too cumbersome and slow and decided to add their own perspective to the task. The result is vitest: it runs a vite server under the hood to transform the code to test as fast as possible, uses an enhanced flavor of chai to have jest-compatible assertions, integrates DOM mocking using jsdom or happy-dom and even the tiny-spy library that was just built as a separate library to allow for easy reuse is small and compatible with jest.

happy-dom, more lightweight

Workers multi-threading via Tinypool (a lightweight fork of Piscina)

For threading best to use piscina and for clustering best to use pm2 which does not even need one line of code change in Node.js code.

We used piscina at it was quite good: https://github.com/piscinajs/piscina

We used Benchmark.js for benchmarking and piscina as a pool for worker threads. benchmark.js was used to run the same code in 2 scenarios - one using a single thread and one using the piscina pool. The degree of parallelism was passed to the program via an environment variable. The test code is present in worker.js in both the cases.

piscina for managing node's worker threads

One other thing...this passed by in my feeds last week, I’m not an expert in web workers or browser threads etc, but it seems like it might be relevant, so sharing it just in case:

“A fast, efficient Node.js Worker Thread Pool implementation”

https://github.com/piscinajs/piscina

This is by no means a complete list of what piscina can do.... checkout the official docs here.