i don't use create-react-app so i don't know, what do you mean by "show eslint results instantly"? perhaps you are looking to next lint (npm run lint)

every time I update the code, I want it to show eslint warnings in the console.

react-scripts normally has such an eslint error, so it always shows it, not when you run build or eslint

You meant showing in the dev server? That's not possible unfortunately

I understand this is sad, I hope such a feature will be added soon

@joulev Why is it not possible to show eslint errors while running dev?

I'm trying to figure out how to see the same eslint errors as I would in production (i.e. when running npm run build) during development.

When I run npm run lint src, it just returns ✔ No ESLint warnings or errors.

Why is it not possible to show eslint errors while running dev

because they didnt implement it. you are free to contribute an implementation https://github.com/vercel/next.js