[laurent123456]

I think a developer who does that is doing a disservice to the company they are working for. If I start looking at a project and see a bunch of outdated packages that have been copied and pasted there and tweaked who knows how, I quit right away. Not to mention that these packages most likely have various unpatched security issues.

And if the package is not "small enough", I guess it means it needs to be re-implemented from scratch? If a company is happy to pay you for that (and is aware of it), why not, it's fun actually, but not very productive.