Reduce bundle size

[timedtext]

Importing in this way can reduce the bundle size when it is needed to package into a single file.

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[mcollina]

lgtm

[Fdawgs]

@timedtext Do you have a link to any documentation regarding this?
Thinking about hunting down similar code in other Fastify repos.

[Uzlopak]

actually I dont like this, because it makes us dependent to know on the file structure of the dependencies.

[gurgunday]

Here's a place that partially talks about it: https://nodejs.org/api/packages.html#subpath-exports

Subpath exports can point to smaller .js files

A known example is require('fs/promises') vs require('fs').promises, the former can point to a file that only has the async functions thus reduce bundle size

[Uzlopak]

Problem is, that if the package itself changes its internal file structure, we would need to change the path in our files too.

[Fdawgs]

Problem is, that if the package itself changes its internal file structure, we would need to change the path in our files too.

Good point, maybe just the builtins like @gurgunday highlighted?

[Uzlopak]

builtins usually dont need to be bundled.

[timedtext]

Problem is, that if the package itself changes its internal file structure, we would need to change the path in our files too.

Maybe we can write a unit test to make sure we can sync in time when the file structure changes.