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Comment by ziggus | Hacker News Reader

But at some point, isn't the hand-picked approach going to result in the same morass of version dependencies on any site of moderate complexity?

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Ideally you would choose dependencies with minimal dependencies of their own (very few if any common dependencies), so you have a manageable number of versions and near complete freedom of choice of those versions.

And ideally, you'll wrap them too. In what is often called "Anti-Corruption-Layers". Often very simple Proxies or Adapters. Consequentially, this makes testing (in isolation) far easier too.

Which also means you'll choose libraries that are decoupled by design because the others are really hard to write such wrappers for.

Sometimes quite useful, yes, though I would strongly emphasize that the goal is not to wrap the entire API of the dependency -- that is pure busywork and doesn't stave off "corruption". Just the (consciously quite minimal) parts you actually need.

I'll usually even add another guard: only add them if the library uses non-domain language.

For example, so that you can say "chargeCard(payment)" in your domain and app, Instead of having to do things like "openAnonCustomer(payment.customerId) && pmt= addPayment(payment.amount, payment.currency) && bookPayment(pmt)" or whatever weird language, order, or transaction boundaries a library uses.

Yes, wrap a useful "flow" for your application, rather than functions. Often I find there is just one flow for a dependency.

Yes, but the whole point is that you don't have to update all your dependencies at once.

Even if you do find yourself needing to update your dependencies, you can do them 1 at a time. This way you aren't stuck with a not building, completely broken codebase for days while you refactor to adapt to new changes.

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