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0 pointstylerhou2y ago0 comments

Google uses a fair number of external dependencies. But Google imposes a fairly heavy cost to add a new dependency. You (and usually your team) has to commit to supporting updating the dependency in the future (only one version of a dependency is allowed at any given repo snapshot), and fixing bugs. Often it is easier just to write code yourself for trivial dependencies (nobody is using left-pad!).

Adding a dependency also generates a change list (because dependencies are vendored), and so the normal code review guidelines apply. Both the person adding the dependency and the reviewer should read through the code to make sure that the code is in a good state to be submitted, like any other code (excluding style violations). Small bugs can be fixed with follow up CLs. If the author/reviewer doesn’t understand e.g. the security implications of adding the dependency, they should not submit the CL.

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lopkeny12ko2y ago

I've talked to many Googlers over the years, and your summary is consistent with what I've heard before, so I don't think you're lying. But this is still the most insane dependency managenent scheme I've ever heard of. Is Google truly so far up their own ass that they make it harder to pull in a third party library than write the code in-house? Why is Google so allergic to using a package manager like every other software project in open source?

You depend on any modern JS library like Babel or Webpack and it pulls in a dependency tree consisting of hundreds of packages. I cannot fathom that the expected and approved workflow is for someone to check in their node_modules directory and be expected to security-audit every single line, and "own" that source code for the entirety of Google. Sounds absolutely insane.

Not to mention needing to hand-audit that every transitive dependency of Babel and Webpack works with every other module in the repository, because of the one-version policy that exists for some "good" reason.

remus2y ago

> But this is still the most insane dependency managenent scheme I've ever heard of. Is Google truly so far up their own ass that they make it harder to pull in a third party library than write the code in-house? Why is Google so allergic to using a package manager like every other software project in open source?

In the context of working in a highly sensitive business environment, I think the typical defaults of most package managers are way more insane than the practices being described (vendoring, auditing etc.) I think google is just being upfront about the costs of dependencies, which are often hidden by package managers. At the end of the day it's just code written by other people and using that code blindly has huge risks.

I think this is pretty context specific though. Do I care if my hobby project goes down for a day because a dependency auto-updated and broke something? Not really.

atq21192y ago

> Is Google truly so far up their own ass that they make it harder to pull in a third party library than write the code in-house?

From the descriptions in this thread, pulling in a third-party library is still far easier than writing the code in-house for them.

At least, it sounds to me like for adding the kind of example you gave, their process for adding the dependency is on the order of person weeks or in the worst case months, while writing the code themselves would be on the order of person years or decades.

UncleMeat2y ago

I think it is interesting how both possible stories get criticized.

Option 1. Google has minor but uninteresting restrictions on pulling into //third_party: "well these audits are obviously useless because nobody reviews the code that closely."

Option 2. Google has very strong restrictions on pulling into //third_party: "this is so far up its own ass and completely unproductive."

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