Can I rely on --experimental_downloader_config being available in the future?

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Person 261370

Mar 20, 2024, 8:45:13 PMMar 20
to bazel-discuss
My team is considering using the flag/feature --experimental_downloader_config but there are concerns with the "experimental_" prefix.

I understand from

>  APIs and behavior guarded by an --experimental_* flag can change at any time
> Never run production builds with --experimental_* or --incompatible_* flags.

I also see that bazel team is using the flag in their own repo, and that it is talked about in some blog posts.  

I understand that the "experimental_" prefix reserves the right for the development team to change the behavior/functionality of this feature at any time.  I think that's great to ensure stable features get developed and are supported properly.  

I'm just wondering if anyone here can provide any gut check that this feature will remain in some form or another.  The scale I had in mind was something like below:
  1. The future of this feature is uncertain.  This feature could get removed in the near future (or we reserve the right to remove it)
  2. This flag/feature is important, and there may be some behavior changes, but the feature provided will remain, but some use cases may be dropped in the future.
  3. This flag/feature is important, and there may be some behavior changes, but the feature provided will remain (for example, if there are changes, the majority of folks using this experimental flag will likely be able to migrate to the more stable version of this feature) 
  4.  This feature will definitely get promoted to a stable feature ("experimental_" prefix removed). And no behavior is expected to changed.
I was hoping someone could say that the feature is in the 3.0-4.0 range.  I'm not holding anyone to this number - I just wanted to get a general sense for how "mature" people believed this feature/flag was.

Thank you for your time!

Alexandre Rostovtsev

Mar 20, 2024, 9:49:03 PMMar 20
to Person 261370, Chi Wang, Xudong Yang, bazel-discuss

See for some discussion about what would be needed to mark the feature as non-experimental.

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Xudong Yang

Mar 21, 2024, 11:23:25 AMMar 21
to Alexandre Rostovtsev, Person 261370, Chi Wang, Xudong Yang, bazel-discuss
This specific flag has been fairly widely adopted in the ecosystem, so I think it's definitely safe to say it's a 3 or 4.

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