Build/Metadata Hook

[ninoseki]

Summary

I think it would be better if uv's build backend had the same hooks as Hatch. The build hook and the metadata hook.
Could you consider support them in the build backend, please?

Example

• Build hook: https://hatch.pypa.io/1.1/plugins/build-hook/
• Metadata hook: https://hatch.pypa.io/1.1/plugins/metadata-hook/

[zanieb]

Plugins and dynamic metadata aren't in scope for the build backend yet, they add a lot of complexity.

[zanieb]

Can you share more about your use-case?

[ninoseki]

Can you share more about your use-case?

• Build hook use-cases:
  • Setting a version based on VCS:
    • https://github.com/ofek/hatch-vcs?#build-hook (2.3k files)
    • https://github.com/ninoseki/uv-dynamic-versioning/blob/main/docs/version_source.md (0.5k files)
• Metadata hook use-cases:
  • Setting dependencies based on requirements.txt:
    • https://github.com/repo-helper/hatch-requirements-txt (0.5k files)
  • Setting dependencies dynamically based on VCS:
    • https://github.com/ninoseki/uv-dynamic-versioning/blob/main/docs/metadata_hook.md:
      • It's used by a very few projects. But a popular project like Pydantic AI uses this.

[matdibu]

I'm currently using Hatch in a lot of projects exclusively for codegen (grpcio-tools) via tool.hatch.build.hooks.custom

is this something that the uv_build backend is going to provide at some point in the future? thanks

[gwdekker]

Another usecase is for polylith - a monorepo tool for python. The hatch based build backend allows for letting it hook into the build process, while not having hooks available makes it need the workaround doucmented in the polylith docs for maturin: DavidVujic/python-polylith#353

[brant-qai]

The dynamic versioning in particular is a very common use case. I have to either use hatch+uv-dynamic-versioning or setuptools+setuptools_scm and the only reason I'm still making use of those backends at all is dynamic versioning.

The most fire would be for dynamic versioning from VCS to be builtin to UV; that would really give it that one-stop-shop feel (the same way uv format utilizing ruff under the hood does. I prefer not to manage a big suite of extra tools.

[twsl]

Missing support for dynamic versioning is the only reason preventing me from switching away from poetry. Would love to see a build hook

[ninoseki]

Missing support for dynamic versioning is the only reason preventing me from switching away from poetry.

ICYMI uv can handle it already along with Hatchling build backend.

[pygarap]

Missing support for dynamic versioning is the only reason preventing me from switching away from poetry.

ICYMI uv can handle it already along with Hatchling build backend.

@ninoseki People want to use dynamic-versioning, together with the uv build backend, not with any other build backend.

[etienne-monier]

Hi,
Another use case: I need to build a javascript bundle to be served by my fastapi application. This is done at build time.