PEP 751: one last time

I’m pleased to announce that PEP 751 is accepted. Congratulations to @brettcannon, and to everyone who has participated in something like 4 years worth of discussion and design. It’s been a long road, but I’m confident that the result will be a big step forward for the packaging ecosystem.

I’ll note that this is full, final acceptance, not provisional[1]. I’ll make a separate post going into more details, but I don’t think there’s any advantage in provisional acceptance here - it will only introduce further uncertainties and delay before people can confidently start implementing and using the new standard.

This standard wouldn’t have been possible without Brett’s hard work over many years. The community owes him an immense debt of gratitude for all the work he has put in on this proposal and its predecessors. But a standard like this is never the work of one person, and everyone who has participated in the discussions along the way should be proud of what we’ve achieved here - it’s a fantastic example of what community involvement can deliver.

We have now laid the groundwork, but there will still be a lot of work for tool maintainers to implement lockfile support throughout the ecosystem. The design is very flexible, and leaves a lot of room for tools to experiment and innovate, both in terms of the UI they will provide, and the capabilities they will use to deliver functionality - in particular for lockers, having this standard is merely the first step in a process of integrating it into their existing (custom) solutions.

One area in particular where the standard is known to be limited is in its support for monorepo-style development workflow. The “workspace” model of uv is an example of this. I think monorepo support is somewhere the ecosystem as a whole needs to be able to innovate and experiment on, and lockfile support is merely one aspect of that. In particular, I don’t think that we’re ready for standardisation in this area, and while that gives us some rough edges for the moment, an update to the lockfile standard at a later date when we have more experience with monorepo support will be a better outcome than trying to solve the problem in the abstract right now.

Thanks again Brett, and enjoy all the extra free time that you’ll have now :slightly_smiling_face:


  1. in spite of statements I’ve made previously in these discussions ↩︎

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