[Sukera]

There is no rebuttal because nothing much has really changed culture wise. Sure, the various @inbounds issues and concrete bugs that are mentioned in Yuris post have mostly been addressed, but the larger point (that is, "what can I actually expect/get guaranteed when calling a given function?") definitely hasn't been, at least not culturally (there are parts of the ecosystem that are better at this, of course). Documentation of pre- and postconditions are still lackluster, PRs trying to establish that for functions in Base stall for unclear reasons/don't get followups and when you try to talk about that on Slack retorts boil down to "we're tired of hearing you complain about this" instead of trying to find a systemic solution to that problem. Until that changes, I have large doubts about Yuris post losing relevance.

My own efforts (shameless plug, https://github.com/Seelengrab/PropCheck.jl for property based testing inspired by Hedgehog and https://github.com/Seelengrab/RequiredInterfaces.jl for somewhat formalizing "what methods are needed to subtype an abstract type") are unused in the wider community as far as I can tell, in spite of people speaking highly of them when coming across them. I also don't think Kenos InterfaceSpecs.jl is the way forward either - I think there's quite a lot of design space left in the typesystem the language could do without reaching for z3 and other SAT/SMT solvers. I personally attribute the lack of progress on that front to the lack of coherent direction of the project at large (and specifically not to the failings of individuals - folks are always very busy with their lives outside of Julia development/other priorities). In spite of the fact that making this single area better could be a big boon with more traditional software engineers, which are very underrepresented in the community.

[ChrisRackauckas]

There is a culture of well-defined interfaces which are checked at compile time. This is something that was emphasized in recent posts and changes such as:

* New trait systems define the allowed inputs into given solvers in order to enforce guarantees https://sciml.ai/news/2022/10/08/error_messages/

* The SciMLOperators.jl interface clarified operators (https://docs.sciml.ai/SciMLOperators/stable/interface/) * The highest level SciMLBase interface got codified (https://docs.sciml.ai/SciMLBase/stable/) along with the trait systems it requires.

* ArrayInterface.jl (https://docs.sciml.ai/ArrayInterface/stable/) and StaticArrayInterface.jl (https://docs.sciml.ai/StaticArrayInterface/stable/) have dropped fallback definitions and require definition of traits for downstream packages in order for any array types to be allowed into package functions

* SciMLStyle (https://github.com/SciML/SciMLStyle) came into existence and defines a style which avoids any of the behaviors seen in the blog post.

* Julia came out with package extensions in v1.9 (https://www.youtube.com/watch?v=TiIZlQhFzyk) and with the interface checking, implicit interface support was turned mostly into explicit interface support where packages and types opt-in via defining traits (this is still continuing to evolve but is mostly there).

Given all of these changes, most of the things in the blog post would now error in many standard packages without someone explicitly defining interface trait functions to allow an object in that doesn't satisfy the interface which it's claiming to. Of course, not every person or every package has changed, but what I described here are major interface, style, and cultural changes to some of the most widely used packages since 2020.

[Sukera]

> with the interface checking, implicit interface support was turned mostly into explicit interface support where packages and types opt-in via defining traits (this is still continuing to evolve but is mostly there)

What interface checking? Base doesn't provide any such facilities. Package extensions are still ad-hoc constructions on a package by package basis; there is little to no consistency.

> Of course, not every person or every package has changed, but what I described here are major interface, style, and cultural changes to some of the most widely used packages since 2020.

And none of that has landed in Base, none of that is easy to find out about/discoverable for non-SciML users. SciML is not all of Julia, and certainly not Base or packages outside of SciML. Please don't frame this as if SciML was the only thing that mattered here.

[ChrisRackauckas]

Yes it has not landed in Base, but you're acting like there has not been a general cultural changes. I showed, with receipts, that many of the most widely used packages in the Julia ecosystem have adopted new infrastructure, systems, and tooling to address these problems in the last 3 years. With SciML and JuMP both having adopted such systems, this accounts for roughly 50% of the top 100 most starred Julia packages according to current metrics (Nov 20 2023), with many of the packages not doing this largely being interface packages (plotting, notebooks, and language interop, if you account for those not having this issue it's closer to 2/3 of the top 100 most starred packages). I also want that number to be 100%, and the compiler team is having weekly discussions with us about our needs given that there are now successful parts of the ecosystem to model this tooling based off of, and so yes it can get better and we need to keep improving. But to claim that no shift in culture has occurred is implying that all of this doesn't exist, even though we can point to the receipts.

[Sukera]

50% of the top 100 most starred, i.e. used, packages are not representative of the entire community. Not to mention that the vast majority of those SciML packages is developed by a relatively small group of people, compared to the rest of the ecosystem. If all a potential user cares about is SciML, good for them! I've repeatedly said that users not looking for SciML are left behind.

Yes, SciML is doing good. I'm not denying that, and never have. Still, the rest of the community/package ecosystem is not good at catching up - which is what I'm criticizing.