On one hand I agree with his sentiment. But being a co-creator of redux is not really a good argument. I would probably flat-out reject members of the core redux team when hiring, considering redux's design.

What's wrong with the design of Redux?

It is not composable. I.e. you cannot use one "redux-application" within another one.

Some ideas of redux are great, but the execution could have been much better. I think lack of experience (maybe also related to Javascript) is the reason.

Why isn't possible to embed one Redux application into another? You can have multiple Redux stores so I don't see how Redux applications are unable to be composed.

I _think_ this demonstrates something similar to what you're talking about: https://redux.js.org/recipes/isolating-redux-sub-apps

I'm also curious which parts of Redux weren't executed well, especially considering how small the library is.

Thank you for your link. I think the link captures it quite well. It says:

> These <SubApp>s will be completely independent. They won't share data or actions, and won't see or communicate with each other.

and

> This pattern is not recommended for parts of the same app that share data.

This is precisely where it gets interesting. Composition is important to combine things without these things knowing that they will be combined in advance and having to change them.

So imagine there exists a redux application that shows a dashboard which lists sales within a timeframe. Now I build a new redux application that wants to use two of the existing redux applications next to each other, using one to show sales for last year and one to show sales for this year, using the same timeframe (months/days) but for different years. This is a very very simple case of composition, but it becomes tricky fast.

Question: how do can I align the timeframes within the two sub-applications? I want to make it so that if the user changes the timeframe within one of the subapplications, it should translate to the other one and vice versa. Can I do this _without modifying the code of the sub-applications_?

Obviously the author is productive on a "real world business engineering team" considering they work for Facebook. Since you seem to have a lot to critique about the post and the author, maybe it's worth putting in that effort into reflection and self-criticality as well.