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They haven’t backed off from global inference. They did move to require you to type collections, but methods are not inferred at definition but rather at invocation and it happens globally.

There is no solution really. If you want a language to feel like it is dynamically typed but actually has types, something gotta give, and in this case it is compilation times. And it gets quite high fast.

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> They haven’t backed off from global inference.

You might know a lot more than me about the subject, so feel free to correct me, but I think it used to be truly global inference - as in you were expected to write the whole program with no annotations. But now you're required to annotate instance and class variable types, because compile times were becoming intractable.

It is still global. Typing collections and instance/class variables help, you can optionally type methods, but anything that is not explicitly typed is going to be inferred during invocation and that needs to happen based on all callers in the whole program. Reducing the amount of type variables do not eliminate the global behavior.

In contrast, local inference considers a predefined context, such as the current module or class, and is much faster, easier to cache, etc.

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