Thanks for the good info about the DT project. I want to say that even though I'm not personally a fan of TypeScript I really appreciate the work of you and everyone else who has contributed to the DT project. I know from my previous work on OSS how much work that can be.

My only experience using DT was through Nuget so I didn't realize you had the semver postfix. I suspect that like me most .NET devs will go to Nuget first, so I personally would place a high priority on getting semver in Nuget, but I understand that there are lots of other important things too.

My suggestion would to make including a semver part of your quality requirements so that at least you have a record of what version they were working against when they made the type definitions.

I hadn't realized the interdependent library testing/validation. You really are in a pickle about git branching/tagging and not being able to have separate repos. Problem is, the side by side definitions for different versions makes it difficult to merge fixes across versions (as compared to say a different branch for each version of the library). I think this is something that needs to be thought about long and hard. Could you use git submodules or subtrees to do what you need? Perhaps have each library in its own repo but then have a repo that pulls them together and has the interdependecy testing? That way most contributors could work in the repo for the project they care about and only a few contributors would worry about the combined one?

Thanks for sharing your experience with TypeScript and what is good about it. It's just not possible for me to address everything bad & good about a language in one blog post, so I have to focus on what's relevant to the point I am trying to make (in this case why I don't personally think TypeScript is the answer to JavaScript).

I absolutely agree that meshing with the JS ecosystem is of critical importance and Dart just doesn't have that the way TypeScript or CoffeeScript does.