[brianvaughn]

> From the outside, having seen Fiber slated for release in 16.0.0 and, being pushed back to an unknown 16.x release, and then being pushed back to 17.0.0, it seems like you had not anticipated the extent to which the core React API had to be changed to enable the async renderer.

"fiber" was the code name for the rewrite that was released as version 16. Async rendering is a feature that we've been working on adding- (which the "fiber" rewrite was done to support). We've known that would take some time, mostly due to the fact that we want to gradually migrate old apps (as much as possible). :)

We're also working on other cool, related efforts- like a compiler (https://twitter.com/trueadm/status/944908776896978946) and proper built-in support for async-data, dubbed "suspense" (https://reactjs.org/blog/2018/03/01/sneak-peek-beyond-react-...).

[Vinnl]

> We're also working on other cool, related efforts- like a compiler (https://twitter.com/trueadm/status/944908776896978946)

That sounds like it could bring a lot of benefits. Would, and if so how, that affect people using TypeScript?

[brianvaughn]

I don't think we know enough about where compilation will end up to comment much. I wouldn't expect TypeScript to be negatively affected though (since it compiles to JavaScript). So far, the problems we're noticing are from certain coding patterns or practices within components. However we deal with these (whether we add new lifecycles or encourage alternate patterns, etc) it should hopefully apply equally to JS/Flow/TypeScript.

[Vinnl]

Obviously, but thanks for the tentative impact estimates :)