`typed-builder` and `derive_builder` are both used

[Xuanwo]

Should we stick to one builder crate instead?

[liurenjie1024]

I'm in favor of using typed-builder only, but the problem is that its type is not clear, which maybe a problem when you want to save a builder in your struct.

[Xuanwo]

cc @liurenjie1024, is this issue still valid? I can help address this.

[liurenjie1024]

Seems it still exists.

[Xuanwo]

Do we really want users to store builder in struct?

[liurenjie1024]

Do we really want users to store builder in struct?

Good question, I think we should have some abstractions like Factory to do that if necessary. But I'm not sure about all details.