I haven't seen much of Stencil as of yet.
It's in the same space as Svelte, but Typescript native and compiles into spec-compliant web-components by default.
Been using it since Beta without a framework (or using stencil as the "framework") and it's been pretty amazing. It feels more like I'm writing Vanilla JS with Typescript support.
It supports the major frameworks too... I just got tired of chasing the upgrade cycle.
I can have beta components I built a year ago sitting on the same page with 1.x components from today, and if the old component ain't broke, I don't have to mess with it. I just upgrade when I need it.
I have pretty much everything I need from a framework, but I don't pass any "framework" code to the users, just the compiled vanilla WC.
Built by the Ionic team and they built Ionic V4 with it (but ionic isn't required for it) and I know Apple used it for the new Apple music, and (anecdotally, through friends) a few other large companies are evaluating it...
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