RFC: Multiple bundles

[jurekbarth]

Hi 👋,

Status Quo:
We build one version for each component and a "global" build for common JS/CSS.

Proposed Change:
I would like to have multiple bundles for different targets. As well as entrypoint based bundles.

Why:
For legacy browsers such as IE11 we need a lot of polyfills and transpilation. For modern browsers we could use ES6 modules on the client side, also for dynamically loading new code. This would enhance user experience, performance and so SEO. The need arises even more with web components as they need different polyfills on multiple systems.
In order to get there i think we need two versions: A client side solution and a server side solution. While client side solutions can be implemented everywhere a server side solution would be more preferable. CDNs are shifting in that direction (computation on the edge), e.g. AWS lambda@edge and Cloudflare Workers are heading in here. This could help us to use CDNs and custom bundles.

[timomayer]

i am sceptical about this aproach since if you do it in a consequent way you will end up having kind of a seperate bundle for every single browser out there, but i think we can at least consider to do different bundles for es6 capable browsers and none es6 capable