Merging static and dynamic data in CUE

[verdverm]

On the most recent community call, @mpvl mentioned ideas related to having both static and dynamic data when evaluating CUE. I would love to hear more, so starting a discussion!

Would there be some way to say "this package" has dynamic value? How does this relate to hermiticity, interacting with the outside world, and cue/flow?

I've been working in React and NextJS, and they have a concept where I can say

• client only
• server only
• you decide (by not saying anything)

and then the compilers figure out if I'm using them correctly, especially under composition and nesting. There seems a similar analogy here for CUE and the outside world, or violating hermiticity, like we are allowed to in cue/flow. Perhaps we can mark CUE packages, values, or fields as such, and then let the CUE user decide what mode they want to run a command in, without having to reach for cue/flow, which has more complexities than most use cases really need.

Also curious how filling in these dynamic values would look.

• What would consuming an API look like? What about auth on that API?
• Consuming a file seems related to @embed(), how are the related and different?
• Does this work across modules, such that I could define consistent values with dynamic filling that others can import?
• Does this allow WASM code to fill values?