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Comment by horsawlarway | Hacker News Reader

Yes - that's literally exactly what I talked about.

I can tell you - My app renders immediately in these cases, precisely because I lean heavily on a cache.

I preload basically all the data a user might need at startup (prioritizing the current page) and then optimistically render from cache.

I'm very familiar with these kind of situations (I have developed software designed explicitly to handle offline-only cases, and I'm very familiar with how bad a connection might be in rural Appalachian schools.)

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> I preload basically all the data a user might need at startup

This can be a great strategy when you're dealing with bounded data that's not sensitive, but it's important to recognize that this approach is often inappropriate. A web app may be allowing users to wander around terabytes of data, or it may need to make highly consistent authorization determinations before allowing a user to see specific data, or you may need to keep a highly detailed audit log of who requested what when (e.g., if the app targets healthcare or government users), which aggressive preloading would render useless.

> Still doesn't make an SPA the right fit for everything

It's still worth pointing out.

I would counter that data freshness and authZ concerns make SPAs a poor fit for most things. What you're proposing in this thread is that good SPAs essentially need to hold all data client side and not have to worry about out of band cache invalidation, which seems like a pretty rare set of circumstances.

Awesome, thank you for doing that! I wish more people did. I've had several people tell me that "in a web app you only want to load the data you need, at the time you need it" and I die inside a little.

This works great as long as it is not a first visitor though. For new visitors with a spotty connection this will be a nightmare. Also I assume any new update you release which might need to refresh the cache would also be a problem in this situation. I don't think it's that easy. Not saying that you're not doing it right, just that it is not a trivial thing and almost everyone else won't do this right.

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