Pakyow.orgv0.11

Simple State Propagation

Simple State Propagation is how Pakyow propagates state changes from one client to another. It allows us to prioritize user trust while making our code faster to write and easier to maintain.

Let's say you're building a comment system. When a comment is added, users should see it immediately without having to reload the page. The new comment should also show up for other users who are currently looking at the page.

Pakyow handles both cases automatically. It accomplishes this by building up rendering instructions and pushing them through a WebSocket to the originating client and any other client that requires an update.

State changes aren't rendered by any client, including the originator, until the backend has validated and persisted the change. This is an important implementation detail that helps to guarantee consistency and is part of prioritizing user trust.

Requiring the server accept state changes before rendering the change helps to guarantee consistency. Without this guarantee, users have no way to know that what they see is reality. This can come back to bite users if, after refreshing, they see state they didn't see before.

In Pakyow, ultimate truth originates only from the One True Server.

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