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Comment by aequitas | Hacker News Reader

I think autodesk did this really well with their Fusion 360 CAD application (probably others as well but this is the one i know).

Because the CAD concept in general is build around parameterisation every modification the user makes needs to be able to be remade with on a different starting (or previous) state. In a way it becomes even more then a first class citizen functionality in the application. The entire history stack (timeline) is available and you can even directly edit, reorder or modify individual steps and their parameters instead of just un/redoing them.

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Is there a name for this kind of architecture? Once I was daydreaming and thought something similar would work well for business CRUD applications. You get an audit log for free, and it would enable offline edits relatively easy.

The principle of immutable log streaming is used in the Lambda[0] and Kappa[1] architectures.

It's also used by state management libraries like Redux[2]. The concept is generic and simple enough that it can be applied to any application where a timeline of state snapshots is useful, so maintaining a history for undo/redo purposes and audit logs is a great fit for it.

[0]: https://en.wikipedia.org/wiki/Lambda_architecture

[1]: http://milinda.pathirage.org/kappa-architecture.com/

[2]: https://redux.js.org/

I'd start looking from "event sourcing".

You will be happy to read this famous post if you haven't yet - log instead of database is a great abstraction! https://engineering.linkedin.com/distributed-systems/log-wha...

In CAD, it's called parametric modeling, at least the part about being able to regenerate from the start. "feature-based" seems to be the aspect of having features attached to other features in a tree structure rather than a linear sequence of operations.

Snapseed (Android & iOS) does a great job as well. It lets you go back to each of the previous steps and edit the parameters without losing your current state.

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