What if your app had a Git history?

What if your app had a Git history? | Issue #80

Published about 2 months ago • 1 min read

Hi there,

Most apps only store the final result: the current balance, the current inventory, the current status.

But what if you could track every change that led to that result?

That’s exactly what the event sourcing pattern allows you to do. Instead of overwriting state, you store a sequence of immutable events and derive the current state by replaying them. It’s like Git (kinda), but for your domain logic.

In this week’s video, I show you how to implement event sourcing in Python from scratch:

We start with a simple string-based inventory system
Add caching to avoid replaying events unnecessarily
And build projections like “most collected item” or “where items came from”

I also explain how this pattern compares to blockchain and Git, and when it’s the right (or wrong) tool for your project.

Have a great weekend!

Cheers,

Arjan

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