Start Small, Grow Big: how to pick the first feature for Event Sourcing

Let’s say we did the hard part. We read up on Event Sourcing, even here on my blog; we did a modelling workshop, we got the nods around the table, and someone finally said:

“Fine, let’s try it somewhere”.

Then, after the cheerful atmosphere, the follow-up arrives:

“OK, but where?”

We do some head-scratching, pick something from the top of our backlog without further consideration. Some people say we should event-source everything so we can select anything, right?

Yes, you can use Event Sourcing everywhere, but you don’t have to, and it won’t add enough value over the familiar approach to justify the learning curve. It’s not that hard; it really doesn’t, but well, if you need to learn both the new approach and new tooling, and persuade colleagues, then it’s better to pick wisely.

In When not to use Event Sourcing? I ended with a suggestion: Start Small, Grow Big. Start with functionality that won’t hurt you if it fails, deploy it to production, learn from it, then rinse and repeat.…