Skip to content

Concepts

  • in Concepts
  • 5 min read

18 Months of Events Fit on Four Floppy Disks

"Event Sourcing uses too much storage." We hear this all the time. The argument goes like this: since you never delete anything and only append new events, your storage requirements grow indefinitely. Eventually, you'll run out of space. It sounds logical. It's also almost always wrong.

The append-only nature of Event Sourcing is real. But the conclusion that this leads to storage problems is based on three fundamental misconceptions that we see over and over again. Let's examine them, and then look at real production data that might surprise you.

  • in Concepts
  • 9 min read

Exactly Once is a Lie

Imagine you're placing an order in an online shop. You click the "Submit Order" button. Nothing happens. You wait a few seconds. Still nothing. So you click again. And maybe once more, just to be sure. Finally, a confirmation page appears. You've successfully placed your order – or have you? Did you place one order, or three?

This scenario plays out millions of times every day across the internet, and it reveals one of the most persistent myths in distributed systems: the promise of exactly-once delivery. Message queues advertise it. Streaming platforms claim it. Enterprise architectures depend on it. But here's the uncomfortable truth: exactly-once delivery is impossible in distributed systems. The good news? That's perfectly okay, and there are practical ways to handle it.

  • in Concepts
  • 12 min read

Proving Without Revealing: Merkle Trees for Event-Sourced Systems

Imagine it's January 2026. You run a platform with millions of users. An auditor walks in with a specific request: "Show me proof that you captured a GDPR consent event for user #12847 on March 15th, 2024." You know the event exists – it's sitting in your event store. But here's the problem: you can't just hand over your complete event log. That log contains millions of events with sensitive customer data, financial transactions, business secrets, and personal information from thousands of other users.

  • in Concepts
  • 9 min read

CQRS Without The Complexity

Imagine you're standing at the counter of your local library. You want to borrow a book – let's say it's "2001: A Space Odyssey". You tell the librarian, they check if the book is available, stamp your card, and hand you the book. Simple, right?