Entities, Components, and Systems: How Bevy Games Work

How do you organize the code for a video game? What happens when hundreds or thousands of objects need to move, interact, and change state?

Join us for Part 2 of our three-part series on game development with Rust and Bevy, where Dominik Stefancik will introduce the Entity Component System (ECS) architecture that forms the foundation of Bevy.
Unlike traditional object-oriented game engines, Bevy organizes game behavior around entities, components, and systems. This provides an interesting opportunity to explore a different approach to software architecture, particularly when working with Rust.

We'll explore:

• ECS fundamentals: What is an Entity Component System, and why do game engines use it?
• ECS versus object-oriented programming: How composition of data and behavior compares with traditional objects and inheritance.
• Entities: How Bevy represents individual objects in a game world.
  - Components: How data is attached to entities to describe their properties and state.
• Systems: How Rust functions operate on entities and components to implement game behavior.
• Practical examples: See these concepts in action using code from real Bevy games.

ECS is more than a game development technique. It offers a different way to think about data, behavior, modularity, and software composition.
We'll see how Bevy uses Rust's type system and query mechanisms to organize game logic. Even if you never develop a game, the architectural concepts are interesting for anyone designing software in Rust.

About the speaker
Dominik Stefancik is a senior software engineer working primarily on backend systems and integrations. He uses Rust for hobby projects, particularly game development, and has created games in Rust, Python, and JavaScript.

You can explore his games and source code here:
GitHub: https://github.com/DominikStefancik/Games

Event details
- Saturday, December 5, 2026
- 11:00 AM EST / 5:00 PM CET
- Online meetup
- Approximately 45 minutes of presentation and code examples, followed by 15 minutes of Q&A and community discussion.

No Bevy or game development experience is required.

This is Part 2 of our series, but you do not need to have attended Part 1. We'll introduce the necessary concepts as we go.