Flax Engine
C# and C++ 3D engine developed in Poland, with full source on GitHub and a quarterly royalty above $250,000
Quick Overview
| Company | CODE FLOOD Wojciech Figat |
|---|---|
| Category | Game Engines |
| Headquarters | Poland, Poland |
| Founded | Not stated |
| EU Presence | Yes - Poland (EU) |
| Data Location | Runs locally |
| Open Source | No |
| GDPR Compliant | Yes |
| Self-Hosting | Runs on your own machine; source on GitHub under the Flax licence |
| Main Features | C#, C++, visual scripting, behavior trees, real-time global illumination (DDGI), GPU lightmap baking, large world precision, networking, nested prefabs, Vulkan |
| Pricing | Free for non-commercial and educational use; 4% royalty on gross revenue above $250,000 per game per calendar quarter |
| Best For | Developers who want a C# engine with source access |
| Replaces | Unity, Unreal Engine |
Detailed Review
Flax lists C# and C++ scripting alongside visual scripting, behaviour trees and an extensible editor. Its feature page highlights real-time global illumination, GPU lightmap baking and 64-bit precision for large worlds.
The privacy policy names CODE FLOOD Wojciech Figat as the developer, and the site footer says it is made in Poland. The entity looks like an individual business rather than a large company.
Licensing
Flax is free for non-commercial and educational use. For commercial products you pay 4% of gross revenue after the first $250,000 per game per calendar quarter, with royalty reports due 45 days after the quarter closes.
Source access
The licensing page says users can use the full source code on GitHub, and that all learning resources and samples are free. An end-user licence agreement must be accepted before use.
Tooling
The feature list covers localisation tools, online services for Steam, Xbox Live and PSN, networking and open-world tools such as terrain and foliage.
Limitations to Consider
Royalties apply above $250,000 per quarter and require notification before release, which adds administrative work. The vendor is a small business operating under the name of its founder, which is a continuity consideration. The community is smaller than Godot.
Who Should Use Flax Engine
C# and C++ developers who want engine source access and are comfortable with a royalty only after a high revenue threshold.
Pros and Cons
Pros
- C# and C++ plus visual scripting
- Full source code on GitHub
- No royalty below $250,000 per quarter
- Console export targets listed
- Real-time global illumination built in
Cons
- 4% royalty above the threshold
- Notification and reporting duties
- Small single-founder vendor
- Smaller community than larger engines
Alternatives to Flax Engine
Other European game engines worth comparing before you decide:
Godot Engine
Netherlands · MIT-licensed 2D and 3D engine run by a Dutch foundation
Defold
Sweden · Lightweight cross-platform engine owned by a Swedish foundation
GDevelop
United Kingdom · No-code game engine with an MIT-licensed core and French team
Construct
United Kingdom · Subscription 2D game maker from Scirra in London
See all European game engines or compare them directly against Unity on our alternatives page.
Frequently Asked Questions
It is free for non-commercial and educational use. Commercial products pay 4% of gross revenue after the first $250,000 per game per calendar quarter.
C# and C++ scripting plus visual scripting.
The footer states it is made in Poland, and the privacy policy names CODE FLOOD Wojciech Figat as the developer.