# What game engine was Terraria built with?

> Terraria runs on Re-Logic's own code written in C# on Microsoft's XNA Framework, not on Unity, Unreal or any other commercial engine.

Terraria was built in C# on Microsoft's XNA Framework, a set of libraries for making games on Windows and Xbox 360. Re-Logic wrote its own game code on top of XNA instead of using a ready-made engine like Unity or Unreal, so in practice Terraria runs on a custom engine built with XNA.

## Why XNA and C#

When Andrew "Redigit" Spinks started Terraria in January 2011, XNA was a popular free choice for independent PC developers. It handled graphics, sound and input, and let a small team write gameplay in C# quickly. Terraria launched on PC in May 2011.

## What happened after XNA

Microsoft stopped developing XNA, so later versions of the game moved to compatible open-source reimplementations, such as FNA on macOS and Linux, while keeping the same C# codebase. Console and mobile versions were ported, sometimes by partner studios, using their own technology.

## Why it matters for players

- **Modding:** because the game is written in C#, the community built tModLoader, a free modding tool released on Steam with Re-Logic's support.
- **Performance:** the tile-based 2D world is handled by Terraria's own code, which is why large worlds and many entities can still slow older PCs.

## FAQ

**What programming language is Terraria written in?**
C#. Mods made with tModLoader are also written in C#.

**Who developed Terraria?**
Re-Logic, the independent studio founded by Andrew "Redigit" Spinks. Some console and mobile versions were ported by partner studios.

**When was Terraria made?**
Development started in January 2011, and the game launched on PC in May 2011. Re-Logic kept adding major free updates for more than a decade.

**Is Terraria made in Scratch?**
No. Terraria is a commercial game written in C#; fan remakes in Scratch exist but are not the real game.

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https://gamevoyages.com/what-game-engine-was-terraria-built-with/ · Game Voyage · Checked 2026-10-31