diff --git a/README.md b/README.md
index 344e480..0d9bace 100644
--- a/README.md
+++ b/README.md
@@ -104,6 +104,7 @@ See also [Friends of Rust](https://www.rust-lang.org/friends.html) (organization
 * **Graphics**
   * [ivanceras/svgbobrus](https://github.com/ivanceras/svgbobrus) — converts ASCII diagrams into SVG graphics [<img src="https://api.travis-ci.org/ivanceras/svgbobrus.svg">](https://travis-ci.org/ivanceras/svgbobrus)
   * [RazrFalcon/svgcleaner](https://github.com/RazrFalcon/svgcleaner) — tidies SVG graphics
+  * [Twinklebear/tray_rust](https://github.com/Twinklebear/tray_rusts) — a ray tracer [<img src="https://api.travis-ci.org/Twinklebear/tray_rust.svg">](https://travis-ci.org/Twinklebear/tray_rust)
 * **Operating systems**, see also [A comparison of operating systems written in Rust](https://github.com/flosse/rust-os-comparison)
   * [redox-os/redox](https://github.com/redox-os/redox) — [<img   src="https://travis-ci.org/redox-os/redox.svg?branch=master">](https://travis-ci.org/redox-os/redox)
   * [thepowersgang/rust_os](https://github.com/thepowersgang/rust_os) — [<img src="https://travis-ci.org/thepowersgang/rust_os.svg?branch=master">](https://travis-ci.org/thepowersgang/rust_os)