WIP UCI Chess Engine

Overview

Iris is an UCI chess engine written in c++ that I started in May 2025. The name Iris derives from the flower iris, which symbolizes trust, hope, knowledge, and courage. The name also alludes to Iris, the goddess of the rainbow 🏳️‍🌈.

Strength

Version	Release Date	CCRL 40/15
1.0	2025-06-10	N/A
2.0	2025-07-06	3409

Usage

Iris doesn't come with a graphical user interface (GUI). To play against it, you have to download a chess GUI that supports the Universal Chess Interface (UCI) protocol such as cutechess, en-croissant, etc.

Build

Currently, you can only build Iris with g++ that supports c++ 20.

git clone https://github.com/citrus610/iris
cd iris
make

Thanks

• Members of the MinusKelvin & Engine Programming discord server for helping me, they are very cool ❤️
• MinusKelvin and Analog Hors for generously allowing me into their Openbench instance
• Disservin's chess-library for helping me understand move generation, my move generation code is heavily influenced by theirs
• CPW for its resources
• Bullet as the nnue trainer
• The following engines that I use as references:
  • Ethereal
  • Alexandria
  • Obsidian
  • Reckless