# Zeal
**Zeal** is a UCI-compliant chess engine written in Rust. I began writing Zeal as a side project while learning Rust. Beating a top engine like Stockfish felt like a long journey, so it seemed fitting to pair that challenge with learning Rust. Zeal is now nearing its first release, though it's still far from its ultimate goal.

## Running and building Zeal
### Play on Lichess
[lichess]() - TODO

### Run locally
```
git clone https://github.com/stefiosif/zeal.git
cargo run -- --mode uci
```

### Run on Cutechess GUI (Windows)
```
git clone https://github.com/stefiosif/zeal.git
cd scripts
./build_windows_bat.sh
```
After building, find the executable in target/x86_64-pc-windows-gnu/release. Use zeal.bat to add Zeal to the Cutechess GUI.

## Core
### Board Representation
- Bitboards
- Redundant Mailbox for piece-square look ups
### Move Generation
- Pseudo-legal move generation
- Magic bitboards for sliding pieces
- Make/Unmake instead of Copy/Make
### Communication Protocol
- UCI
### Search
- Negamax
- Alpha Beta
- Quiescence
- Move ordering (MVV LVA)
### Evaluation
- Material evaluation
- Piece-Square table evaluation

## Next features
- [ ] Iterative deepening
- [ ] Principal Variation
- [ ] Zorbist hashing
- [ ] Transposition tables
- [ ] ...

## Rating
There's no ratings yet for Zeal.

## Acknowledgements
Huge thanks to CodeMonkeyKing and his chess programming videos. His simplistic approach helped me understand the components that constitute a chess engine. Rustic's [roadmap](https://rustic-chess.org/introduction/roadmap.html) guided me in identifying which part of the engine to build next, while the book is an excellent resource for understanding various chess programming concepts. The [Chess Programming Wiki](https://www.chessprogramming.org/Main_Page) provides detailed information about all chess programming topics. Last but not least, I have been reading the code of various chess engines to take ideas, some of them are [bbc](https://github.com/maksimKorzh/bbc), [rustic](https://github.com/mvanthoor/rustic), [tcheran](https://github.com/jgilchrist/tcheran), [purple](https://github.com/JLErvin/purple) and [rush](https://github.com/lefebvreb/rush).

Amazing tools:
- [Bitboard Calculator](https://gekomad.github.io/Cinnamon/BitboardCalculator/)
- [Lichess Editor](https://lichess.org/editor)
- [cutechess](https://github.com/cutechess/cutechess)
- [perftree](https://github.com/agausmann/perftree)

Other resources:
- [The Fascinating Programming of a Chess Engine](https://youtu.be/w4FFX_otR-4?si=_Rt4wcJZsS2duMQM)
- [Coding Adventures: Making a Better Chess Bot](https://youtu.be/_vqlIPDR2TU?si=PKWe_Qu_CPGwIAwE)
- Writing a Chess Engine [Move Generation](https://www.josherv.in/2021/03/19/chess-1/) and [Move Selection](https://www.josherv.in/2022/12/17/chess-2/)