Comment by thomasahle

It actually has quite a few performance tweaks that make traditional engines powerful.

For starters:

- A 12x10 Mailbox board representation.

- Killer move heuristic.

- QSearch.

- Null move pruning.

- Move sorting based on captures and positioning.

- MTD-bi search.

- Mate testing based on king capture.

- Transposition tables.

The Chess Programming Wiki is a great place to learn more about all of these though.