magnet, magnets

Hello fellow people :slight_smile:
I want do do a project where I'll hide inside my wooden pawns some magnets or metal (don't know yet i hope you can help me). And if i place them correctly on chessboard something will happen. For example the magnet lock will be turned off (doesnt matter). I dont know what module will be the best.

Hall-effect switches, or reed switches?

Put tiny rare earth magnets in the pieces and magnetic field sensors (hall sensors or reed switches) under the board.