FEEN (Forsyth—Edwards Enhanced Notation) provides a universal, rule-agnostic format for representing board game positions. This gem implements the FEEN Specification v1.0.0 with a modern Ruby interface featuring immutable position objects and functional programming principles. FEEN extends traditional FEN notation to support multiple game systems (chess, shōgi, xiangqi, makruk), cross-style games, multi-dimensional boards, and captured pieces held in reserve. Built on EPIN (piece notation) and SIN (style notation) foundations, FEEN enables canonical position representation across diverse abstract strategy board games. Perfect for game engines, position analysis tools, and hybrid gaming systems requiring comprehensive board state representation.

QPI (Qualified Piece Identifier) provides a rule-agnostic format for identifying game pieces in abstract strategy board games by combining Style Identifier Notation (SIN) and Piece Identifier Notation (PIN) primitives. This gem implements the QPI Specification v1.0.0 with a modern Ruby interface featuring immutable identifier objects and functional programming principles. QPI enables complete piece identification with all four fundamental attributes (family, type, side, state) while supporting cross-style gaming environments. Perfect for multi-tradition board games, hybrid gaming systems, and game engines requiring comprehensive piece identification across different game styles and traditions.