Technically, rummy game development requires expertise in programming languages like Java, Kotlin (Android), Swift (iOS) or Javascript depending on the target platform. Developers will also use frameworks and libraries designed for game development, like Unity or Unreal Engine. The game logic will involve complex algorithms for card shuffling, dealing, and hand evaluation to ensure fair and engaging gameplay. Security features to prevent cheating and robust back-end systems for user accounts and transactions are also crucial aspects of rummy game development.