What is Kaspa's difficulty adjustment algorithm (DAA)?

Kaspa's difficulty adjustment algorithm (DAA) controls how hard it is to mine a new block by examining a window of recent blocks weighted by accumulated work. The key design choice is that the difficulty window is measured in seconds rather than a fixed block count, so it tracks real-time network conditions instead of a raw block tally. One important consequence is that scaling up the block rate is computationally expensive: if the block rate increases by a factor of R, the complexity of running the DAA grows by R² — once because each block takes more steps to validate, and again because blocks arrive R times faster. This matters because any proposal to raise Kaspa's block rate must find ways to keep the DAA overhead manageable, which is the central problem the current Kaspa Improvement Proposals around this area are trying to solve.