How do Power BI developers optimize DAX performance?

Developers optimize DAX by minimizing the use of complex calculations at runtime. They write efficient queries using variables to reduce repeated calculations and filter context evaluations. Techniques like pre-aggregating data, summarizing columns, and using calculated tables improve performance. DAX performance tools like Performance Analyzer are used to identify bottlenecks. Power BI development replace iterative functions with aggregations and use SUMX or AVERAGEX selectively. By adhering to best practices and optimizing their DAX expressions, developers ensure that reports perform efficiently even with complex datasets and calculations.