From Wall Street to FinOps: How High-Frequency Trading Math Solved Cloud Cost Allocation

Finout's Co-Founder & CTO explains how the company patented a cloud cost allocation method inspired by high-frequency trading algorithms. The core innovation adapts the ASOF JOIN operation — used in financial markets to match time-series data by proximity — to match cloud billing records against telemetry signals. This reduces computational complexity from O(M×N) to O(M×log(N)), avoiding the expensive Cartesian product approach common in the industry. An additional processing layer handles large 'whale' resource records by splitting them proportionally before matching. The result is dynamically generated Virtual Tag Reallocations that integrate with existing FinOps tooling for budgeting and anomaly detection.