Worked on the getsentry/relay repository to enhance the reliability and accuracy of AI billing workflows. Focused on backend development using Rust, the primary contribution involved identifying and resolving a critical bug in the cost calculation logic for AI cache-write tokens. This fix addressed an issue where users could be double-charged, thereby improving the integrity and auditability of billing data. Collaborated cross-functionally to validate the solution and ensure maintainability of the codebase. No new customer-facing features were released during this period, with efforts concentrated on reinforcing the backend infrastructure and ensuring precise AI usage cost calculations within the billing system.