Worked on the actualbudget/actual repository to enhance authentication security and reliability for API clients using JavaScript and backend development skills. Addressed a critical issue in authentication rate limiting by ensuring only failed login attempts are counted against the quota, which reduces the risk of brute-force attacks and prevents legitimate users from being rate-limited during frequent re-authentication. Implemented the skipSuccessfulRequests parameter in the authRateLimiter, aligning changes with release notes and PR documentation for maintainability. Contributed to both code and documentation, focusing on API development and backend robustness, and improved the overall client experience without introducing new features during the period.