During April 2025, Thomas Jackson focused on backend development and API security within the letsencrypt/boulder repository, addressing a nuanced issue in JWS processing. He implemented RFC8555-compliant error handling by introducing explicit BadSignatureAlgorithm error reporting for unsupported JWS signature algorithms, replacing generic parsing failures. This approach improved error classification and reduced noise during parsing, aligning the system more closely with protocol standards. Thomas also developed validation tests to ensure the new error handling worked as intended. His work, primarily in Go, demonstrated depth in error handling and protocol compliance, contributing to more robust and maintainable backend infrastructure for the project.