Worked on the spruceid/sprucekit-mobile repository to address a critical issue in credential handling by fixing JWT serialization logic. The solution ensured that JWT payloads are no longer double-encoded and are accurately represented as raw byte arrays, directly improving the reliability and security of credential processing. The approach included adding comprehensive end-to-end tests to validate serialization across multiple credential formats, supporting interoperability with downstream services. This work demonstrated proficiency in Rust, backend development, and test-driven development, and involved effective collaboration during the pull request review and merge process to maintain high standards for code quality and production stability.