Over a two-month period, contributed to multiple HMRC frontends by modernizing APIs, improving validation, and stabilizing backend processes. In hmrc/pension-scheme-event-reporting-frontend, upgraded the UpscanInitiateConnector to HttpClientV2 and introduced test scaffolding for future coverage, using Scala and Play Framework to enhance maintainability. Addressed input validation in hmrc/pension-administrator-frontend by refining business and partnership name checks, improving data quality and user experience. In hmrc/pensions-scheme-frontend, standardized OptionalSchemeReferenceNumber handling across controllers and services, resolving compilation errors and test failures. Applied skills in API integration, backend and frontend development, and unit testing to deliver maintainable, reliable improvements across these repositories.