Over four months, contributed to Klantinteractie-Servicesysteem/KISS-frontend and Interne-Taak-Afhandeling/ITA by delivering 21 features and resolving 12 bugs, focusing on robust API integration, end-to-end testing, and data quality improvements. Enhanced frontend and backend connectivity using TypeScript, C#, and Vue.js, implementing concurrent multi-identifier case lookups, role-based filtering, and reliable email notification workflows. Upgraded test infrastructure with Playwright and CI/CD pipelines, improved error handling, and streamlined configuration management. Refactored registry and contact request logic for maintainability and scalability, while introducing business-rule-driven data retrieval and validation. These efforts improved deployment safety, reduced manual reconciliation, and accelerated case resolution for end users.