This deliverable is led by Task T4.1, and details the design, development, and deployment of the User Portal within the Genomic Data Infrastructure (GDI), enabling live cataloguing of datasets and secure, standards-based data discovery in a federated ecosystem. Key technical achievements include: Integration with FAIR Data Point (FDP) for metadata-level dataset discovery, aligned with FAIR principles. Adoption of DCAT-AP 3.0 and draft HealthDCAT-AP for health-specific metadata profiles. Implementation of dataset access request workflows via the Resource Entitlement Management System (REMS). Record-level dataset discovery via the Beacon Network for federated genomic queries Development of open-source metadata tooling, including Semantic Models Pydantic RDF Ontology (SemPyRO) and Shapes Constraint Language (SHACL), for onboarding and validation. Enhanced platform operations (CI/CD, OpenTelemetry, vulnerability scanning, license compliance checks). A staging environment has been deployed in collaboration with Work Package 3 (WP3), integrated with the Life Science Authentication and Authorization Infrastructure (LS-AAI) and REMS. The User Portal’s full functionality was successfully demonstrated in Milestones MS7, MS8, and MS11. Despite pending legal establishment of the European Digital Infrastructure Consortium (EDIC), the User Portal is technically ready for being operated in production. Major ongoing development of core interoperability components, like a GDI-specific data model for Beacon queries, and the final version of HealthDCAT-AP, will require further development, but do not pose operational impediments.