Runtime and backend: Java 21 (LTS), Spring Boot 3.5.16, Spring Cloud 2025.0.3, Gradle, Flyway 10.15.
Data: PostgreSQL 17, Redis 7 with Sentinel, RabbitMQ 3.13 with the transactional outbox.
Exchanges: ISO 20022 (pacs.008, pacs.002, camt.056, camt.029); OpenAPI for every service.
Portals: Next.js 16.3.3, React 19, TypeScript 5; Onest typography and two themes; Keycloak 26.1 for OIDC sign-in.
Delivery: Kubernetes and Helm, Vault secrets, Prometheus and Grafana, Docker Compose for pilots.
Evidence by default: every hold, rule change, export and return is journaled for five years.