Principle Software Engineer (Java)

Lead architecture, design, and hands-on delivery for a security-critical, multi-tenant fintech platform that issues and manages virtual payment/transit cards across mobile wallets (Apple Wallet, Google Wallet) and EMV/contactless systems — including card tokenization and HSM-backed cryptography. You'll own technical direction across the full lifecycle and raise the engineering bar for payment-grade systems.    Essential Duties and Responsibilities  Own architecture and design for scalability, security, and performance across a schema-per-tenant multi-tenant platform.  Provide hands-on technical leadership end to end, in a domain where financial and cryptographic correctness is paramount.  Build and evolve core subsystems using Java 17/21, Java EE, Spring / Spring Boot: virtual card lifecycle, payment tokenization (e.g., Mastercard MDES), key management, and wallet provisioning (APNs, Google Wallet).  Ensure reliable external integrations — card networks, key-management/HSM services, device notification, and downstream REST/SOAP endpoints — with retries, timeouts, and idempotency.  Design messaging/integration with Kafka and Apache Camel; caching with Redis.  Own data design and performance across PostgreSQL and Oracle (Liquibase migrations, Hibernate/JPA tuning).  Produce design docs, architecture diagrams, and threat models; mentor engineers on coding and secure-coding standards.  Drive CI/CD with Jenkins (pipeline-as-code), Gradle, and Docker.    Required Skills & Qualifications  10+ years in software development with strong Java; 3+ years in technical leadership/architecture.  Bachelor's in Computer Science, Engineering, or related field.  Deep hands-on Java EE, Spring Boot, and Spring on long-lived, service-oriented backends.  Solid security & cryptography: TLS/PKI, key management, HSMs, encryption/signing, secure handling of sensitive data.  PostgreSQL and Oracle (SQL Server a plus) with Hibernate/JPA; multi-tenant data experience strongly preferred.  REST and SOAP integration design with resilient outbound-call patterns.  Containerization (Docker, Kubernetes) and service-oriented/microservices architecture.  Strong grasp of concurrency, transactions, and distributed-system failure modes.  Excellent problem-solving, communication, and leadership.    Preferred Qualifications:  Fintech/payments: EMV, contactless, card tokenization (MDES or equivalent), PCI-aware development.  Mobile wallet provisioning: Apple Wallet (APNs), Google Wallet, or similar device-tokenization flows.  Production Kafka, Camel, Redis; Gradle builds; observability with Micrometer/Prometheus and Log4j2.  Front-end exposure (Angular, Node.js); IaC (Terraform, Ansible) / ARM / CloudFormation.