Senior Java Developer - API Gateway

About the role

ING Hubs Romania, a software development hub serving 24 ING units worldwide, is hiring a Senior Software Engineer on its API Gateway team. The team builds and operates the bank-wide enterprise API Gateway, which routes, authenticates and hosts traffic for customers, employees and third parties across all ING units.

Key responsibilities

• Design, build and maintain gateway components such as configuration controllers, domain circuit breakers and routing services.
• Develop and extend NGINX-based gateway configurations and custom modules for Touchpoint, Integration, Outbound and front-end hosting use cases.
• Automate operations with tooling for resource management, configuration deployment and release train orchestration (production deploys twice per week).
• Ensure reliability of a globally critical service with circuit breakers, canary deployments and DDoS mitigation across data centers.
• Work with platform engineers, SREs, security teams and product teams to onboard domains, troubleshoot issues and set gateway standards.
• Handle P1/P2 incidents, emergency production changes and post-mortems.
• Contribute to the CI/CD pipeline with automated testing and configuration validation.

Required profile

• 5+ years of hands-on software engineering experience, with a track record in distributed systems or platform/infrastructure products.
• Strong proficiency in Java; Go, Python, C and Bash are a plus.
• Good understanding of networking fundamentals (HTTP/HTTPS, TLS/mTLS, DNS, load balancing, firewalls, DMZ).
• Strong debugging and incident response skills, and excellent communication in a cross-functional, globally distributed team.

Required skills

• Containerisation and orchestration (Kubernetes, Docker) and CI/CD pipelines.
• NGINX or comparable API gateway/proxy technology (Envoy, HAProxy, Kong).
• Preferred: API gateway experience at scale, OAuth 2.0/OpenID Connect/JWT/SAML, Grafana/Prometheus/ELK and SRE practices, and high-availability/disaster-recovery patterns.