Blockchain Backend Security Engineer

About the role

ING is building a Digital Asset Services platform to enable secure custody and wallet management for digital assets. As a Blockchain Backend Security Engineer you will design and implement secure backend services, integrate with blockchain SaaS providers, and ensure enterprise‑grade security controls across the platform.

Key responsibilities

• Design, develop and maintain Java‑based microservices that support wallet administration, asset transfers, transaction signing and custody workflows.
• Integrate with blockchain SaaS vendors and institutional custody providers, ensuring high availability and scalability.
• Implement secure key‑management processes, including HSM integration, cryptographic operations and multi‑signature controls.
• Conduct security reviews, threat modelling and apply security‑by‑design principles throughout development.
• Collaborate with DevOps, security engineers and product stakeholders to automate secure deployments and support operational readiness.

Required profile

• Bachelor’s degree in Computer Engineering, Software Engineering or a related discipline.
• Fluent English communication (C1 level or above).
• 5+ years of professional software engineering experience.
• Strong hands‑on experience with Java (Java 17+ preferred) and Spring Boot.
• Experience with RESTful APIs, event‑driven architectures and container technologies (Docker, Kubernetes).

Required skills

• Java (Java 17+), Spring Boot, microservice architecture.
• RESTful API design and event‑driven messaging.
• Docker and Kubernetes container orchestration.
• Multi‑Party Computation (MPC) custody solutions.
• Knowledge of blockchain security, smart‑contract risks and cloud platforms (Azure preferred).
• Familiarity with ISO 27001, SOC2 and Agile/Scrum methodologies.

What we offer

• 14 days of welcome leave in the first year.
• Flexible hybrid working model with remote weeks.
• Self‑driven career opportunities and global mobility.
• Training budget and Udemy partnership for continuous learning.
• Comprehensive health insurance for you and your family.
• Private pension plan, meal card, transportation allowance and MultiSport membership.
• English language development support and an innovation culture powered by PACE methodology.