Senior Java Developer – Security, PKI & Cryptography

Stack

Responsibilities

• ▹Design and development of secure backend solutions in Java
• ▹PKI, certificate management and Certificate Authorities
• ▹Cryptography, TLS/mTLS and secure communication
• ▹OAuth 2.0, OIDC, JWT, JWS/JWE and IAM
• ▹HSM, key management and secure key handling
• ▹APIs, integrations and microservices
• ▹Secure coding, code reviews and threat modeling
• ▹Database security, system hardening and perimeter protection
• ▹Vulnerability management and security in CI/CD
• ▹AI-based tools in development and security work

Requirements

• ▹Several years of Java and backend development experience
• ▹At least 4 years working with several of the following: Java, Spring Boot, Spring Security, REST API, microservices, Maven/Gradle, Git, OAuth 2.0, OIDC, JWT, IAM, PKI, X.509, TLS/mTLS, Bouncy Castle, JCA/JCE, JSSE, certificate management, OCSP/CRL, key management, RSA, ECC, AES, digital signatures and PKCS standards
• ▹Solid experience of Java and the Spring ecosystem
• ▹Experience in security, PKI, cryptography or IAM
• ▹Sees security as a natural part of system development
• ▹Understands integrations, databases, networks and secure communication
• ▹Can take responsibility for technical solutions from idea to production
• ▹Comfortable with architecture and technical choices

Nice to have

• ▹Experience with HSM, Vault/KMS, FIPS, security architecture, Zero Trust, OWASP, penetration testing, CVE/CVSS, Linux security, system hardening, DevSecOps, SAST/DAST, SBOM, software supply chain security, Docker, Kubernetes, AWS/Azure/GCP, Keycloak, post-quantum cryptography or crypto agility
• ▹Experience from safety-critical or regulated sectors such as defence, banking and finance, telecom, public sector or industry

Soft skills

What we offer

• ▹Freedom with responsibility and knowledge sharing
• ▹Regular social activities, shared adventures and an annual trip abroad together
• ▹Technically exciting environments with skilled colleagues and clients

About the company

Sigma is a technology consultancy that is expanding in Blekinge and works on technically complex client assignments with skilled colleagues and clients.