Senior Back-End Security Developer

18 hours ago


Bucharest, Bucureşti, Romania Sigma Software Full time €60,000 - €120,000 per year
Company Description

We're looking for a Senior Back-end Engineer with a strong background in security to help build a next-generation confidential computing system from the ground up.

You'll design cryptographic infrastructure, develop Back-end services and APIs, and shape the core platform architecture. Working with HSMs, TEEs, and enterprise-grade cryptography, you'll operate at the intersection of Back-end engineering and cybersecurity.

If you're eager to build secure, high-performance systems that redefine data protection, join us to shape the future of confidential computing

CUSTOMER 

Our Сustomer is at the forefront of AI and high-performance computing, building next-generation GPU infrastructure to power advanced AI/ML workloads, data analytics, and research.

Their team has decades of hands-on experience with high-performance distributed systems, ranging from creating early distributed clusters at NASA to scaling infrastructure for global leaders such as Google, Microsoft, CoreWeave, and Yahoo/AOL. They know the challenges developers face because they've experienced them, and they're determined to improve the situation.

PROJECT

Today, they're redefining AI infrastructure by putting control and efficiency back into the hands of developers. With the latest GPUs, exceptional reliability, and transparent, fair pricing, they're making powerful AI more accessible and enjoyable to use.

Their mission is simple yet bold: great AI developers deserve great AI infrastructure. By empowering creators with the necessary tools, they're paving the way for real breakthroughs in artificial intelligence, and they're just getting started.

Job Description
  • Design and build high-performance, secure Back-end services for our vault and key management infrastructure 
  • Develop cryptographic workflows, including key generation, rotation, and secure storage mechanisms
  • Build robust APIs with comprehensive authentication, authorization, and rate limiting
  • Write clean, maintainable, and well-tested code with security as a primary consideration
  • Implement comprehensive audit logging and monitoring for security-critical operations
  • Collaborate with the security team on threat modeling and security reviews
  • Participate in code reviews with a focus on security best practices
  • Create technical documentation for internal systems and API endpoints
  • Integrate with Hardware Security Modules (HSMs) and cloud KMS services
  • Implement secure secret management and rotation mechanisms
  • Build defense-in-depth security controls across all services
  • Conduct security analyses of third-party dependencies
  • Participate in security audits and penetration testing remediation
Qualifications
  • 5+ years of Back-end development experience, building production systems
  • Strong proficiency in Python (FastAPI, Django, or Flask) and/or Go, Rust, C++
  • Solid understanding of cryptographic principles, including symmetric and asymmetric encryption, hashing, key derivation and digital signatures
  • Experience with RESTful API design and development
  • Understanding of authentication and authorization patterns (OAuth 2.0, JWT, and mTLS)
  • Upper-Intermediate level of English

Will be a plus:

  • Experience with Trusted Execution Environments, such as Intel TDX, NVIDIA Confidential Computing, or Secure VMs
  • Experience with Git, CI/CD pipelines, and modern development workflows
Additional Information

PERSONAL PROFILE

  • Ability to adapt and thrive in ambiguous and fast-moving startup environments
  • Strong problem-solving skills and the ability to diagnose complex security workflows
  • Excellent communication skills and the ability to collaborate with DevOps, AI, and cloudengineering teams
  • Detail-oriented mindset to ensure high availability and reliable services


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