Core Network Architect - Advisor (Contract) | Senior | Saily

The role

An experienced Core Network Architecture Advisor will provide technical guidance and review architectural decisions for mobile core networks. The role involves advising on build-vs-buy decisions, vendor integrations, and identifying architectural risks.

What you will do

• Review and provide feedback on mobile core network architecture including packet core, roaming, and signaling.
• Help engineers navigate complex telco challenges and troubleshoot architectural problems.
• Advise on build-vs-buy decisions, open-source versus commercial solutions, and infrastructure choices.
• Provide technical expertise for evaluating vendors and integrating with mobile network operators.
• Identify architectural weaknesses, scalability limitations, and reliability concerns.
• Share knowledge of telecommunications standards and emerging technologies.
• Act as a technical sounding board for the engineering team.

Required qualifications

• Strong professional background in mobile core network architecture and engineering.
• Hands-on experience designing, deploying, and operating mobile core networks in production environments.
• Solid understanding of mobile packet core technologies (4G/LTE EPC and 5G Core).
• Practical knowledge of mobile network integrations, signaling, roaming, and connectivity infrastructure.
• Ability to evaluate architectural approaches and provide pragmatic recommendations.
• Comfortable working with engineering teams in a consultative capacity.
• Experience with MVNO, MVNE, or international roaming architectures.
• Knowledge of IMS, VoLTE, VoNR, or other voice and messaging technologies.
• Familiarity with eSIM technologies and remote SIM provisioning.
• Experience with cloud-native telecommunications infrastructure, virtualization, or Kubernetes.

Benefits

• Training, mentorship, and room to grow
• Extra vacation days, sick days, and time off
• Private health insurance in Lithuania and Poland
• Free subscriptions to Calm, Headspace, and Mindletic
• Resilience and mindfulness trainings
• In-house gyms, sport cards, online workouts, and personal guidance
• Company-wide trip abroad
• Gifts for birthdays, weddings, and new family members
• Children's summer camps and flexibility around the schedule
• Team building and company events
• Access to coffee bar, open gyms, kids' room, music room, and massage chairs in Vilnius HQ

Before you apply

• Applications may be processed using automated tools for evaluation purposes.

About the company

Saily provides secure mobile data plans in 200+ countries without roaming charges or plastic SIM cards. The service is built for explorers and powered by NordVPN.