Senior Network Administrator - Global Infrastructure

ABOUT SUMUP

SumUp helps businesses get paid effortlessly, process orders fast, sell online instantly, and manage money smarter. We build the tools that let merchants thrive and deliver outstanding customer experiences. But we don’t just simplify transactions - we’re reshaping the future of fintech.

As a global fintech leader, our success relies on more than just code - it depends on a bulletproof, resilient network. While our commercial platform lives in the AWS cloud, our critical infrastructure spans physical data centers (HSMs), global offices, and secure VPNs that keep our teams and merchants connected 24/7.

We are looking for a Senior Network Administrator to join our Sofia-based team. You will be managing network equipment, you will be a co-architect of our global connectivity strategy, ensuring that our infrastructure scales as fast as our business.

What You’ll Do: 

• Manage a complex hybrid environment including cross-region AWS setups, on-premise Juniper/Fortigate/Cisco devices, and global office networks.
• Configure and manage inter-region connectivity using AWS Transit Gateways, VPC peering, and Site-to-Site VPNs.
• Utilize different routing and switching protocols to optimize traffic flow and provide redundancy. 
• Implement zero-trust security guidelines across switches, routers, and firewalls
• Support the co-design of network strategies, focusing on improving site networking and infrastructure resilience.
• Provide 2nd and 3rd level support for network security incidents and maintain high-quality technical documentation.

What we’re looking for:

• Strong experience with routing protocols (BGP, OSPF) and L2 technologies (VLANs, STP, LACP).
• Hands-on experience with AWS networking (VPCs, Subnets, regions) alongside physical hardware from vendors like Fortinet, Juniper, or Cisco Meraki.
• You are a pro with tcpdump, Wireshark, and NetFlow to diagnose complex issues.
• Good Linux administration knowledge and experience with scripting to automate repetitive tasks.
• You understand the "hardware" side, from optical networks (SFP modules) to power budgets.
• You enjoy collaborating across tribes (Infosec, Global IT) and have a service-oriented mindset.

Nice to have: 

• Experience with Kubernetes networking and container principles.
• Familiarity with Terraform (IaC) and Version Control (GitHub).
• Knowledge of Cloudflare services and Zero Trust implementation.

Why you should join SumUp: 

• Collaborate with SumUppers worldwide on large-scale fintech products used by millions, based in our Sofia office (office-first setup).
• Access a €2,000 annual L&D budget to attend conferences or advance your career through education.
• Participate in our VSOP program and own a stake in SumUp’s future success.
• Enjoy 25 days of paid leave (increasing with tenure), plus paid vacations for special occasions and a 1-month sabbatical every 3 years.
• Benefit from extra perks like health and life insurance, co-sponsored Multisport cards, childbirth/adoption bonuses, discounts, a referral program, monthly food vouchers, flexible benefits, and more.

Please note: This role requires the right to work in Bulgaria. We are currently not able to support visa applications or relocation for this position at this time.

 

About SumUp 

We believe in the everyday hero.

Small business owners are at the heart of all we do, so we create powerful, easy-to-use financial solutions to help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that the small business owners we partner with can be successful doing what they love. 

SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, color, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind.

SumUp will not accept unsolicited resumes from any source other than directly from a candidate.