Senior Network Engineer

Hack The Box is the leading cyber readiness platform for the agentic era, battle-testing and upskilling both humans and AI agents to enhance organizational cyber resilience. Trusted by the Fortune 500, government agencies, and MSSPs, the platform delivers threat-informed learning paths consisting of real-world scenarios in gamified labs and live-fire simulations that build and validate offensive and defensive cyber capabilities. With a loyal community of more than 4 million members and 800+ enterprise customers, Hack The Box empowers teams and intelligent systems alike to strengthen cyber defenses and reduce breach risk effectively. Rapidly growing its international footprint and reach, Hack The Box is headquartered in the UK, with additional offices in the US, Australia, and Greece.

• 5+ years of professional experience in network engineering with a focus on data center networking
• Deep hands-on experience with BGP (eBGP/iBGP), including route policies, communities, and prefix management across multi-site environments
• Proven experience designing and operating EVPN-VXLAN fabrics
• Strong proficiency with JunOS and Juniper switching/routing platforms (QFX, MX series)
• Solid understanding of spine-leaf / IP fabric architectures, VLANs, VRFs, and inter-VLAN routing
• Experience with network automation tools (Ansible, Terraform, Nornir or similar)
• Comfortable with Linux networking fundamentals (iptables/nftables, routing, bonding, VXLANs at the host level)
• Strong troubleshooting skills with ability to diagnose complex, multi-layer issues under pressure
• Excellent written communication for documentation and collaboration in a remote-first environment
• Cyber security-minded is a strong plus

Nice to have:

• Experience with multi-region, multi-continent data center network operations
• Familiarity with Ceph or other distributed storage systems from a network-performance perspective
• Exposure to Kubernetes networking (CNI plugins, service meshes, load balancers)
• JNCIA/JNCIS/JNCIP or equivalent networking certifications
• Understanding of Golang for building internal network tooling or automation
• Experience in cybersecurity-focused or platform-as-a-service companies

• Design and implement spine-leaf network architectures across multiple data center sites in the US, EU, Singapore, and Australia
• Operate and troubleshoot BGP (eBGP/iBGP) peering, route policies, and prefix filtering in a multi-site environment
• Build and maintain EVPN-VXLAN overlay fabrics for scalable Layer 2/Layer 3 connectivity across data centers
• Configure, upgrade, and harden Juniper network equipment (QFX, MX series) running JunOS
• Develop and maintain network automation using Ansible, Terraform or similar infrastructure-as-code tooling
• Establish and improve network monitoring, alerting, and observability using Prometheus, Grafana, SNMP, and streaming telemetry
• Plan and execute network capacity upgrades, site bring-ups, and hardware refresh cycles
• Collaborate with platform and systems engineering teams on network requirements for VMware, Kubernetes, and Ceph storage clusters
• Document network designs, runbooks, and standard operating procedures for a globally distributed team
• Participate in on-call rotation for network-related incidents across all regions

Work location options include fully remote work across Europe or relocation to the Athens Tech Hub with relocation support. For candidates in Greece, hybrid work is expected within 55 km of Athens office; beyond this radius, fully remote arrangements are possible.