Network Engineer

MARGO; City Of London; Hybrid; GBP 70,000 - 90,000; Full time

Job summary

A leading investment banking firm is looking for a Senior Network Engineer for a critical infrastructure transformation project. You'll drive network automation and re-architect networks for performance. The ideal candidate has experience in low-latency trading environments and strong knowledge of Arista equipment. This hybrid position requires three days in the London office.

Qualifications

• Proven experience in low-latency, high-availability trading environments.
• Strong hands-on knowledge of Arista network equipment and architecture.
• Proficiency in network automation, especially using Ansible.

Responsibilities

• Drive network automation using tools like Ansible.
• Re-architect the network to improve latency and scalability.
• Act as the bridge between infrastructure and trading/application teams.

Skills

Low-latency trading environment experience

Hands-on knowledge of Arista network equipment

Network automation proficiency

Routing protocols (OSPF, BGP)

Packet-level analysis skills

Tools

Ansible

Job description

We are seeking a Senior Network Engineer to join an exciting infrastructure transformation project within a leading investment banking environment. After years of organic growth, the trading network is now undergoing a major overhaul with fresh investment focused on latency-sensitive electronic trading systems.

This is an opportunity to drive real architectural change, implement automation, and work closely with developers and application teams to redesign the network for performance, scalability, and resilience.

Location: Hybrid, London (3 days per week in office)

Your mission:

You’ll join a tight-knit, agile team with broad responsibilities across the trading and corporate networks. Your focus will be to:

• Drive network automation using tools like Ansible
• Re-architect the network to improve latency and scalability
• Act as the bridge between infrastructure and trading/application teams
• Ensure stable operations and lead troubleshooting in production environments

What you'll bring:

• Proven experience in low-latency, high-availability trading environments
• Strong hands-on knowledge of Arista network equipment and architecture
• Proficiency in network automation, especially using Ansible
• Deep knowledge of routing protocols (OSPF, BGP) and IP transmission (Unicast/Multicast)
• Experience working with market brokers and direct market connectivity
• Strong skills in packet-level analysis and root cause troubleshooting
• Ability to capture business/application needs and translate them into technical solutions
• Previous exposure to firewalls, proxies, load balancers (LTM/Web Gateway)

Nice to have:

• CCIE certification or equivalent experience

Key responsibilities:

• Design, document, and deploy new infrastructure following network-as-code principles
• Own high- and low-level design (HLD/LLD) and support knowledge sharing with global ops teams
• Serve as the senior escalation point for London-based trading network issues
• Collaborate with global peers and vendors to manage implementation and upgrades
• Support and optimise monitoring, capacity planning, and incident response

Recruitment process:

• Intro call with our Talent Acquisition team
• Technical interview
• Final meeting with the engineering and project leads

As an employer, MARGO offers equal employment opportunities regardless of gender, ethnicity, religion, sexual orientation, social status, disability, or age. MARGO is committed to fostering an inclusive work environment that reflects the diversity of its teams, and several actions are taken daily to achieve this!