Software Engineer - Backend (up to £160k)

Dex; Greater London; On-site; GBP 100,000 - 160,000; Full time

Job summary

Dex is partnering with a leading defence-intelligence software company to recruit a senior backend engineer. You will work on a mission-critical stack, primarily Rust and Python, designed for high-stakes environments with intermittent connectivity and embedded systems.

You’ll tackle complex distributed systems, focusing on robustness and fault tolerance. The role emphasizes rigorous RFCs, code review, and collaboration across teams to unblock colleagues and deliver reliable, real-time insights.

Qualifications

• Backend development experience in a systems language.
• Experience building distributed systems with failure modes.
• Expertise in edge computing or latency optimization.
• Familiarity with REST, GraphQL, gRPC/Protocol Buffers, and Arrow.

Responsibilities

• Design and implement features, algorithms, and infrastructure for a mission-critical backend.
• Engineer for extreme conditions: intermittent connectivity and resource-constrained embedded systems.
• Ensure system robustness through testing and benchmarking.
• Contribute to a Rust and Python-based stack with open-source collaboration opportunities.
• Solve complex distributed systems problems where degradation and failures are expected.

Skills

Rust

Distributed systems

Edge computing

Latency optimization

Platform engineering

REST

GraphQL

gRPC

Protobuf

Arrow

Tools

REST

GraphQL

gRPC/Protobuf

Arrow

Job description

This role is with one of Dex's trusted partner companies. We work closely with their teams to truly understand their culture, goals, and what they're looking for, so we can match you with the right opportunity and give you context about the role before you commit to a process. Dex is an AI recruiter agent that helps you run your job search. Tell Dex your stack, seniority, and what you want to build. We will manage your applications and surface other opportunities that are a fit.

The role

This company builds AI software for real-time defence intelligence. Their systems operate on semi-autonomous platforms, turning raw sensor data into actionable insights. The backend infrastructure faces extreme constraints: intermittent connectivity, embedded compute, low-bandwidth radios, and air-gapped networks where trust is never assumed. They're backed by leading investors and are one of Europe's fastest-growing companies.

You'll join a team where reliability isn't a feature, it's the product. Your code will run in high-stakes environments, directly impacting people in critical situations. This isn't about scaling typical web services; it's about engineering robust, fault-tolerant systems for the most challenging operational contexts. Expect a culture built on rigorous RFCs, code review, and a shared commitment to unblocking colleagues.

The work

• Design and implement features, algorithms, and infrastructure for a mission-critical backend.
• Engineer for extreme conditions: intermittent connectivity, resource-constrained embedded systems, and untrusted networks.
• Ensure system robustness and reliability through comprehensive testing and benchmarking.
• Contribute to a Rust and Python-based stack, with opportunities to learn from prominent open-source contributors.
• Solve complex distributed systems problems where partial degradation and failure modes are the default.

What You Bring

• Strong backend development experience in a systems language (Rust, Java, Go, C++, or similar).
• Proven ability to build and operate complex distributed systems, with a focus on failure modes.
• Deep expertise in at least one area: edge computing, latency optimization, or platform engineering.
• Familiarity with backend interface tools like REST, GraphQL, gRPC/Protocol Buffers, and Arrow.

As part of the recruitment process at Dex, we process your personal data in accordance with our Privacy Notice for Job Applicants. This notice explains how and why your data is collected and used, and how you can contact us if you have any concerns.