Staff/Principal Software Engineer - Backend

Dex; Greater London; On-site; GBP 90,000 - 120,000; Full time

Job summary

Dex builds AI software that turns unstructured sensor data into real-time operational intelligence, enabling advanced fleets to localise, navigate and perceive the world. We are seeking a backend architect to shape technical direction across challenging, constrained environments.

You will own architecture for backend systems, drive RFCs, and tackle intermittent connectivity, air-gapped fleets and low-trust networks while raising the engineering bar through mentorship and cross-team collaboration.

Qualifications

• Owned architecture and technical direction for critical systems.
• Deep authority in edge computing, latency, distributed systems at scale.
• Built backend systems in Rust, Java, Go, or C++, making hard reliability trade-offs.
• You mentor, review RFCs, and unblock others to raise the engineering bar.
• You are comfortable with ethical considerations in active debate.

Responsibilities

• Own architecture and technical direction for backend systems that other engineers depend on.
• Define and implement solutions for intermittent connectivity, resource-constrained embedded compute, air-gapped fleets, and low-trust networks.
• Drive technical decisions and RFCs for fleet coherence, software versioning over low-bandwidth radios, and trust boundaries in unsecured environments.
• Ensure graceful degradation and reliability in high-stress, real-time operational settings.
• Actively identify and address cross-team technical opportunities and challenges.

Skills

Architecture ownership

Edge computing

Backend systems

Mentoring & RFCs

Ethical considerations

Tools

Rust

Java

Go

C++

Job description

The role

This company builds AI software that transforms unstructured sensor data into real-time operational intelligence, powering semi-autonomous platforms that localise, navigate, and perceive the world in real time. Backed by leading investors, they've secured significant funding to tackle some of the most challenging real-world problems, with senior leadership bringing deep experience from top-tier AI and platform companies.

This is not a typical backend role. The constraints are genuinely unusual: intermittent connectivity, resource-constrained embedded compute, air-gapped fleets, low-trust networks where TLS is not an option. You won't just execute inside an existing design. You'll set the technical direction across these challenges. There's no playbook for these problems. How do you keep a fleet coherent when parts are unreachable for hours? Version and ship software over low-bandwidth radios? Define trust boundaries on an unsecured network? Ensure graceful degradation when lives depend on it? You'll make those calls, argue them through RFCs, and live with the consequences on platforms in active service. This means a licence to look beyond your own team, acting when you spot a missed opportunity. The stack is Rust and Python, but hiring is language-agnostic.

The work

• Own architecture and technical direction for backend systems that other engineers depend on.
• Define and implement solutions for intermittent connectivity, resource-constrained embedded compute, air-gapped fleets, and low-trust networks.
• Drive technical decisions and RFCs for fleet coherence, software versioning over low-bandwidth radios, and trust boundaries in unsecured environments.
• Ensure graceful degradation and reliability in high-stress, real-time operational settings.
• Actively identify and address cross-team technical opportunities and challenges.

What You Bring

• You operate across teams and business lines, having owned architecture and technical direction for critical systems.
• You bring deep authority in edge computing, latency, distributed systems at scale, or serious platform engineering, with proven systems to show for it.
• You've built backend systems in Rust, Java, Go, or C++, making hard reliability trade-offs in production, not just in design docs.
• You raise the engineering bar: you mentor, review, write RFCs that change minds, and prioritise unblocking others over shipping one more thing yourself.
• You are comfortable working in a domain where ethical considerations are an active, ongoing debate, not a settled question.