Staff/Principal Software Engineer - Backend

Dex; Greater London; Hybrid; GBP 120,000 - 180,000; Full time

Job summary

Dex is seeking a Backend Architect to define the technical direction for mission-critical systems servicing real-time, AI-powered platforms. You will own backend architecture for distributed services across constrained networks and intermittent connectivity.

The stack is Rust and Python, but the team values language-agnostic approaches. You will write RFCs, mentor engineers, and drive cross-team opportunities while ensuring graceful degradation in demanding operational settings.

Qualifications

• Experience owning architecture for critical systems.
• Proven capability in edge computing or distributed systems.
• Backend experience in Rust/Java/Go/C++ with high reliability.

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.

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.