Senior Backend Engineer - London

The company is at an inflection point. We operate in some of the most complex and high-stakes environments in the world - defence, national security, AI and robotics. The decisions we make now will define not just how fast we grow, but who we become.

You will work closely with the entire team. You will be trusted with judgment calls. You will influence the business. And you will see the impact of your work every day. If you are excited by ownership, pace and purpose - and by building something that genuinely matters - we would love to hear from you.

Founded in 2020, the company is a fast-growing UK deep-tech company developing AI and robotic systems designed to operate in mission-critical environments. Our flagship AVIS (A Very Intelligent System) AI framework fuses multi-modal data - text, imagery, telemetry and sensor feeds - enabling operators to interrogate complex information at speed and make better decisions under pressure. Our STRIDER robotic platform performs autonomous tasks in hazardous environments, protecting people while extending operational reach. Our ambition is simple but demanding: to converge AI and robotics so machines can sense, understand and act in complex, real-world environments. We work with defence and security organisations internationally to help protect nations, infrastructure and lives.

You’ll sit at the core of our product, building the systems that make advanced AI usable in the real world. If you enjoy owning backend services end to end, care deeply about reliability and API quality, and want to work hands-on in a high-impact environment, this role offers both autonomy and real impact.

• Backend Architecture & APIs (Primary Focus)
• Design and evolve scalable backend services in Python using FastAPI for high-availability, high-throughput workloads.
• Build well-versioned RESTful APIs aligned to OpenAPI/Swagger, with strong conventions for consistency, idempotency, and backward compatibility.
• Implement authentication and authorization using OAuth2/OIDC, session management, and fine-grained permissions.
• Design and maintain event-driven architectures and background processing pipelines (e.g. Celery, Redis Streams, Kafka) to enable scalable async workloads, retries, and fault-tolerant integrations.
• Design data models and optimise relational databases (PostgreSQL) for performance, partitioning, and horizontal scale.
• Introduce caching, rate limiting, and queuing to meet performance budgets and latency goals.
• Integrate with AI pipelines and model-serving endpoints, including streaming responses, async inference jobs, and robust error/retry semantics.
• Security & Reliability
• Write secure, well-tested code (unit, integration, end-to-end) and uphold coding standards through code reviews.
• Contribute to logging, metrics, and alerting (Prometheus/Grafana, ELK/OpenSearch) for the services you build.
• Support compliance readiness (ISO 27001, GDPR) through secure-by-default design.
• Cross-Functional & Process
• Collaborate closely with the engineering team, product and leadership to scope, sequence, and deliver outcomes.
• Translate product requirements into technical plans, breaking work into milestones with measurable success criteria.
• Mentor engineers on backend design and API ergonomics.
• Infrastructure Contributions (optional)
• Ship services via Docker containers with clean, minimal builds.
• Contribute to IaC (Terraform/CloudFormation) and CI/CD pipelines (GitHub Actions/Argo CD) alongside the DevOps team.
• Support cloud operations with sensible defaults, cost awareness, and environment promotion across dev/staging/prod.

• SC Clearance or the ability to obtain SC (and later DV).
• 5+ years of professional software engineering experience, with a strong focus on backend development in Python and with event-driven architectures.
• Hands-on experience with Palantir Foundry, including working with Foundry APIs, data pipelines, ontologies, or Foundry-based application development.
• Proven experience designing and operating production REST APIs with OpenAPI/Swagger.
• Deep understanding of relational database design, indexing, performance tuning, and migrations (PostgreSQL).
• Proficiency with containerisation (Docker) and Git-based workflows.
• Experience with API versioning, security, documentation strategies, and automated testing.
• Strong problem-solving skills and the ability to work independently with high ownership.

• High-agency engineer who owns outcomes end to end.
• Pragmatic, research-driven approach with a bias to ship and iterate.
• Clear communicator who can talk to stakeholders of varying technical backgrounds.
• Comfortable defining SLAs, making trade-offs explicit, and operating production systems.

Join the most exciting growth area in the UK: AI and Robotics! Every member of the company team has a major impact on the products and services we provide. Regardless of job title, you will get to make a real difference and learn from colleagues about all areas of our business.

Benefits include:

• Rapid career progression and personal growth
• Flexible working hours
• Opportunity to shape the future of a fast-growing business
• Hybrid working model
• Company pension (NEST) with 4% employer contribution
• Private Healthcare
• 29 days holiday + public holidays

The company is committed to creating an inclusive team experience for all. Regardless of race, gender, religion, sexual orientation, age, disability, or parental status, we believe our work is at its best when everyone feels free to be their authentic self.