Senior Full-Stack Engineer (Backend specialism)

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 all the team. You will be trusted with judgment calls. You will influence the business. And you will see the impact of your work every day in the work we do.

If you are excited by ownership, pace and purpose - and by building something that genuinely matters -we would love to hear from you., We seeking a Senior Full-Stack Engineer (Backend specialism) to own mission-critical services and user-facing features that power our generative AI products. You will design, build, and operate scalable backend systems and contribute to frontend features as needed, taking features end to end from concept to production with clear SLAs and robust reliability.

You'll partner closely with AI, product, and design to turn advanced AI capabilities into intuitive, reliable, and secure user experiences.

Key Responsibilities

Your responsibilities will include, but not limited to:

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.

Frontend contributions

• Contribute to frontend features using React/Next.js, Tailwind, shadcn/ui, TypeScript as required.
• Work with product and design to take features end-to-end, from API through to UI.
• Help maintain a pragmatic frontend stack with a focus on shipping over perfection, without compromising on security.

Infrastructure contributions

• 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.

Security and 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 and 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, API ergonomics.

Do you have experience in TypeScript?, A collaborative and supportive attitude to work is essential for this role. You will be expected to operate at multiple levels within the company, with a strong focus on delivery and attention to detail. You will be comfortable working alone, supporting team members as well as interacting with clients if required., * SC Clearance or the ability to obtain SC (and later DV).

• Proven experience in professional software engineering, with a strong focus on backend development in Python and with event-driven architectures.
• Proven experience designing and operating production REST APIs with OpenAPI/Swagger.
• Comfortable working in a React/TypeScript codebase.
• Deep understanding of relational database design, indexing, performance tuning, and migrations (PostgreSQL).
• Proficiency with containerisation (Docker) and Git-based workflows.
• Familiarity with AWS core services (EC2, VPC, IAM, S3, ALB/ELB, ECR/ECS).
• Experience with API versioning, security, documentation strategies, and automated testing.
• Strong problem-solving skills and the ability to work independently with high ownership.

Soft skills

• High-agency engineer who owns outcomes end to end.
• Pragmatic, research-driven approach with a bias to ship and iterate.
• Clear communicator who can mentor, influence, and raise the bar for the team.
• Comfortable defining SLAs, making trade-offs explicit, and operating production systems.

Salary: Competitive depending on experience, * Salary: negotiable based on experience and attitudes

• Rapid career progression with meaningful ownership of core systems
• Opportunity to shape the future of a fast-growing, successful, early-stage business
• Flexible working hours
• Hybrid working model
• Company pension (UK Government NEST scheme) with company contributions at 4%
• Private Healthcare
• 29 days holiday in addition to public holidays (Full Time Equivalent)

Oxford Dynamics 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.     If you require alternative methods of application or screening, you must approach the employer directly to request this as Indeed is not responsible for the employer's application process.

Founded in 2020, Oxford Dynamics 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. What you will be doing here/ why this role matters Oxford Dynamics is a small team who rely on a collaborative and positive approach and so the right attitude for this role is equally as important as experience. We are at an important stage and time in our growth, and as a Senior Full-Stack Engineer you will be an essential part of our success., Join the most exciting growth area in the UK: AI and Robotics! Every member of the Oxford Dynamics team has a major impact on the products and services we provide. Regardless of job title, you'll get to make a real difference and learn from colleagues about all areas of our business.