Backend Engineer

About the role

We are looking for a senior Backend Engineer to lead the evolution of a global platform for a leading UK media organisation. The role focuses on building and scaling transaction systems that support multi‑currency, cross‑border commerce while expanding into new markets.

Key responsibilities

• Design and implement scalable backend services with a focus on correctness and failure handling.
• Lead the creation of a shared transaction and ledger layer used across multiple business lines.
• Develop RESTful and GraphQL APIs for frontend, mobile and seller platforms.
• Handle complex transaction logic including currency conversion, fees, commissions, reconciliation, refunds and regional tax/compliance requirements.
• Improve performance and scalability of real‑time transaction systems and identify bottlenecks.
• Collaborate with teams using Python, Go, Java, Kotlin, C#, TypeScript/Node.js, Ruby and Rust.

Required profile

• Hands‑on senior engineer with architectural leadership experience in high‑scale, distributed environments.
• Ability to work independently, clarify requirements and make pragmatic design trade‑offs.
• Strong problem‑solving skills without reliance on AI tooling for core tasks.

Required skills

• Elixir and the Phoenix framework
• GraphQL
• PostgreSQL
• Redis
• WebSockets and Phoenix Channels
• Message‑driven architectures and asynchronous processing
• Cloud‑native infrastructure for globally distributed workloads
• API design (RESTful and GraphQL)

What we offer

• Hybrid working arrangement (London office and remote).
• 6‑12 month contract with rates dependent on experience.
• Opportunity to shape a high‑impact platform within a market‑leading media company.