UK Remote Job – Backend Engineer, Node.js, TypeScript at Nexoya

Job Title: Backend Engineer
Employer: Nexoya
Job Type: Remote
Location: United Kingdom
Salary/Rate: Not Specified
UK Visa Sponsorship: Not Available

This Backend Engineer role focuses on building scalable backend services, API integrations and AI-powered features for Nexoya’s marketing optimisation platform. It offers end-to-end engineering ownership in an AI-first environment, with remote work available within the European Economic Area (EEA).

Description

• Build and maintain backend services using Node.js and TypeScript.
• Develop GraphQL APIs, advertising platform integrations and data ingestion systems.
• Design and deliver LLM- and agent-powered features, including an in-app AI assistant.
• Own backend features from design through deployment to production.
• Deploy and operate services on Azure cloud using Docker and Kubernetes.
• Build reliable data-processing systems using MySQL and RabbitMQ.
• Maintain clear API schemas, stable contracts and reliable integrations.
• Implement AI evaluation, monitoring, retrieval, tool calling and safety guardrails.
• Improve the agent framework, testing practices, code reviews and technical documentation.
• Participate in architectural decisions and rotating internal support duties.

Responsibilities

• Develop, test, deploy and maintain backend applications and services.
• Design and evolve GraphQL APIs and integrations with advertising platforms.
• Build and maintain data ingestion pipelines and message-driven services.
• Implement AI and agent-based capabilities using structured outputs, retrieval and tool calling.
• Monitor production services and improve reliability, performance and maintainability.
• Conduct code reviews and contribute to engineering standards and documentation.
• Collaborate with colleagues on technical decisions and communicate design trade-offs.
• Participate in internal support rotations and resolve technical issues.

Requirements

• At least three years of backend engineering experience with Node.js and TypeScript.
• Strong API design experience using GraphQL or REST.
• Practical experience with MySQL and message brokers.
• Experience deploying services with Docker, Kubernetes and a major cloud platform; Azure is preferred.
• Strong problem-solving skills and an interest in discussing technical trade-offs in writing.
• Commitment to producing clean, maintainable and well-tested code.
• Fluency in English.
• Desirable: Experience with Google Ads, Meta advertising APIs or marketing attribution.
• Desirable: Production experience with AI, LLMs, agents, Anthropic/OpenAI APIs, MCP or retrieval-augmented generation (RAG).
• Desirable: LLM evaluation, observability, data pipelines or AI coding tools such as Claude Code.
• Additional advantage: German language proficiency.