Node.js/TypeScript Backend Engineer

We’re a multi‑channel, multi‑brand business serving millions of customers a day, with the UK’s largest loyalty scheme and an ever‑evolving set of digital platforms. All of this equals over 1.2 billion transactions each year, presenting a volume, depth and complexity of data that few can match. We don’t think we’re exaggerating when we say we have one of the most exciting engineering environments in the country. In an inclusive, agile environment, you’ll have the space to be curious, to experiment, and to solve real‑world challenges. And you’ll get to see your work powering applications used by millions of people across the UK.

About the Team

You’ll be part of the Martech engineering domain, an independent and empowered engineering initiative created to address the rapid growth and complexity within the Customer & Data division. Martech brings together key products from Customer Decisioning (focused on customer data) and Customer Loyalty (supporting the Nectar brand), with a mission to build cross‑channel and cross‑brand marketing tools that enable data‑driven, world‑class customer experiences at scale. Within Martech, you will work in the MMH (Multichannel Messaging Hub) team. MMH orchestrates campaign delivery across email, push notifications, and personalised content, supporting all brands within the Sainsbury’s Group. The team consists of 7 engineers, a Product Manager, and an Engineering Manager, working collaboratively in an Agile (SCRUM) environment with a strong focus on communication, shared understanding, and continuous improvement.

About the Role

As a Node.js/TypeScript Engineer, you will design and implement server‑side logic within a microservices architecture, contributing to the delivery of scalable, high‑performance services. You will work closely with cross‑functional stakeholders to define and refine solutions, taking ownership of shaping epics and breaking them down into actionable engineering work. This includes refining technical user stories, explaining requirements to the team, and ensuring alignment across stakeholders. The role involves building and integrating services that support large‑scale, data‑intensive applications, interacting with APIs, event‑driven systems, and external platforms.

More about the Role

• Define technical solutions aligned with MMH team standards and Sainsbury’s engineering principles
• Design, build, test, and deploy services and enhancements
• Ensure compliance with quality standards and successful production deployment
• Refine epics and technical user stories, translating them into clear and structured Jira tickets
• Liaise with stakeholders to clarify requirements and ensure shared understanding
• Communicate technical solutions clearly to engineers and non‑technical stakeholders
• Contribute to microservices‑based architectures supporting large‑scale datasets
• Integrate systems with APIs, event‑driven platforms, and third‑party services

Ways of Working

• Strong communication skills, engaging effectively with technical and non‑technical stakeholders
• Collaborative mindset, working closely with cross‑functional teams
• Comfortable working within SCRUM Agile methodologies and adapting to team practices
• Demonstrates empathy and supports team members to deliver effectively

About You

• Strong understanding of engineering principles and architectural best practices
• Comfortable owning and refining ambiguous problem spaces into structured engineering work
• Able to engage stakeholders, clarify requirements, and translate them into actionable tasks
• Confident explaining technical concepts to a range of audiences
• Passionate about building scalable, high‑quality solutions
• Supports team delivery through collaboration, communication, and shared ownership

Essential Criteria

• Proficiency in JavaScript, TypeScript, and Node.js
• Experience working with microservices architecture
• Experience handling large‑scale datasets (millions of rows)
• Strong knowledge of REST, JSON, and SOAP APIs
• Experience writing unit, integration, and end‑to‑end tests
• Hands‑on experience with CI/CD pipelines (GitHub Actions)
• Experience using Git and GitHub

• Familiarity with Kubernetes
• Experience with AWS Serverless services and S3
• Infrastructure as Code using Terraform

• Experience with Snowflake
• Experience working with Kafka

• Knowledge of tools such as NewRelic or Grafana

Desirable criteria

• Familiarity with Salesforce Marketing Cloud and its APIs
• Familiarity with Coding Agent and AI‑driven development best practices

Location and Working Pattern

London‑based role. Flexible working approach combining remote and in‑office collaboration.

Benefits and Rewards

As well as lots of on‑the‑job training and development opportunities, you’ll get:

• Colleague discount across Sainsbury’s, Argos and Habitat
• 10% side project / personal development time
• Generous holiday allowance, with holiday buying scheme
• Bonus scheme – up to 10% of base salary
• Pension plan
• Access to discounts on gym memberships, restaurants, holidays and more

Work‑life balance is important to us, so we offer flexibility in how, where and when you work, combining remote and collaborative working. We are committed to being a truly inclusive retailer. You’ll be supported, developed, and encouraged to grow your career, with opportunities across teams and the wider business.