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Junior Full Stack Developer

Devonshire HayesUpminster, Essex🇬🇧United KingdomPosted 27 Aug 2026

Quick Overview

Seniority
Junior
Employment type
Full Time
Work mode
Hybrid
Location
Upminster, Essex, United Kingdom
DockerExpressNode.jsSASSSQLSQL ServerCSSGitHTMLJavaScriptPlaywrightRESTReactRedisTesting LibraryTypeScriptViteVitest

Job Description

If you are a Full Stack Developer with 1+ years' experience as a Full Stack Developer, we have an exciting new role we would like to discuss with you.

You'll be working on a new platform that guides consumers through the complete online customer journey, from their first visit through identity verification, e-signature and submission.

As a Junior Full-Stack JavaScript Developer, you'll contribute across a React Front End, Node.js services and Microsoft SQL Server. You'll work on real customer-facing features while developing your skills through practical support, code review and clear engineering standards.

This role would suit an early-career developer with strong JavaScript fundamentals, evidence of practical projects and the curiosity to learn how reliable software is built for a regulated consumer environment.

What you'll do

  • Build and improve customer-journey screens and reusable components in React, using React Router, Vite and Sass/SCSS across multiple branded sites.
  • Contribute to Node.js APIs and Back End-for-Front End services using established patterns in Fastify and Express.
  • Write and update parameterised SQL queries, and support database changes through reviewed migrations.
  • Help integrate third-party services such as identity-verification and lead-management providers behind clear interfaces.
  • Write unit, component and end-to-end tests using tools such as Vitest, Testing Library and Playwright.
  • Investigate defects, use logs and development tools to understand their cause, and deliver well-tested fixes.
  • Follow secure development practices for validation, personal data, audit trails and error handling.
  • Take part in code reviews, document your work and ask questions early when requirements or technical decisions are unclear.

What you'll bring

  • A good foundation in JavaScript, HTML and CSS, demonstrated through professional work, an apprenticeship, a placement, a recognised course or a strong portfolio of personal projects.
  • Some practical experience with React, including components, props, state, hooks and forms.
  • An understanding of how web applications communicate with REST APIs and how Front End and Back End code fit together.
  • Basic SQL knowledge, including selecting, joining, inserting and updating data. Experience with SQL Server is helpful but not essential.
  • An awareness of automated testing and a willingness to learn how to write useful, maintainable tests.
  • A careful approach to problem solving, attention to detail and the confidence to explain what you have tried when asking for help.
  • Clear written and verbal communication, reliability and a genuine interest in developing as a full-stack engineer.

Nice to have

  • Experience with Node.js, Express, Fastify or another Server Side JavaScript framework.
  • Personal or commercial projects using relational databases, Docker or continuous-integration tools.
  • Familiarity with TypeScript, Sass/SCSS, Git, Redis or cloud and hosting platforms.
  • An interest in accessible user interfaces, conversion-focused journeys or multi-brand products.
  • Exposure to regulated industries such as financial services or insurance, or to identity-verification journeys.

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