Senior Front-End Developer

Segmentify; Greater London; On-site; GBP 90,000 - 120,000; Full time

Job summary

Segmentify is seeking a highly experienced frontend engineer to transform requirements into scalable technical solutions. You will collaborate with product, design, and customer success to deliver reliable deployments used by hundreds of Segmentify customers daily.

The role covers developing across React, Vue, or Svelte, building npm packages, and shaping Front-End CI/CD pipelines. A strong TS background and B2+ years of experience in BFF patterns are valued.

Qualifications

• 7+ years of professional web development experience.
• Deep knowledge of Babel, Vite, and esbuild (plugins, loaders, build optimization).
• Strong experience with npm package development and publishing (monorepo/workspace experience is a plus).
• Proven experience with GitHub Actions for front-end CI/CD.
• Hands-on BFF development experience (Node.js, preferably NestJS/Express).
• Advanced TypeScript knowledge (generics, utility types, strict mode, configuration optimization).
• Experience developing SDKs or client libraries and releasing them to production.
• Experience working on customer integrations and handling revision requests.
• English level B2 or higher – must be comfortable with technical communication, documentation, and client interactions.

Responsibilities

• Develop scalable, maintainable web applications using React, Vue, or Svelte.
• Manage customer integrations, write integration documentation, and support setup phases.
• Analyze and deliver customer revision and feature requests in a timely manner.
• Configure and optimize build pipelines with Babel, Vite, and esbuild (HMR, tree-shaking, code-splitting).
• Develop and publish npm packages with semantic versioning, changelogs, and automated releases.
• Build Front-End CI/CD pipelines with GitHub Actions (lint/test/build/storybook/e2e).
• Design and implement Backend-for-Frontend (BFF) layers with API orchestration, caching, rate limiting, and security best practices.
• Write robust, type-safe code in TypeScript with well-structured domain models.
• Develop SDKs and reusable libraries used by external developers/customers.
• Ensure code quality through unit/integration testing, code reviews, and performance/security improvements.

Skills

TypeScript

React

Vue

Svelte

Babel

Vite

esbuild

npm package development

GitHub Actions

Monorepo / workspace

NestJS / Express (BFF)

Education

BSc or MSc in Computer Science / Software Engineering

Tools

NestJS

Express

pnpm/npm

Storybook

Playwright

Vitest/Jest

Job description

London, United Kingdom | Posted on 17/09/2025

Segmentify is an e-commerce personalization platform helping online retailers to optimise their conversion rates by enabling them to deliver a unique shopping experience for each visitor. Segmentify tracks each individual visitor’s behaviour in real-time and offers smart product recommendations by utilising in-house developed AI technology.

We have a dynamic and passionate compact team dedicated to creating a SaaS solution to boost eCommerce revenue. We are selected as one of the 25 Machine Learning Startups to Watch by Forbes magazine. We are one of the fastest growing start-ups in AI based e-commerce solutions with multiple investment rounds and have offices in 5 countries.

Role:

You will collaborate closely with our product, design, and customer success teams, transforming requirements into scalable technical solutions and ensuring smooth, reliable deployments. Your output shall be used by hundreds of Segmentify customers to configure, run and personalise their campaigns on a daily basis.

Our Tech Stack includes TypeScript, Node.js, React/Vue/Svelte, Vite, esbuild, Babel, pnpm/npm, GitHub Actions, Jest/Vitest, Playwright/Cypress, NestJS/Express, REST/GraphQL (check details from Stack Share Profile )

Responsibilities:

• Develop scalable, maintainable web applications regardless of framework (React, Vue, Svelte, vanilla JS)
  
• Manage customer integrations, write integration documentation, and support setup phases
  
• Analyze and deliver customer revision and feature requests in a timely manner
  
• Configure and optimize build pipelines with Babel, Vite, and esbuild (HMR, tree-shaking, code-splitting, bundle size optimization)
  
• Develop and publish npm packages (semantic versioning, changelogs, automated releases)
  
• Build Front-End CI/CD pipelines with GitHub Actions (lint/test/build/storybook/e2e, caching, multi-environment deployments)
  
• Design and implement Backend-for-Frontend (BFF) layers (preferably using Node.js/NestJS) with API orchestration, caching, rate limiting, and security best practices
  
• Write robust, type-safe code in TypeScript with well-structured domain models
  
• Develop SDKs and reusable libraries used by external developers/customers
  
• Ensure code quality through unit/integration testing, code reviews, and performance/security improvements
  

Requirements

• Develop scalable, maintainable web applications regardless of framework (React, Vue, Svelte, vanilla JS)
  
• BSc or MSc degree in Computer Science, Computer Engineering, Software Engineering or related disciplines from reputable universities
  
• 7+ years of professional web development experience
  
• Deep knowledge of Babel, Vite, and esbuild (plugins, loaders, build optimization)
  
• Strong experience with npm package development and publishing (monorepo/workspace experience is a plus)
  
• Proven experience with GitHub Actions (or similar) for front-end CI/CD
  
• Hands-on BFF development experience (Node.js, preferably NestJS/Express)
  
• Advanced TypeScript knowledge (generics, utility types, strict mode, configuration optimization)
  
• Experience developing SDKs or client libraries and releasing them to production
  
• Experience working on customer integrations and handling revision requests
  
• Strong experience with npm package development and publishing (monorepo/workspace experience is a plus)
  
• Proven experience with GitHub Actions (or similar) for front-end CI/CD
  
• Hands-on BFF development experience (Node.js, preferably NestJS/Express)
  
• Advanced TypeScript knowledge (generics, utility types, strict mode, configuration optimization)
  
• Experience developing SDKs or client libraries and releasing them to production
  
• Experience working on customer integrations and handling revision requests
  
• English level B2 or higher – must be comfortable with technical communication, documentation, and client interactions
  

Nice To Have:

• Monorepo setups (Nx, Turborepo), Storybook, Playwright/Cypress, Vitest/Jest
  
• Performance monitoring (Lighthouse, Web Vitals) and logging/observability
  
• Security best practices (CSP, SRI, OWASP, dependency auditing)
  
• CDN, edge functions, SSR/SSG, ISR architectures
  
• Micro-frontend or design-system experience