Apexx

Frontend Engineer

Lisbon, Remote. Posted a month ago

The role

You will build and evolve customer-facing surfaces for a payments platform, including JavaScript SDKs, payment components, and web applications. The role involves designing high-performance interfaces and working across the frontend and backend boundary.

What you will do

  • Design, build, and maintain JavaScript/TypeScript SDKs and payment components.
  • Build and evolve merchant- and internal-facing web applications.
  • Translate product and design intent into accessible and intuitive experiences.
  • Work across the frontend/backend boundary and design Backend-for-Frontend services.
  • Use automated testing, performance optimisation, and debugging to build reliable software.
  • Version, document, and publish client libraries.
  • Collaborate with Product, Design, and Engineering to shape solutions and evolve architecture.

Required qualifications

  • Proven track record as a Frontend Engineer building sophisticated, high-performance web applications.
  • Deep knowledge of JavaScript/TypeScript, HTML, CSS, the DOM, and browser APIs.
  • Strong experience with modern frontend frameworks.
  • Experience building performant, data-intensive user interfaces and visualisations.
  • Exceptional attention to detail and visual craftsmanship.
  • Strong understanding of browser and web security fundamentals, including cross-origin behaviour, iframes, CSP, and CORS.
  • Commitment to building accessible experiences to WCAG standards.
  • Strong software-engineering judgement and problem-solving skills.

Nice to have

  • Experience building framework-agnostic SDKs, hosted fields, or checkout components.
  • Experience with Backend-for-Frontend patterns and server-side technologies such as Node.js.
  • Experience in payments, fintech, or e-commerce, particularly with PCI DSS, payment forms, or high-scale transactional environments.
  • React

Benefits

  • Competitive salaries
  • Annual leave alongside local public holidays
  • Work remotely from eligible locations for up to 90 days per year
  • Opportunities to learn, grow, and build a career
  • Local benefits package being developed

About the company

APEXX is a global payment orchestration platform with teams across the UK and India. They provide technology that enables enterprise businesses to connect to the global payment ecosystem through a single integration.