The team

The Core Applications team takes pride in providing exceptional support and innovative solutions for a diverse range of essential applications and tools, including our Nimbus component library.
We have a passion for excellence. Our dedicated team is committed to optimising user experiences, streamlining workflows, and enhancing productivity across the board. Whether empowering agents with intuitive interfaces, empowering supervisors with powerful management tools, or enabling seamless access to critical applications via multiple platforms, we strive to deliver with utmost efficiency and customer satisfaction.
Our mission is to shape the future of Five9, where innovation and collaboration go hand in hand as we strive to build a world-class ecosystem of integrated solutions that cater to the ever-evolving needs of our valued users.

Role purpose

This role of a Sr Software Engineer– Frontend in the Core Applications team is to develop, maintain, and advance the component library across Five9. Responsibilities include software design and development, testing and documentation across our React component library. A passion for developing consistent, high-quality, and performant user interfaces is a necessity.

How you contribute

• Build Reusable, Responsive, and WCAG Accessible components for our design system and web applications. Translate Figma designs into component code to align with design specifications.
• Maintain and Organize the Design Token system, bootloader, and codemods in collaboration with other Nimbus developers and the design team.
• Continuously Improve our React component library with the latest in frontend packages, patterns, and best practices.
• Ensure Seamless Deployment by implementing CI/CD unit tests, integration tests, and visual regression tests, publish, and communicate component library enhancements.
• Collaborate closely with our cross-functional teams including the design team, product managers, UI Architects, and other frontend developers to build new components and make improvements to existing components.
• Advocate and Propose standards, best practices, and guidelines, to ensure high-quality scalable and maintainable code.
• Mentor and Support other team members with quality-focused code reviews, strategic planning, and knowledge-sharing approach.

Skills, competencies and qualifications

Required:

• 5+ years of post-internship experience with React and TypeScript.
• Strong proficiency in semantic HTML, CSS (preferably SCSS), and JavaScript.
• Experience with component libraries, design systems, and design tokens.
• Have a keen-eye with attention to detail, and problem-solving skills.
• Strong expertise in Web Content Accessibility Guidelines (WCAG).
• Experience with frontend tooling and migration (preferably Vite and Codemod)
• Experience with testing (e.g. React Testing Library, Enzyme, Cypress, Chromatic).
• Experience working closely with designers using Figma.
• Excellent English communication skills, both verbal and written, with a proactive approach to collaboration.
• Self-motivated, enthusiastic, and ownership-driven, with a strong commitment to delivering solutions.
• Bachelor’s degree (or equivalent) in relevant discipline.

Desirable:

• Experience with Tokens Studio and Style Dictionary for managing Design Tokens
• Experience with Storybook.
• Experience with bundlers (e.g. Rollup),
• Deep understanding of CORS, CDNs, i18n

Benefits:

• Five9 Shares
• Bonus Scheme
• 10% Flexi Benefit
• Meal Allowance
• Medical Insurance
• Life Insurance 
• 25 day Annual Leave + Public Holidays

❗️ Important – On-Site Role in Lisbon❗️
This is an on-site position based in Lisbon. Remote or hybrid arrangements are not available. Candidates must already be in Lisbon or be willing to relocate. Full relocation support will be provided if needed. Here you can check our location: BrainRocket Portugal

⚡ We are looking for an experienced Senior HTML/Markup Developer to join our development team in Lisbon and help build and style high-quality iGaming websites. You will play a key role in crafting visually engaging and responsive interfaces by focusing on markup and CSS styling, turning Figma designs into fully functional, high-performance web experiences.

🎯 Your Mission:
Contribute to the creation and customization of new iGaming brand websites. You will be responsible for translating design specifications into pixel-perfect, responsive layouts while ensuring consistency, performance, and maintainability across multiple platforms. Collaboration with designers, developers, QA, and product teams will be central to your role.

✅ Responsibilities:
• Set up and customize new brand websites based on design specifications
• Implement and style interfaces following Figma layouts and branding guidelines
• Work closely with designers to fine-tune and resolve design nuances
• Customize and style key website components, including login and registration pages, dashboards, game halls, sports pages, and navigation elements
• Update and manage core framework versions across brands
• Ensure code quality through code reviews and release management
• Support live brands, handling styling updates, fixes, and feature rollouts
• Collaborate with cross-functional teams to deliver seamless user experiences
• Introduce creative ideas and contribute to continuous improvements in design implementation and performance

✅ Requirements:
• 5+ years of professional experience as an HTML/Markup Developer
• Excellent knowledge of HTML (Pug) and CSS (SCSS)
• Strong understanding of UI/UX design principles, responsive design, and cross-browser compatibility
• Proven experience building adaptive layouts and maintaining pixel-perfect visual quality across devices
• Solid knowledge of CSS/JS animations, transitions, and motion best practices
• Experience working with Figma / Sketch / Photoshop for translating design systems into production-ready interfaces
• Familiarity with CSS preprocessors (Sass/Less) and version control tools such as Git
• Understanding of web performance optimization and accessibility standards
• Strong collaboration skills with designers, QAs, and developers in multi-brand or large-scale environments
• Attention to detail, with an eye for visual precision and consistency
• Intermediate or higher level of English

✅ Nice to Have:
• Experience with frontend build tools (Gulp, Webpack, etc.)
• Knowledge of template engines (Pug, Handlebars, etc.)
• Experience working with CSS frameworks (Bootstrap, Tailwind, etc.)
• Understanding of HTML email templates
• Familiarity with Canvas API, WebGL, ThreeJS, or GSAP for advanced visual effects
• Basic knowledge of Angular (for integration purposes only)

✅ Recruitment Process:

1. Interview with the Recruiter: An introductory conversation to get to know you better, discuss your background, and align expectations about the role and the company.
2. Technical Assessment (HackerRank): A short coding challenge designed to evaluate your technical skills and problem-solving abilities.
3. Technical Interview: An in-depth discussion about your technical expertise, hands-on experience, and approach to solving real-world problems.
4. Final Interview with the Hiring Team: A conversation with team members and leadership to assess cultural fit, collaboration style, and alignment with the team’s goals.
5. Offer: If everything goes well, we’ll move forward with a formal offer to join our team.

✅ We offer excellent benefits, including but not limited to:
💻 Learning and development opportunities and interesting, challenging tasks.
✈️ Relocation package (tickets, staying in a hotel for up to 2 weeks, and visa relocation support for our employees and their family members).
📚 Opportunity to develop language skills, with partial compensation for the cost of English and Portuguese language classes (for localization purposes).
🎾  Partial compensation for tennis and padel lessons.
🏀 Urban Sport membership benefit (the most diverse sports and wellness offering in Europe, with more than 50+ activities).
🏥 Private medical coverage, including inpatient, outpatient, dental care, annual check-ups, and maternity support.
🏝 Time for proper rest, with 24 non-business days per year and an additional 6 paid sick days.
🚌 Transport compensation - 200 euros net per month.
📈 Competitive remuneration level with annual review.
🤝 Teambuilding activities.

❗️ Important – On-Site Role in Lisbon❗️
This is an on-site position based in Lisbon. Remote or hybrid arrangements are not available. Candidates must already be in Lisbon or be willing to relocate. Full relocation support will be provided if needed. Here you can check our location: BrainRocket Portugal

⚡ We are looking for an experienced Senior HTML/Markup Developer to join our development team in Lisbon and help build and style high-quality iGaming websites. You will play a key role in crafting visually engaging and responsive interfaces by focusing on markup and CSS styling, turning Figma designs into fully functional, high-performance web experiences.

🎯 Your Mission:
Contribute to the creation and customization of new iGaming brand websites. You will be responsible for translating design specifications into pixel-perfect, responsive layouts while ensuring consistency, performance, and maintainability across multiple platforms. Collaboration with designers, developers, QA, and product teams will be central to your role.

✅ Responsibilities:
• Set up and customize new brand websites based on design specifications
• Implement and style interfaces following Figma layouts and branding guidelines
• Work closely with designers to fine-tune and resolve design nuances
• Customize and style key website components, including login and registration pages, dashboards, game halls, sports pages, and navigation elements
• Update and manage core framework versions across brands
• Ensure code quality through code reviews and release management
• Support live brands, handling styling updates, fixes, and feature rollouts
• Collaborate with cross-functional teams to deliver seamless user experiences
• Introduce creative ideas and contribute to continuous improvements in design implementation and performance

✅ Requirements:
• 5+ years of professional experience as an HTML/Markup Developer
• Excellent knowledge of HTML (Pug) and CSS (SCSS)
• Strong understanding of UI/UX design principles, responsive design, and cross-browser compatibility
• Proven experience building adaptive layouts and maintaining pixel-perfect visual quality across devices
• Solid knowledge of CSS/JS animations, transitions, and motion best practices
• Experience working with Figma / Sketch / Photoshop for translating design systems into production-ready interfaces
• Familiarity with CSS preprocessors (Sass/Less) and version control tools such as Git
• Understanding of web performance optimization and accessibility standards
• Strong collaboration skills with designers, QAs, and developers in multi-brand or large-scale environments
• Attention to detail, with an eye for visual precision and consistency
• Intermediate or higher level of English

✅ Nice to Have:
• Experience with frontend build tools (Gulp, Webpack, etc.)
• Knowledge of template engines (Pug, Handlebars, etc.)
• Experience working with CSS frameworks (Bootstrap, Tailwind, etc.)
• Understanding of HTML email templates
• Familiarity with Canvas API, WebGL, ThreeJS, or GSAP for advanced visual effects
• Basic knowledge of Angular (for integration purposes only)

✅ Recruitment Process:

1. Interview with the Recruiter: An introductory conversation to get to know you better, discuss your background, and align expectations about the role and the company.
2. Technical Assessment (HackerRank): A short coding challenge designed to evaluate your technical skills and problem-solving abilities.
3. Technical Interview: An in-depth discussion about your technical expertise, hands-on experience, and approach to solving real-world problems.
4. Final Interview with the Hiring Team: A conversation with team members and leadership to assess cultural fit, collaboration style, and alignment with the team’s goals.
5. Offer: If everything goes well, we’ll move forward with a formal offer to join our team.

✅ We offer excellent benefits, including but not limited to:
💻 Learning and development opportunities and interesting, challenging tasks.
✈️ Relocation package (tickets, staying in a hotel for up to 2 weeks, and visa relocation support for our employees and their family members).
📚 Opportunity to develop language skills, with partial compensation for the cost of English and Portuguese language classes (for localization purposes).
🎾  Partial compensation for tennis and padel lessons.
🏀 Urban Sport membership benefit (the most diverse sports and wellness offering in Europe, with more than 50+ activities).
🏥 Private medical coverage, including inpatient, outpatient, dental care, annual check-ups, and maternity support.
🏝 Time for proper rest, with 24 non-business days per year and an additional 6 paid sick days.
🚌 Transport compensation - 200 euros net per month.
📈 Competitive remuneration level with annual review.
🤝 Teambuilding activities.