Full Stack JavaScript Engineer

Zellis

  • Watford, Hertfordshire
  • Permanent
  • Full-time
  • 2 months ago
About the roleWe have an exciting opportunity for a Full-Stack JavaScript Engineer to join the elementsuite team—someone who’s passionate about building high-quality products and tools across the stack. This role blends front-end finesse with back-end capability, and we’re especially keen to meet developers who can pair modern JavaScript frameworks with solid SQL experience to help power our next-gen HR platform.You’ll work closely with our Application Development team to deliver scalable, maintainable software that supports our growing user base. This is a hands-on, end-to-end role—from building intuitive interfaces using Vue.js and Knockout.js, to writing performant queries and helping shape our data model.elementsuite is rewriting the rulebook on how enterprise software is built. Our cloud-native platform powers flexible, scalable, and beautifully simple HR and workforce management solutions. This year, we joined forces with Zellis to create an AI-enabled, end-to-end HR, WFM, and Pay solution. Together, we support some of the biggest brands in the UK & Ireland, combining deep HR domain expertise with next-generation technology to reimagine the world of work: intuitive, connected, and AI-enabled.Key responsibilities in the role will include:Building innovative, high-quality features in line with the elementsuite roadmap. * Writing clean, reusable JavaScript code using modern frameworks (Vue.js, Knockout.js).
  • Creating responsive, user-focused UI/UX with HTML5, CSS3, and SASS.
  • Designing and writing performant SQL queries to support data-driven functionality.
  • Collaborating with other developers and designers to architect robust front-end and back-end solutions.
  • Testing your code with appropriate unit and integration tests.
  • Estimating and managing your workload with a focus on quality and efficiency.
  • Refactoring and improving existing code to maintain performance and scalability.
  • Participating in peer code reviews, offering constructive feedback, and learning from others.
  • Supporting operational sessions with technical insight and analysis.
  • Staying mindful of performance across both client and server-side code.
Skills & experience
  • Proven experience in a full-stack or JavaScript-focused software engineering role.
  • Strong JavaScript skills and experience with modern frameworks (Vue.js, Knockout.js, jQuery).
  • Solid working knowledge of SQL, relational databases, and writing efficient queries.
  • Good understanding of API integration and data flow between front-end and back-end.
  • Familiarity with data visualisation libraries such as D3.js.
  • Strong grasp of MVVM architecture, responsive design, and UI/UX principles.
  • Experience with version control tools like Git or SVN.
  • A pragmatic mindset—able to balance time, cost, and quality while delivering value to users.
Benefits & cultureAt Zellis we create AI-enabled HR, workforce management and payroll products and services, to power exceptional employee experiences so that you and your people do better. Our multi-award-winning products pay over five million employees a year, with almost half (42%) of the FTSE 100, 50% of the top retailers and 30% of the top universities in the UK & Ireland as customers, making us the largest provider of Payroll and HR software and managed services.Our vision is to be the clear leader in pay, reward, analytics, and people experiences. We're passionate about creating an environment where people want to join, belong to, and be part of a progressive organisation. Our values, which were defined with input from all of our 3,000 colleagues, we live and breathe every day:
  • Unstoppable together.
  • Always learning.
  • Make it count.
  • Think scale.
Our people are critical to our ongoing success; we’re proud of our inclusive culture that gives you the platform to grow, challenge the status quo and play a crucial role in further enhancing our market position as the leading provider of HR & Payroll software and services. With Zellis you’ll have the chance to stretch and challenge yourself in an environment that’s varied, flexible and hugely supportive.We also love to reward and recognise our brilliant colleagues. As part of your benefits package, you’ll receive:
  • A competitive base salary.
  • 25 days annual leave, plus your birthday off and the opportunity to buy additional holiday.
  • Private medical insurance.
  • Life assurance 4x salary.
  • Enhanced pension scheme with company contributions up to 8.5%.
  • A huge range of additional flexible benefits across financial & personal wellbeing, lifestyle & leisure.

Zellis