Senior Frontend Engineer (Web & App)
Quantum is seeking a Senior Frontend Engineer to join its Rewards Tech team in Maidstone. This role involves owning the frontend across the Cashback and Custard apps and websites, shipping new functionality that drives revenue, hardening the release pipeline with automated testing, and raising the bar on how the reward products look and feel.
The engineer will work closely with product and backend teams to deliver new app functionality and build and maintain automated end-to-end tests to ensure stable staging environments and predictable releases. The position also requires raising the standard of web and app UX across both reward brands and working full stack where necessary, partnering with backend developers on the Python services behind the apps.
- Own the frontend across the Cashback and Custard apps and websites, from build through to release.
- Ship new app functionality that moves revenue and retention, working closely with product and backend.
- Build and maintain automated end-to-end tests so staging is stable and releases are predictable.
- Raise the standard of web and app UX across both reward brands.
- Work full stack where it counts, partnering with backend developers on the Python services behind the apps.
- Production-grade senior frontend engineering experience with React and TypeScript on the web (required).
- Minimum 6-10 years of experience (required).
- Hands-on experience building and shipping mobile apps, ideally React Native across iOS and Android (required).
- A sharp eye for UX and design, caring about how a product feels (required).
- Comfortable owning end-to-end and staging test automation as part of shipping (required).
- Happy working across the stack, with Python experience being a strong plus rather than a hard requirement (nice-to-have).
- Ability to do best work as part of a team and enjoy sharing knowledge as much as gaining it (required).
- Comfortable navigating a fast-paced environment (required).
- Excellent written and verbal communication skills (required).
- A genuine desire to learn, grow, and lift others around you (required).
- Private Health Care (Bupa)
- Hybrid Working (3 days in office)
- Travel Insurance
- Competitive Base Salary
- Company Bonus Scheme
- Paid for AI Subscription (Claude / ChatGPT / Gemini)
- Market-Leading Training Programme
- Recognition & Reward Scheme
- Annual Company Conference
- Regular Happy Hours & Team Lunches
- Free Coffee, Drinks & Snacks
Quantum is a performance-driven affiliate marketing and digital comparison company that connects global brands with high-intent consumers. Headquartered in London, it builds data-driven comparison services and campaigns designed to be measurable, optimised in real time and scalable. The company combines in-house technology, full-stack analytics and a compliance-first approach to operate in regulated and high-growth sectors. Quantum aims to help users make faster, smarter buying decisions while driving growth for its partners.