Senior Frontend Engineer - London

Are you a Frontend Software Engineer who thrives on real ownership? At Perk, we know that we feel most fulfilled when we can own the problem and the solution. This means taking responsibility for the entire lifecycle of a feature, from understanding what our customers' pains are with our product team, design documents, coding to deployment, and measuring impact. You will see how your technical decisions move the needle for our customers daily. We prioritize autonomy and pragmatism, giving you the space to solve complex problems without unnecessary friction. Engineering excellence here is measured by the reliability and simplicity of the systems you build to power a global platform.

At Perk, we believe the best work happens when great people come together in small teams, with a shared sense of purpose. You'll join a cross‑functional squad where you have real ownership of a piece of Perk’s domains, a genuine say in what gets built, and the autonomy to make it happen. Each team decides how to contribute to Perk’s company goals. We care about impact, and we trust our people to deliver it. At Perk, we take an IRL‑first approach to work, where our team works together in‑person 3 days a week. As such, this role requires you to be based within commuting distance of our hubs. For certain roles, we can help with relocation from anywhere in the world. English is the official language at the office.

Some examples of what it means to be a Senior at Perk:

• Shape the bigger picture. You won't just build features, you'll refine the what to build and why. At Perk, senior engineers are expected to go beyond the technical solution and focus on the problem itself. You'll contribute to your squad's quarterly goals and long‑term vision alongside your Product Manager and Engineering Manager.
• Architect for today and tomorrow. When a big change is needed in how our platform works, you'll be the one writing the design documents that lay the foundation. You'll become a guardian of your team's technical quality; spotting areas of investment, proactively managing technical debt, and making sure we don't let busy work crowd out the work that truly matters.
• Lead across boundaries. Your influence won't stop at your own squad. You'll communicate complex ideas across multiple teams, proactively identify who needs to be involved, and drive alignment across the broader organisation. Whether it's coordinating a cross‑squad initiative, contributing to one of our engineering guilds, or pairing with architects on solution discovery, you'll operate comfortably beyond your immediate team.
• Raise the bar for everyone around you. Senior engineers at Perk are mentors, coaches, and bar raisers. You'll support less experienced colleagues through direct mentorship, thoughtful feedback during reviews, and by modelling what great engineering looks like in practice. You'll help Engineering Managers understand where the team needs to grow technically, and you'll use spaces like guild meetings, design doc reviews, and pairing sessions to lift the overall standard.

AI is embedded in how we work and what we build. On the engineering side, it spans the whole workflow: our Notion, Jira, GitHub and Slack are AI‑connected so you get up to speed fast, and day‑to‑day it helps with specifying features, writing and reviewing code, and automated AI PR review on every pull request. When something goes wrong in production, AI surfaces context across systems quickly. We also embrace agentic coding, using AI as an active collaborator, not just a prompt‑by‑prompt co‑pilot. We expect candidates to use AI tools in our coding interviews. The bar is understanding your code and owning what you produce. That reflects how we work every day.

What You’ll Bring to the Team:

• Frontend Mastery: Deep technical expertise in the core web stack—JavaScript, TypeScript, CSS, and semantic HTML. You have a profound understanding of the DOM API and a commitment to building accessible, inclusive interfaces.
• Framework Expertise: Proven track record as a Frontend Engineer with deep experience in at least one modern JS framework (React, Vue, Angular, Svelte…).
• Architectural Thinking: The ability to design resilient software systems. You prioritize performance, failure isolation, and long‑term maintainability in every architectural decision.
• AI‑Driven Development: Experience with—or a strong interest in—modern AI‑augmented workflows. This includes leveraging agentic workflows, developing custom agentic skills to extend AI capabilities, utilizing AI‑powered code reviews…
• Mentorship & Leadership: A passion for leveling up the team. You actively invest in the growth of your peers through hands‑on mentorship, code reviews, and knowledge sharing.
• Cross‑Functional Collaboration: A natural bridge‑builder. You can navigate the entire stack, coordinating effectively with other stakeholders, understanding infrastructure and backend services, while translating technical constraints for Product, Data, and Security stakeholders.
• Communication: Exceptional command of English, with the ability to articulate complex technical concepts clearly to both technical and non‑technical audiences.

Bonus Points:

• React Specialist: Deep, production‑level experience specifically within the React ecosystem.
• Domain Expertise: Prior experience navigating the complexities of the Business Travel industry.
• Modular Systems: Familiarity with microfrontend architectures and the challenges of scaling decoupled frontend systems.
• Testing Rigor: A sophisticated understanding of frontend testing strategies (Unit, Integration, E2E) and a drive for industry best practices.

We’re an Equal Opportunity Employer. Perk is a global company with a diverse customer base, and we want to make sure the people behind our product reflect that. We’re an equal opportunity employer, which means you’re welcome at Perk regardless of how you look, where you’re from, or anything else that makes you, well, you.