Senior Frontend Engineer - Billing in London

Are you a Software Engineer who thrives on real ownership? At Perk, we believe ownership of a feature from customer pain to final deployment is essential. You will be responsible for the entire lifecycle of a feature—understanding customer needs with product teams, writing design documents, coding, deploying, and measuring impact. Your technical decisions will directly affect customer experience on a global scale.

Join the Billing team. Every day, tens of millions of dollars flow through the systems the Billing team owns. We are building the customer‑facing billing experience—invoice, payment, tax detail pages, etc. As the first dedicated frontend hire, you will own the frontend experience from design handoff to a polished product, set up early architectural decisions, and establish frontend practices as the team grows. In parallel, the team is re‑platforming core billing flows to event‑driven, fault‑tolerant systems, scaling AI‑driven invoice processing, and building a cross‑product tax engine. While you focus on frontend, you will be embedded in a larger technical change, gaining exposure to backend challenges and opportunities to contribute beyond the frontend stack.

How we work: Perk’s small, cross‑functional squads emphasize ownership, autonomy, and clear impact. You will collaborate closely with product designers and PMs, shape squad goals, and drive real-world outcomes. The culture supports teamwork, deliberate alignment across teams, and commitment to engineering excellence.

AI at Perk: AI tools augment almost every part of our workflow—code reviews, feature specification, and day‑to‑day tasks. Candidates are expected to use AI in coding interviews, but the core criteria remain code quality and ownership.

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

• Shape the bigger picture: You will refine the “what to build” and “why” for your squad, aligning quarterly goals with product and engineering management.
• Architect for today and tomorrow: You will write design documents for significant frontend changes, manage technical debt, and ensure the team’s technical quality stays high.
• Lead across boundaries: You will communicate complex ideas across multiple teams, coordinate cross‑squad initiatives, and contribute to shared technical guilds.
• Raise the bar for everyone around you: As a mentor and bar raiser, you will coach peers, provide constructive feedback, and elevate overall engineering standards through pairing, design reviews, and guild meetings.

Desired skills and experience:

• Product Leadership: Translate complex business goals into technical roadmaps and de‑risk ambiguous projects.
• Frontend Architecture: Design scalable, evolvable React applications with strong performance, state‑management, and long‑term maintainability.
• Ownership of Customer‑Facing Experience: Take end‑to‑end responsibility for customer‑facing pages, setting early standards for frontend practice.
• Technical Standards: Establish and enforce engineering quality, including CI/CD, testing strategies (unit, integration, E2E/Cypress), and coding standards.
• Frontend Strategy: Define architecture patterns, state‑management, performance budgets, accessibility, and comprehensive testing.
• Operational Maturity: Lead observability, front‑end performance monitoring, SLO definition, incident response, and blameless post‑mortems.
• Security & Risk: Manage frontend security practices, secrets hygiene, dependency risk, and secure handling of sensitive billing/payment data.
• Mentorship & Influence: Elevate the engineering organization through active mentorship, design reviews, and product roadmap influence.
• Cross‑Functional Impact: Coordinate multi‑team deliverables and resolve technical blockers across the organization.
• AI‑Driven Development: Experience with or strong interest in modern AI‑augmented workflows, including agentic code reviews and custom agentic skills.

Location and diversity: We operate an IRL‑first model with in‑office presence three days a week. Candidates should be within commuting distance of one of our London or Boston hubs. The role is open to all, regardless of background, and we are an equal opportunity employer. Perk is a global company with a diverse customer base, and we want our people to reflect that diversity. We welcome applications from anyone, irrespective of appearance, origin, or any other characteristic.