Senior Software Engineer (frontend, Growth)

Whoop Whoop · Consumer · Boston, MA · Software

Senior Software Engineer on the Growth Team at WHOOP, focusing on web experiences for user acquisition, activation, engagement, and retention. Responsibilities include owning technical direction, leading cross-functional projects, designing and executing A/B tests, driving frontend performance, and mentoring engineers. Requires expertise in TypeScript, React, Next.js, web performance, and integrating with payment systems.

What you'd actually do

  1. Own the architecture and technical direction of WHOOP's web experiences, including our Next.js-based join flow, Cloudflare Workers edge infrastructure, and Stripe-powered checkout
  2. Lead cross-functional projects end-to-end from brainstorm and technical planning through implementation, QA, rollout, and post-launch analysis, partnering closely with Product, Design, and Analytics
  3. Design and execute experiments (A/B tests) with rigor, ensuring proper instrumentation, measurement, and iteration based on impact to North Star metrics
  4. Drive frontend performance, accessibility, and reliability across devices and browsers, establishing standards and monitoring that the team can build on
  5. Write clean, well-tested, production-quality code in TypeScript/React/Next.js and integrate deeply with backend services, payment systems (Stripe), and ecommerce platforms (CommerceTools)

Skills

Required

  • TypeScript
  • React
  • Next.js
  • web performance optimization
  • edge computing
  • responsive design
  • payment systems integration
  • A/B testing
  • observability and monitoring tools

Nice to have

  • Cloudflare Workers
  • Stripe
  • ecommerce platforms
  • CommerceTools
  • feature flag / experimentation infrastructure
  • subscription/membership business models

What the JD emphasized

  • 5+ years of professional experience in frontend software engineering, with deep expertise inTypeScript, React, and modern web frameworks (Next.js strongly preferred)
  • Track record of owning and delivering complex, cross-functional web projects from technical design through production rollout
  • Strong understanding of web performance optimization, edge computing (e.g., Cloudflare Workers), and responsive design at scale
  • Experience integrating frontend applications with payment systems (Stripe preferred), RESTful APIs, and third-party platforms
  • Demonstrated ability to design and run meaningful A/B tests and make data-informed decisions in a growth or product engineering context
  • Experience with observability and monitoring tools (e.g., Datadog, Sentry, Amplitude) to proactively identify and resolve production issues
  • Proven ability to mentor engineers, lead technical discussions, and influence engineering practices across a team