Software Engineer II (Backend, Growth)

At WHOOP, we’re on a mission to unlock human performance and healthspan. WHOOP empowers members to perform at a higher level through a deeper understanding of their bodies and daily lives.

The Growth team is responsible for accelerating member acquisition, activation, engagement, and retention through rapid experimentation and thoughtful product development. As a Software Engineer II (Backend), you’ll contribute directly to building and optimizing backend systems that power WHOOP’s growth initiatives. You’ll deliver high-impact features that directly influence member and business outcomes. You’ll work closely with Product, Design, and fellow engineers in a fast-paced, experiment-driven environment where iteration, measurement, and continuous improvement are core to how we build.

RESPONSIBILITIES:

• Collaborate closely with product managers, designers, and fellow engineers to develop scalable and reliable backend services.

• Build, maintain, and optimize APIs and infrastructure supporting our acquisition funnels, e-commerce experiences, and membership growth experiments.

• Write well-tested, maintainable code using technologies such as Java, Kafka, Postgres, and AWS.

• Break down feature requirements into actionable tasks, prioritize work, and consistently deliver on sprint commitments.

• Contribute to backend architecture discussions and implementation of scalable, high-availability services that support millions of users.

• Work with data scientists and analytics engineers to support experimentation and measure performance.

• Participate in code reviews and collaborate on best practices with your engineering peers.

QUALIFICATIONS:

• Professional backend engineering experience in a production environment.

• Proficiency in building APIs and working with relational databases (e.g., RESTful APIs, Postgres).

• Experience with event-driven systems and asynchronous processing tools such as Kafka or SQS.

• Skilled in writing comprehensive tests and clear documentation.

• Demonstrated ability to work cross-functionally and communicate clearly with technical and non-technical stakeholders.

• A growth mindset and eagerness to learn from feedback and new challenges.

• Bonus: Experience with A/B testing frameworks or growth-focused engineering initiatives.