Software Engineer II (Backend, Core)

Whoop; Boston (MA); On-site; USD 120,000 - 180,000; Full time

Job summary

WHOOP is seeking a Software Engineer II to build foundational backend services powering the WHOOP App and member experiences focused on fitness, sleep, strain, recovery, and integrations.

You will collaborate with product, design, data science, and performance science to ship reliable features, improve observability, and scale systems for millions of users in Boston. This role requires strong Java backend skills and a passion for engineering excellence.

Qualifications

• Independently deliver production-quality software while collaborating across engineering, product, and design.
• Strong backend development with Java, RESTful APIs, and relational databases like PostgreSQL.
• Experience with cloud platforms and asynchronous systems such as Kafka or SQS.
• Design, test, and maintain reliable, scalable backend services.
• Understanding of distributed systems, observability, and performance optimization.
• Excellent collaboration and communication with cross-functional partners.
• Growth mindset with willingness to learn, iterate, and improve; enthusiasm for AI tooling with quality engineering.
• Bonus: Experience contributing to mobile apps or shared platform services.

Responsibilities

• Own the design, implementation, and delivery of backend services powering member experiences.
• Translate product requirements into engineering work, identifying risks and dependencies.
• Improve system reliability, performance, and observability through testing and monitoring.
• Contribute to shared engineering foundations via code reviews and documentation.
• Support other engineers through collaboration and knowledge sharing.

Skills

Java

RESTful APIs

Distributed systems

Observability

Collaborative mindset

AI tooling

Growth mindset

Tools

PostgreSQL

Kafka

SQS

AWS

Cloud platforms

Job description

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. Our wearable technology monitors vital physiological metrics to offer personalized insights that enhance fitness, health, sleep, and recovery.

As a Software Engineer II on the Core team, you will build the foundational services that power the WHOOP App and develop features that empower members to optimize performance and longevity. You will play a critical role in building and scaling the foundational systems that power the WHOOP member experience for fitness, sleep, strain, recovery, and integrations. You will partner closely with other engineers, product management, design, data science, and performance science to shape and build the polished member-facing experiences for these features.

Responsibilities

• Own the design, implementation, and delivery of backend services that power member-facing experiences, collaborating with cross-functional partners to deliver scalable, reliable solutions.

• Contribute to technical planning by translating product requirements into actionable engineering work, identifying risks and dependencies, and delivering iteratively.

• Improve system reliability, performance, and observability through testing, monitoring, and continuous refinement.

• Contribute to shared engineering foundations through code reviews, documentation, and technical discussions that improve team effectiveness.

• Support other engineers through collaboration, knowledge sharing, and constructive feedback.

Qualifications

• Demonstrated ability to independently deliver production-quality software while collaborating effectively across engineering, product, and design.

• Strong proficiency with backend development, including Java, RESTful APIs, and relational databases such as Postgres.

• Experience working with cloud platforms and asynchronous systems such as Kafka or SQS.

• Experience designing, testing, and maintaining reliable, scalable backend services.

• Understanding of distributed systems, observability, and performance optimization.

• Strong collaboration and communication skills with cross-functional partners.

• Growth mindset with a desire to learn, iterate, and continuously improve.

• Enthusiasm in leveraging AI tools while maintaining high standards for quality and engineering excellence.

• Bonus: Experience contributing to mobile applications or shared platform services.

Learn more about our Software Org and how to be successful in your engineering career at WHOOP via our Career Framework.

This role is based in the WHOOP office located in Boston, MA. The successful candidate must be prepared to relocate if necessary to work out of the Boston, MA office.

WHOOP is an Equal Opportunity Employer and participates in E-verify to determine employment eligibility. It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.