Senior Mechatronics Engineer

THE COMPANY: Juul Labs's mission is to transition the world’s billion adult smokers away from combustible cigarettes, eliminate their use, and combat underage usage of our products. We have the opportunity to address one of the world’s most intractable challenges through a commitment to exceptional quality, research, design, and innovation. Backed by leading technology investors, we are committed to the same excellence when it comes to hiring great talent. We are a diverse team that is united by this common purpose and we are hiring the world’s best engineers, scientists, designers, product managers, operations experts, and customer service and business professionals. If the opportunity to build your career is compelling, read on for more details. ROLE AND RESPONSIBILITIES: The Internal Tools team builds the infrastructure that Juul’s hardware and firmware programs run on. This includes test automation frameworks, CI pipelines, aerosol science instruments, electromechanical fixtures, and the software that ties it all together. We’re a small team of generalists who own projects from first principles to final handoff and work directly with the engineers who depend on what we build. If you’re equally comfortable writing a Python test harness and assembling a precision fixture, you’ll fit right in. Expectations • Work cross-functionally with Firmware, Product Design, Chemistry, and Regulatory teams to translate program needs into reliable, well-documented tooling. • Design and develop test systems and automation tooling. This includes software frameworks, electromechanical fixtures, and instrumentation. • Contribute to the team’s CI/firmware testing infrastructure by developing modular, maintainable test platform components in close collaboration with the firmware engineering team. • Own projects end-to-end. Capture requirements and drive system architecture through fabrication, software integration, validation, and handoff to stakeholders. • Proactively identify gaps, flag risks early, and propose solutions without waiting to be directed. • Consistently produce clear, thorough documentation that enables peers and stakeholders to self-serve and build on your work. • Actively leverage AI coding assistants and LLMs as a first-order productivity multiplier for code generation, debugging, documentation, data analysis, and design iteration. What Ramp-up Looks Like • Within 90 days: Ramped on active Tier 1 projects and making meaningful independent contributions to at least one deliverable. • Within 6 months: Fully own and deliver at least one project from concept through deployment, with stakeholder sign-off. • Beyond: Consistently supporting and delivering tools and fixtures adopted and relied upon by cross-functional teams. Team Snapshot • Small team, real ownership. You won't just be assigned a slice of someone else's project; you'll own yours from kickoff to deployment, with the trust and visibility that comes with it. • Broad by design. The work spans mechanical design, electronics, embedded systems, instrumentation, and software. You're expected to be useful across all of them. • What you build, people use. Firmware engineers, aerosol scientists, and regulatory teams depend on this team's output. You'll always know exactly who you're building for and why it matters. • AI-first, for real. Between test data, automation pipelines, and embedded tooling, there's no shortage of places to apply it. We're actively building that culture and this hire will help drive it. PERSONAL AND PROFESSIONAL QUALIFICATIONS Required • 7+ years of hands-on experience in mechatronics, hardware/electrical engineering, or a closely related discipline, with demonstrated ability to work effectively across mechanical, electrical, and softw