Senior Mechanical Engineer

Full-time, In-person | Somerville, MA | 135K - 175K USD a year Humanity wastes or burns $50 billion worth of recyclable materials every year – contributing to 50 trillion microplastic particles in our environment, toxic methane emissions, and millions of tons of greenhouse gases. Recycling is not broken because people do not care; it is broken because the systems that support it have failed to keep up. rStream is changing that. We're building the technology infrastructure that the waste management industry has never had: smart, autonomous tools that reduce operational friction, and create new economic incentives around sustainability. rStream is building systems and processes to make the facilities management more efficient and profitable. We're hiring a Senior Mechanical Engineer to own the rSort platform from prototype to production. Hardware is the backbone of this technology. Our autonomous sorting equipment operates in demanding real-world environments where mechanical precision and integration directly determine how effectively materials are collected and separated for remanufacturing. At rStream, your work won't just be noticed; it will directly make the world cleaner and more efficient. If you're a bold, systems-minded engineer who wants to build hardware that operates in the real world at scale, you'll thrive here. As Senior Mechanical Engineer, you will: Lead hardware development and new invention on a world’s first vision guided, redeployable, autonomous waste processing machine Direct system design work, including functional requirements, detailed design, verification plans, and build-and-test procedures to design the rTrailer from concept to full scale manufacturing Get your hands dirty—designing, building, and testing every subsystem of the rSort platform Oversee manufacturing strategies and incoming inspection plans for components and assemblies Support the field service team with troubleshooting and fixing hardware problems Balance design elegance with execution risk as our company ramps up toward commercialization Work cross-functionally with the hardware, software, and management teams to develop and maintain hardware system features and revision roadmap Lead and mentor junior-level engineers and technicians to help the team grow The successful candidate will have: Required: BS (MS preferred) in Mechanical Engineering or a related field Minimum of 5 years of hands‑on, robotics or hardware experience Expert in CAD design (SolidWorks preferred), FEA, and DFx (Design for cost, test, manufacturing) Experience with manufacturing methods like laser cutting, machining, sheetmetal, 3D printing, and other rapid prototyping Hands‑on experience in automation and the integration of custom and commercial components into complex electro‑mechanical systems Independently execute hardware/software integration testing and first‑pass debugging Demonstrated success launching industrial products to market Known for being a team player and willing to help with all type types of work including handling and sorting trash In‑person at rStream's Headquarters, Greentown Labs, Somerville MA Preferred: Experience with bulk material handling system, waste processing technology and/or industrial equipment design and manufacturing PLC programming and industrial communication protocols (EtherNet/IP, PROFINET, Modbus) Familiarity with computer vision, cameras and image processing Hands‑on experience with embedded system bring‑up, including firmware flashing, log capture, and isolating hardware Familiarity with Python for test scripting and debugging hardware interfaces such as sensors, processors, device communication, and signal timing Prior experience at a startup or innovation team Excellent communication, people, and organizational skills A “Startup Attitude”: quick learner, passionate, nimble, and adaptable- you get creative when the answer is not obvious Why Join rStream? We recognize that there is more to work than the day‑to‑day responsibilities. In addition to a collaborative, high‑performing team environment, we’re pleased to offer competitive compensation rates; flexible work hours; and the opportunity to quickly accelerate your learning and growth. Medical and dental insurance FTO - Flexible Time Off Base salary range for this role: $135,000 – $175,000 , depending on experience. Stock Options- The candidate selected for this role will be recommended for a stock option grant commensurate with the position and the candidate’s qualifications. Affirmative Action/EEO Statement: rStream is an Equal Opportunity Employer and values diversity of thought, access, and experiences. Qualified individuals seeking employment with us are considered without regard to race, color, religion, national origin, age, sex, marital status, physical or mental disability, veteran status, gender identity, sexual orientation, or any other characteristic protected by law. rStream Greentown Labs, Somerville, Massachusetts, United States #J-18808-Ljbffr