Test Engineer

About Critical Loop

Critical Loop is shaping the next generation of energy systems by building the integrated edge grid of the future. Specializing in advanced energy management and battery control systems, Critical Loop empowers businesses and communities to seamlessly unite distributed energy resources for faster, more reliable, and affordable grid access. With deep expertise in grid modernization and a passion for creating resilient, responsive energy solutions, Critical Loop drives innovation at the intersection of technology and energy.

Test Engineer - On-site in Long Beach, CA

The Role

We are hiring Test Engineers to build our hardware test capability from the ground up. You will be the owner of our hardware-in-the-loop (HITL) infrastructure, production unit test process, and canary fleet procedures, building and maintaining each as the hardware test pipeline our reliability story is built on.

You will design and build the HITL testbeds, stand up the production unit test process, and own the canary fleet procedures that our hardware reliability story is built on. The test outcomes you produce will feed directly back into the hardware we ship to customers. This is a hands-on, on-site role working alongside the Operations and Product Development teams.

What You'll Do

Design, build, and maintain hardware-in-the-loop (HITL) testbeds for Critical Loop's product line, starting with the CLB5100 and expanding to the CLB5020 and beyond

Develop and operate production unit test processes and procedures, ensuring issues are caught before units reach customer sites

Stand up and own canary fleet usage processes, tooling, and operational standards

Author and maintain test procedures, documentation, and standards as the source of truth for how Critical Loop validates hardware

Analyze test data and translate findings into actionable feedback that improves the hardware we ship

Lead root cause analysis on hardware failures and edge cases surfaced through testing, and stay with the problem until it is solved

Partner with engineering and field ops to align test infrastructure with deployment realities

Build the test engineering function from nothing and do not wait for process or tooling to exist before creating it

Must-Haves

Hands-on experience designing, building, and operating hardware test setups — not only running existing ones

Background in power electronics or high-voltage systems

Demonstrated experience authoring test procedures and the operational standards around them with substantive contributions to the build and methodology

Strong root cause analysis skills, with the ability to drive complex hardware issues to ground in systems you own end to end

Willingness to engage with the software side of testing, including reading code, writing scripts, and committing to git repositories

Bachelor's degree in electrical engineering, mechanical engineering, or a related field, or equivalent practical experience

Comfortable operating as the test engineering function for a product line, setting your own priorities and managing your own work without an existing test organization to lean on

Nice-to-Haves

Direct experience with hardware-in-the-loop (HITL) testbeds and the trade-offs around fidelity, cost, and maintainability

Experience with data acquisition systems, sensors, DAQs, and logging or telemetry forwarding software

Familiarity with Python, git, and Linux

Background spanning both R&D and production environments

Work Authorization We are not able to offer visa sponsorship for this role. Candidates must be authorized to work in the United States without sponsorship now or in the future.

At Critical Loop, we're committed to rewarding and supporting our team. Our benefits package includes equity ownership through stock options, giving you a stake in our success, along with comprehensive health coverage (medical, dental, and vision) through an HRA with a generous allowance. We also provide a retirement savings plan and unlimited paid time off so you can recharge and maintain work-life balance.

Critical Loop is an equal opportunity employer. We're committed to building a diverse team and creating an inclusive workplace where everyone can thrive. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, veteran status, or any other protected characteristic under applicable law.