Mechanical Engineer II

Cala Systems
Wilmington, MA

About Cala Systems, Inc.

Cala designs and builds intelligent heat pump water heaters that redefine the water heating industry with the goal of delivering zero-emission comfort. Combining advanced hardware, sensors, and patented predictive controls, Cala’s unit learns each home’s unique hot water rhythms to improve comfort, maximize savings, reduce carbon emissions, and coordinate with home solar, batteries, and more. Cala is based at our HQ in Wilmington, MA; we’re venture-backed, founded in 2020, and launched our first product in 2025.


The Role, At-a-Glance

Cala is seeking a Boston-area Mechanical Engineer II to take a leading role in the day-to-day hardware development as we scale from a single-product company into a water heating platform leader. This role is in-person in Wilmington, MA.


What Will I Do?

As a core part of the Cala Engineering team, you will:

● Work within a collaborative crossfunctional team to drive day-to-day hardware development as we work on the next generation of Cala products and features - this includes developing and optimizing hardware design at all levels of complexity, from component to subsystem to integrated architecture

● Get your hands dirty - everything from CAD to building simple breadboard prototypes to testing fully developed pilot units and more

● Leverage engineering best practices to define technical targets, test protocols, and success criteria

● Drive forward key activities including R&D, new product development, manufacturing process development, manufacturing preparation, quality testing, field testing, product certification, and supply chain management

● Conduct testing and analyze the results to make informed design iterations so we can build and test some more until it’s right 


What Qualifications Do I Need?

You have a proven track record in hardware design, including:

● BSc in Mechanical Engineering or a similar technical field with at least 4-6 years of experience in hardware design and a proven track record in a product development environment

● Ability to build and design complex assemblies in CAD, preferably Onshape and Solidworks

● Strong hands-on skills, including the ability to build, test, and debug everything from quick-and-dirty prototypes all the way to pre-production by 3D printing, milling, and turning

● Strong analytical skills - the ability to understand the problem-to-be-solved on a deep level and interpret results on more than just a superficial level

● General knowledge of manufacturing best practices including DFM, part selection, and BOM creation

● High comfort level within a fast-paced environment - you’ll be helping to build from the ground up so it’s important to be flexible and capable of adapting to moving targets

● Self-starting attitude - while Cala is a highly collaborative team environment, we’re looking for candidates who can take take a general direction then run with it and make it their own

● Extra credit if you have experience in any of the following: consumer products, manufacturing, IOT products, electronics and software controls, and/or experience with CFD and FEA, experience with thermal sciences and/or heat pump design


Want to Learn More?

Please email careers@calasystems.com with your resume, portfolio, and brief thoughts on:

● Why are you interested in joining a climate tech company/how does it fit with your goals?

● When the time comes for reference calls, what will your colleagues say about you?

● What’s your proudest professional achievement? Why?

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