Title: Senior Firmware Engineer, Research
Reports to: Engineering Manager

Location: Hybrid, Onsite 3 days per week
Employment type: Full-Time, Exempt
Pay range: $125,000 - $175,000

Final compensation is based on experience, skills, market benchmarks, and internal equity, with potential adjustments for candidate location.

Applicants must be currently authorized to work in the United States on a full-time basis. Cala will consider sponsoring work visas subject to external immigration counsel assessment based on chances of approval.

AI Disclaimer: Cala does not permit the use of AI during interviews and technical testing so that we can property assess thought process and skillset.

Summary

Cala is seeking a Senior Firmware Engineer, Research to join our R&D team. You will own the firmware that goes into our clinical studies: building it, testing it, documenting it, and supporting it while studies are in the field. You will also build the prototypes that tell us whether a new idea is worth pursuing at all. This is a small team working on early-stage technology. Some weeks you are moving fast on a benchtop prototype to answer a question nobody has answered yet. Other weeks you are developing and testing a build that will be given to real patients. Knowing which mode you are in, and adjusting your rigor accordingly, is a core skill of this role. You will also be the bridge to our commercial development team. When research technology graduates into a product, you are the one who explains how it works, what its limits are, and what the commercial team will need to redesign.

Specific Responsibilities:

• Clinical Study Firmware Ownership: Develop, test, document, and release the firmware used in Cala clinical studies. Own build configuration, versioning, release notes, and known-issue tracking so that study data can always be traced back to exactly what was running on the device. Ensure device logs capture clinical research needs.
• Prototyping New Technology: Build fast, focused prototypes to evaluate new sensing, stimulation, and algorithm concepts. Get to an answer quickly and communicate what the data actually shows.
• Testing & Debug: Write and execute firmware test procedures, build bench test setups, and perform joint hardware/firmware debugging with the EE and systems team.
• Study Support: Support clinical and research staff during study execution. Diagnose field issues, extract and interpret device logs, and turn recurring problems into design fixes.
• Translation to Commercial: Document research firmware clearly enough that the commercial team can pick it up. Participate in design reviews and technical handoffs as concepts move toward productization.
• AI-Accelerated Development: Use AI-assisted development tools as a standard part of how you work in order to execute on innovative ideas that weren’t possible before. We expect you to arrive with opinions about where these tools help, where they do not, and how to use them to think big while keeping quality high.

Desired Skills and Experience

• BS/MS in Computer Science, Computer Engineering, Electrical Engineering, or related field.
• 5+ years developing embedded firmware, including low-power and small-footprint designs.
• Strong C programming skills and proficiency in Python.
• Bare metal firmware development on microcontrollers (ARM preferred)
• Experience with ARM Cortex M0, M3, or M4.
• Experience with BLE, including debugging connection and throughput issues in the real world.
• Experience with sensor signal processing, data logging, or on-device algorithm implementation.
• Comfortable with hardware debugging tools: logic analyzers, oscilloscopes, power supplies, and current measurement.
• Hands-on experience using AI development tools to accelerate firmware work or to ramp quickly on unfamiliar systems, with concrete examples you can walk through.
• Track record of adapting to shifting priorities on a small team, and of picking up whatever work the team needs rather than staying in a narrow lane.
• Genuine interest in building technology that treats patients, and a collaborative working style with engineers, clinicians, and research staff.

Nice to Have

• Experience developing firmware in an ISO 13485 medical device quality system.
• Experience supporting devices used in human clinical studies or other regulated research settings.
• Experience developing simple desktop or mobile app prototypes to visualize or analyze sensor data from connected embedded systems
• RTOS experience with Zephyr, FreeRTOS, Linux, or comparable systems.
• Experience taking a research prototype through to a released product.
• Additional wireless technologies such as LTE or WiFi.