Senior Embedded Firmware Engineer
Express Employment Professionals - Mequon · Brown Deer, WI
$110,000–$150,000
Jun 29, 2026
Brown Deer, WI
Jul 20, 2026
What this job asks for AI summary
A hands-on firmware role centered on owning embedded software architecture across multiple HVAC product lines — both legacy and new. Day-to-day work spans writing C/C++ firmware for real-time control and communications, supporting bare-metal and RTOS/Linux-based systems, and collaborating with hardware engineers on bring-up and debugging. Suits an experienced embedded developer comfortable in the lab as well as defining system-level architecture and standards.
Senior level · 3+ years · Milwaukee-Waukesha, WI · Bachelor's required · Full-time
Pay in the description: $100,000–$140,000
Advertised as Principal, but the requirements read as Senior.
“or” means any one of them counts — you don't need all of them.
Posted 2 times — it's one opening, so apply once.
We read this from the posting text with AI. Skim the description below before ruling yourself out.
How this req sits in the market our data
Roughly 7 people in the Milwaukee-Waukesha, WI area plausibly meet what this posting asks for (software developers). range 3–15
Applicant volume Light — Few people clear these requirements, so an application that does clear them gets looked at. Worth applying to even if you miss a nice-to-have.
Rare in this occupation — lead with these, and say what you built with them.
What the occupation pays Median $126,451 (middle half $102,189–$141,638). This posting is about at that midpoint.
Estimated from BLS employment for this occupation and area, per-skill prevalence across our listing corpus, and published wage benchmarks — as of Jul 28, 2026. It is a model, not a headcount.
Why we read it this way (6)
The job title in the posting body is 'Principal Embedded Systems Software Engineer' while the header reads 'Senior' — the requirements (3–5+ years, hands-on firmware ownership) align more closely with a Senior-level role than a true Principal, so seniority is assessed as Senior despite the Principal advertised title.
C and C++ are listed together as a single expert-level requirement for embedded systems; they are emitted as separate skills because both are distinct languages used in the stack, but each lists the other as an alternative to reflect the joint framing.
FreeRTOS and Embedded Linux are presented as parallel OS options ('bare-metal and OS-based systems'); FreeRTOS is marked required as the representative of that gate, with Embedded Linux as an alternative. Embedded Linux also appears separately under 'Nice to Have' for deeper/custom Linux distribution experience.
The communication protocols (I2C, SPI, UART, RS-485) are all listed together under the required qualifications section and are each marked as hard gates.
All 'Nice to Have' items (STM32, Embedded Linux custom distro, RTOS scheduling depth, HVAC/industrial domain, BACnet, Qt/QML, SQLite) are marked preferred. HVAC/industrial domain knowledge and RTOS scheduling depth are omitted as skills because they name no specific technology or tool.
No employer sponsorship is available; candidates must already be authorized to work in the US.
Read the full posting
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