Embedded Firmware Engineer – HUSKY Bus Platform

About Urban Sky: 

Urban Sky is a venture-backed aerospace startup that pioneers utilization of the stratosphere and reimagines the way humans view and analyze the earth. We design, build, operate, and sell stratospheric balloon systems, and the data we collect supports a wide range of applications, from real-time wildfire monitoring to urban mapping. Our technology is also employed by government customers including the Department of Defense (DoD), NASA, and others. Urban Sky sends flight vehicles to the stratosphere on a weekly basis. 

Our team consists of engineers, makers, developers, and doers who believe in the power of human potential when passion meets utility within a small, supportive team. At Urban Sky we strive to create a team culture grounded in candor, inclusion, respect and empowerment. 

We aim to build the next chapter of stratospheric history in Denver and are seeking self-starting, open-minded, and hard-working team members. 

About The Role: 

Urban Sky is seeking an Embedded Firmware Engineer to own the technical development and product evolution of our HUSKY bus platform – the backbone of our stratospheric flight systems. HUSKY provides integrated power distribution, Ethernet-based communications, and onboard compute for our balloon vehicles and customer payloads. This role sits at the intersection of firmware engineering, systems architecture, and product development.

As the product lead for HUSKY, you will work closely with the portfolio manager to drive R&D iteration cycles from architecture through validation and handoff to manufacturing. You will also interface directly with defense customers, supporting integration, network accreditation, and cybersecurity compliance requirements. This is a senior, high-ownership role for an engineer who thrives in a vertically integrated startup where decisions at the firmware layer have direct consequences on flight safety, mission success, and customer outcomes.

Key Responsibilities: 

HUSKY Bus Product Ownership

• Serve as the technical product lead for the HUSKY bus platform, owning the firmware architecture and driving iterative development cycles in collaboration with the portfolio manager
• Define firmware requirements with the portfolio manager, as informed by hardware trade studies, system-level constraints, and customer mission needs
• Lead design reviews, architecture decisions, and trade space analyses for new HUSKY revisions
• Manage the transition of validated designs from R&D into the manufacturing pipeline, ensuring design-for-manufacturability and documentation completeness
• Maintain version-controlled firmware baselines and establish robust release processes and configuration management practices
• Manage and develop firmware configuration tools to enable an automated customer interface

Embedded Firmware Development

• Design, develop, and verify embedded firmware for real-time systems operating in the stratospheric environment, including power management, communication schemas, network architecture, and compute subsystems
• Develop and maintain firmware for low-level hardware interfaces including I2C, SPI, UART, CAN, and Ethernet
• Implement and optimize RTOS-based or bare-metal firmware for microcontrollers and FPGAs as appropriate
• Ensure firmware robustness for operation in extreme stratospheric conditions: low temperatures, low pressure, radiation effects, and power constraints
• Develop and execute firmware-level unit tests, hardware-in-the-loop (HIL) test benches, and integration test procedures

Systems Architecture & Model-Based Development

• Define and document the HUSKY system architecture, including interface control documents (ICDs), data flow diagrams, and power budgets
• Apply model-based systems engineering (MBSE) principles to capture system behavior, manage requirements traceability, and support design verification
• Develop and maintain network topology models covering onboard Ethernet, serial communications, and payload interfaces
• Collaborate with mechanical and electrical engineers to ensure firmware design is tightly coupled with hardware constraints and thermal/power profiles

Electrical Engineering Interface

• Leverage a strong working knowledge of electrical engineering principles to inform firmware design decisions, including signal integrity, power sequencing, and peripheral driver development
• Partner with PCB designers and electrical engineers to review schematics, validate hardware bring-up, and debug hardware-firmware interaction issues
• Participate in hardware trade studies and component selection decisions where firmware implications are significant

Defense Customer & Cybersecurity Support

• Serve as a technical point of contact for defense customers integrating with the HUSKY bus, supporting requirements definition, interface documentation, and integration activities
• Support defense cybersecurity and network accreditation efforts, including Risk Management Framework (RMF) processes, STIGs, and authority-to-operate (ATO) activities
• Implement and maintain security controls for networked operational systems, including secure boot, encrypted communications, and access control
• Interface with government program offices and defense contractors in a professional and technically credible manner

Flight Safety & Reliability

• Design firmware with flight safety as a primary constraint, including watchdog management, fault detection and isolation, graceful degradation, and safe-state behaviors
• Conduct failure mode and effects analysis (FMEA) at the firmware and system level to identify and mitigate risk
• Support field operations and anomaly investigations, providing rapid firmware diagnostics and patching as needed
• Maintain thorough documentation of known failure modes, workarounds, and operational limitations

Field Operations & Communications Exercises

• Support field test flights and customer demonstrations, providing on-site firmware expertise to ensure HUSKY bus systems perform reliably throughout all phases of flight operations
• Lead network integration communication exercises with defense customers, evaluating security boundaries, verifying data flows across the HUSKY bus, and validating that network segmentation and access controls perform as designed under operational conditions
• Document exercise findings, network architecture decisions, and security boundary assessments; communicate results clearly to both internal engineering teams and defense customer stakeholders
• Coordinate with the flight operations team and customer representatives to plan and execute pre-flight network checkout procedures, ensuring all payload communications and security configurations are verified prior to launch

Qualifications: 

• 5+ years of embedded firmware engineering experience, with at least 2 years in a lead or senior individual contributor capacity
• Proficiency in C and C++ for embedded targets; Python scripting for test automation and tooling is a plus
• Strong understanding of network topology, including Ethernet, TCP/IP, UDP, and serial communications protocols
• Demonstrated experience with systems architecture, requirements development, and interface definition
• Working knowledge of electrical engineering fundamentals sufficient to read schematics, debug hardware, and drive hardware-firmware co-design
• Experience with version control (Git), CI/CD pipelines for embedded targets, and configuration management
• Excellent technical communication skills; able to produce clear architecture documents, ICDs, and test reports
• Self-directed and capable of managing multiple concurrent workstreams in a fast-paced environment

Nice-to-Haves/Preferred Skills: 

• Experience with model-based systems engineering (MBSE) tools such as Cameo, MagicDraw, or equivalent
• Background working with defense customers or on DoD programs; familiarity with RMF, CMMC, and ATO processes
• Experience with cybersecurity controls for networked embedded systems, including NIST SP 800-171 or STIG compliance
• Familiarity with aerospace or high-altitude platform avionics, including stratospheric balloon, UAS, or small satellite systems
• Experience with FPGAs (Xilinx/AMD or Intel/Altera) and HDL development (VHDL or Verilog)
• Background in power electronics firmware, including battery management, solar charging, or DC-DC converter control
• Experience bringing hardware-firmware products from R&D through manufacturing transition
• Startup or small-team engineering experience

Requirements: 

• Must be a US Citizen or Permanent Resident
• Must be located near Denver, CO
• Ability to obtain and maintain a security clearance may be required for certain programs 

Benefits: 

• Medical, Vision and Dental 
• Unlimited Vacation Days 
• Parental Leave 
• Cell Phone Bill Stipend 
• Stock Options 

NOTE: Research suggests that women and BIPOC individuals may self-select out of opportunities if they don’t meet 100% of the job requirements. We encourage anyone who believes that they have the skills and the passion necessary to succeed here to apply for this role. 

This position may require the candidate to deal with commodities, software, technology, defense articles, and/or technical data which are subject to the Export Administration Regulations and/or the International Traffic in Arms Regulations. Additional information may be requested so as to determine whether export authorization is required from the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls. If authorization is required, employment will be contingent upon the Company successfully obtaining such authorization from the relevant government agency. 

Urban Sky is an equal opportunity employer, and we value diversity. All employment is decided on the basis of qualifications, merit, and business need.