Senior Firmware Engineer

Tin Can

Senior Firmware Engineer at Tin Can, responsible for the device firmware ensuring calls work seamlessly. Focusing on innovation in device performance and reliability for kids' communication devices.

Posted 7/24/2026full-timeSeattle • Washington • 🇺🇸 United StatesSenior💰 $180,000 - $200,000 per yearWebsite

Core Competencies

Role fit

Core Competencies

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Demonstrates expertise in firmware development for connected devices, particularly in C/C++ on ESP32, with a strong focus on over-the-air updates, audio processing, and cross-functional collaboration with hardware teams. Possesses a reliability mindset and effective communication skills to ensure team alignment and system understanding.

Highest-signal resume keywords

Firmware DevelopmentOver-The-Air UpdatesAudio ProcessingDebugging Across Software/HardwareCollaboration

ATS Keywords

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Applicant Tracking System Keywords

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Hard Skills

C/C++ ProgrammingFirmware ShippingAudio Processing (I2S)Wi-Fi/BLE DebuggingVersioning and RolloutsEcho CancellationPacket-Loss ConcealmentJitter Buffer ManagementSchematic ReadingLogic Analyzer Usage

Soft Skills

Clear CommunicationCollaborative ApproachReliability Mindset

Tools & Technologies

ESP32ThingsboardBLE/BluFiVoIP (SIP/RTP)PCB Design

Industry Keywords

Connected DevicesFirmwareIoTConsumer HardwareElectrical Engineering

Tech Stack

Tools & technologies

IoTVoIP

About the role

Key responsibilities & impact

Own our device firmware end to end (C/C++ on ESP32) — connectivity, provisioning, call behavior, and on-device audio
Make over-the-air updates safe and boring: phased, reversible rollouts you'd trust across the whole fleet, sensible versioning (which builds reach which devices), monitoring for updates that succeed or fail, and recovery for devices that fall out of the update path
Improve how real calls actually sound, working across the on-device audio path — echo cancellation, jitter buffer, packet-loss concealment, and codecs
Chase down the field issues families feel — devices dropping off Wi-Fi, mesh and dual-band quirks, dropped calls — and drive them to root cause
Instrument the fleet so we can see the kid's-eye experience: is the phone reachable, does the call connect, how does it sound, did it drop
Set firmware direction and coordinate the firmware and hardware work, so device-side knowledge and ownership live with the team
Partner across the hardware line — reviewing specs and supporting board bring-up so firmware and hardware decisions account for each other on current and next-gen devices

Requirements

What you’ll need

5+ years building and shipping firmware for connected devices, ideally in C/C++ on resource-constrained microcontrollers (ESP32/Espressif a big plus)
You've shipped firmware to real devices in the field and owned over-the-air updates — staged rollouts, versioning, and failure recovery — at meaningful scale
Comfortable debugging across the software/hardware boundary: reading schematics, reaching for a scope or logic analyzer, and reasoning about audio (I2S), Wi-Fi/BLE, power, and reset behavior
A reliability mindset — you think in terms of what's reproducible, testable, and reversible, and you instrument things so you know what's really happening in the field
A clear communicator who writes things down, because you want the whole team to understand the systems you build
A collaborative, low-ego approach — everyone here sweeps the floor
Bonus: real-time audio or VoIP experience (SIP/RTP, codecs, AEC, jitter buffer, PLC); an IoT fleet platform like Thingsboard; Wi-Fi provisioning (BLE/BluFi) and mesh-network depth; or taking a consumer hardware product from prototype through the factory
Extra bonus: electrical engineering chops — schematic capture, PCB bring-up, or audio hardware design — that let you flex between firmware and electrical work across our hardware program

Benefits

Comp & perks

Offers Equity
Full benefits package