Staff Platform Firmware Engineer

【About Positive Grid】

Positive Grid builds smart guitar technology — the Spark amplifier family and BIAS FX software — sold in over 100 countries. We reached $55M revenue in 2025 while staying profitable, and are targeting $100M by 2028.

【The Role】

Every product we ship is built the same way: a main MCU, a connectivity SoC, and a shared communication protocol. That shared foundation exists in the architecture — but until now, no single engineer has owned it. Each product line has re-implemented connectivity, OTA and protocol handling on its own.

This role changes that. You will be the owner of our cross-product firmware platform: the connectivity stack, the update toolchain, the protocol registry, and the portable layer that lets each new chip platform start from something rather than from zero. You are not maintaining an existing architecture — you are the person who defines where it goes. One engineer, holding the foundation, so that every product line moves faster.

【What You Will Own】

• Own the connectivity platform shared by all connected products — the BLE/WiFi core on ESP32, evolving to the Airoha Bluetooth audio SoC — and the USB firmware-update toolchain. Serve as the platform's dedicated owner and the bring-up lead for new chip platforms.
• Design the portable cross-platform shared layer — connectivity, OTA, protocol and system-service abstractions — spanning the STM32 and Airoha families, so that introducing a new platform no longer costs a full foundation rebuild.
• Govern cross-product communication protocols: own the opcode master registry, manage versioning across product-line branches, and keep the shared numbering space coherent.
• Lead system optimisation across existing codebases: audit and prioritise memory allocation, DMA planning and core resource configuration, and drive convergence of what is currently solved separately in each product.
• Plan a 6–12 month technology roadmap for next-generation firmware platforms, focused on multi-product and feature integration
• Conduct system-level research and evaluation of new chip platforms, aligned with the product strategy
• Provide technical leadership in firmware development, guiding the team through complex, cross-product work
• Collaborate closely with hardware, software and product teams so firmware integrates into a coherent system
• Mentor engineers on platform-level thinking, and raise the team's shared technical baseline

【Essential Requirements】

• Bachelor's or Master's degree in Computer Science, Electrical Engineering, or a related field
• Deep STM32 low-level expertise (Cortex-M4/M7, e.g. the H7 series): memory map, linker scripts, DMA, bootloader
• Hands-on BLE protocol stack experience: GATT, connection parameters, and multi-role RF coexistence
• ESP32 mass-production experience (ESP-IDF), including dual-chip inter-processor protocols over SPI/UART
• RTOS proficiency (FreeRTOS)
• Hardware circuit literacy: able to read schematics, give firmware-perspective input on circuit design, and do hands-on rework (soldering, jumper wires) — this is essential for new-platform bring-up and working with EE
• A track record of architecture refactoring: you have taken over an existing codebase and cleaned up its technical debt — not only greenfield development
• Strong C/C++, with system-level design capability and the judgement to lead complex technical decisions

【Desirable Requirements】

• Platform & architecture

- Mass-production experience with Airoha or other Bluetooth audio SoCs

- Experience designing HAL / platform abstraction layers

- Communication-protocol design and version governance experience

- Firmware OTA update architecture design, ideally adopted across an entire product line

- Broad multi-vendor MCU porting and bring-up experience (ST, TI, NXP, Nuvoton), including porting an RTOS/OS across platforms

• Audio & USB

- USB device development (CDC / DFU) — connects directly to the firmware-update toolchain

- USB Audio Class (UAC): driverless multi-channel capture/playback, streaming interfaces, real-time timing control

- Audio product background (A2DP, latency sensitivity)

• Productisation & certification

- Power management for battery-powered products: charge/discharge control, power sequencing, thermal management

- Experience taking products through international standards / alliance certification (e.g. Bluetooth SIG)

- IoT product development and AI integration experience

• AI engineering practice (we weigh this heavily)

- Proven hands-on experience applying AI to real engineering work: you use AI coding agents (Claude Code, Codex) and agentic workflows as an integral part of daily development — coding, code review, debugging, documentation, test automation — and can demonstrate concrete productivity or quality gains, beyond personal experimentation

【Soft Skills & Values】

• Total ownership and high responsibility
• Strong communication and leadership — this role influences without direct authority
• Willingness to take risks, with a sense of urgency
• Competent in project, process and risk management