Job Details

Magical Toys is a San Francisco–based startup crafting voice-first, connected play experiences. Our current platform centers on an ESP32-S3–powered interactive toy with low-power wake-word, full-duplex audio, BLE/Wi-Fi onboarding, OTA updates, and delightful LED interactions—built to be safe, resilient, and fun.

About the Role

You'll be the go-to firmware engineer advancing our ESP32 stack for real-time audio, connectivity, and low-power operation. You'll ship features that make our characters feel alive: reliable wake-word, smooth streaming, robust provisioning, and battery-friendly behaviors. You'll work closely with hardware, audio/DSP, and mobile to iterate rapidly on product.

What You'll Do

• Develop and optimize ESP32 firmware (ESP-IDF + FreeRTOS) for connectivity, audio, and power management.
• Implement and harden Wi‑Fi (802.11) features including provisioning, secure transport, and reconnection logic.
• Integrate WebSockets (and related real-time channels) for low-latency device-cloud messaging.
• Contribute to real-time audio features: I²S pipeline, VAD/wake‑word (e.g., WakeNet), buffering, and playback.
• Enhance low-power behavior (light/deep sleep, wake sources) while meeting latency and UX targets.
• Build and maintain BLE flows (e.g., first-time onboarding, device info, diagnostics).
• Own OTA reliability (rollback, versioning, staged rollout) and on-device logging/metrics.
• Debug with logic analyzers/J-Link/serial trace; write crisp documentation and code reviews; collaborate cross-functionally.

Required Qualifications

• 3–5 years professional embedded experience (ESP32, STM32, nRF, or similar).
• Strong C/C++ in RTOS environments; comfort with ESP‑IDF, FreeRTOS, CMake, and IDF Monitor.
• Hands-on Wi‑Fi development (802.11), plus experience with real-time messaging (WebSockets/MQTT).
• Familiar with voice/wake‑word frameworks (e.g., WakeNet or equivalent) and I²S audio basics.
• Solid grasp of SPI/I²C/UART and low-level bring-up.
• Excellent problem-solving; thrives in a fast-paced, lab-centric, small-team setting.

Preferred Qualifications

• IoT security: TLS, certificate provisioning, secure boot, and flash encryption.
• Audio/DSP exposure: AEC/NS/AGC, streaming buffers, and clocking on constrained MCUs.
• Real-time comms on embedded or at the edge (e.g., RTP/WebRTC on gateway, or similar architectures).
• OTA pipelines at scale; factory firmware, self-test, or DFM/DFT collaboration.
• Contributions to open source or demonstrable personal prototypes.

Why Join Magical Toys?

• Ship tangible, joyful products that blend hardware, firmware, and a touch of wonder.
• Tight feedback loops: on-bench testing, rapid iterations, and direct impact on user experience.
• Supportive, collaborative team that values craft, balance, and growth.
• Medical Insurance Provided to full-time staff

To apply

Send your resume and a brief note on your most relevant ESP32 work (links to repos/demos welcome) to [email placeholder]. Magical Toys is an equal opportunity employer—diversity and inclusion are core to how we build.