Embedded Systems Engineer (Freelance)

About the role
We're building RADO, a smart outdoor advertising enclosure, and are looking for an experienced Embedded Systems Engineer. We've already finalized the core architecture and components - this role is focused execution, not a complete open-ended R&D.

Scope (2 milestones)

Milestone 1 - Core firmware (remote-friendly, ~2–3 weeks)

• Build ESP32 firmware: reed-switch wake trigger, RC522 RFID read, deep-sleep power management
• Implement MQTT/HTTP communication to our cloud backend (status updates, tag reads, device health)
• Establish local communication between ESP32 and the Huidu HD-C16L media controller
• Deliver a working demo on breadboard/dev-kit hardware

Milestone 2 - Pilot integration (onsite required, ~1 week)

• Integrate and test the validated firmware in our first fabricated enclosure
• Confirm RFID read reliability, reed-switch placement, and wiring in real conditions
• Debug and resolve any real-world issues (power draw, mounting tolerances, connectivity)
• Deliver a working end-to-end unit and brief documentation

Requirements

• Hands-on experience with ESP32 (required) - Arduino/ESP-IDF
• Experience with RFID/NFC modules (RC522 or similar), GPIO, sleep/wake power management
• Working knowledge of MQTT, HTTP/REST, and connecting embedded devices to a cloud backend
• Comfortable reading vendor hardware documentation and debugging serial/network protocols independently
• Based in or able to work onsite for Milestone 2

Nice to have

• Experience with LED display controllers (Huidu, NovaStar, Colorlight, or similar)
• Experience with production/field-deployed IoT hardware (not just prototypes/hobby projects)

Structure: Payment split across the two milestones, not a flat monthly rate - you're paid on delivery of each working demo, not time logged.