Middle/Senior Manual QA Engineer with Mandarin Chinese

We are looking for a Middle / Senior Manual QA Engineer - IoT / Mandarin Chinese to validate an IoT ecosystem across physical devices, embedded firmware, communication protocols, backend services, and web/mobile applications. The role combines end-to-end quality ownership with onsite work at the client campus and communication with the China-based firmware team.

Tasks

• Perform hands-on functional and integration testing of physical IoT devices;

• Validate end-to-end workflows from device and firmware through protocols, backend APIs, and web/mobile UI;

• Install, configure, maintain, and troubleshoot devices and test environments at the client campus;

• Test MQTT, ProtoBuf, Modbus, RS485, network connectivity, firmware upgrades, and recovery scenarios;

• Investigate defects across hardware, firmware, network, backend, protocol, and UI layers;

• Clarify technical information between Mandarin- and English-speaking engineering teams.

Requirements

Requirements:

• Fluent or native Mandarin Chinese and professional working English;

• Strong Manual QA experience with complex software and hardware systems;

• Hands-on experience testing IoT, embedded, smart-home, or building-automation solutions;

• Experience with MQTT and MQTT debugging tools such as MQTTX;

• Understanding of Protocol Buffers, Modbus, RS485, REST APIs, and backend integration testing;

• Practical TCP/IP, Ethernet, Wi-Fi, DHCP, DNS/mDNS, and connectivity-troubleshooting knowledge;

• Experience testing physical hardware and embedded firmware;

• Ability to reproduce complex issues, collect logs, and produce clear defect and test documentation.

Nice to Have:

• Experience with commercial building automation systems;

• Experience testing lighting controllers, sensors, gateways, or similar embedded devices;

• Experience with OTA or firmware-upgrade testing;

• Experience with Linux, Wireshark, serial diagnostic tools, or IoT test automation.

Working Conditions:

• Work model: Onsite;

• Overlap: PST business hours;

• Target start date: October;

Benefits:

• Vacation and sick leave;

• Official state holidays;

• Professional growth through challenging projects and company-supported skills development;

• Flexible working schedule: 8 hours per day, 40 hours per week;

• Personal Career Development Plan;

• Employee support program: Discount, Care, Heals, and Legal support;

• Paid external training, conferences, and professional certifications aligned with business goals;

• Internal workshops and seminars.

Locations:

• Kirkland, WA or Bellevue, WA, United States.