Embedded Firmware Engineer (Access)

About Keystone AI At Keystone AI Inc., we create technology platforms for Businesses, Smart Homes, and Internet Service Providers, driven by our goal to connect everyone, everywhere. To date, Keystone AI has shipped over 100 million devices worldwide, from ISP networking products to next generation of IT solutions. Our growth is made possible by the dedicated team of hundreds behind the scenes. From software developers and product managers to designers and strategists, Team UI is driven to achieve our common goal: Rethinking IT. At Keystone AI, you’ll heighten your potential and broaden your horizons - all while shaping the future of connectivity. Keystone AI Prague R&D team is looking for experienced Embedded Firmware Engineer (Access). Candidates should be prepared to work from our Prague office at least three times per week. Responsibilities: Work as part of a global, cross-functional team of firmware, hardware, and product engineers to develop cutting-edge access control products and technologies Design, implement, and maintain embedded firmware for current and next-generation access devices (readers, hubs, controllers) Enhance and optimize existing firmware for performance, stability, and security Participate in code reviews to ensure adherence to best practices and maintain high code quality standards Collaborate closely with BSP, Hardware, Backend, Mobile, and Product Assurance (PA) teams throughout the product development lifecycle Diagnose, troubleshoot, and perform root-cause analysis of firmware and system-level issues Support manufacturing and production validation by resolving firmware-related issues and assisting with firmware update pipelines Requirement (Must-Haves): 3+ years embedded firmware development experience with C Good knowledge of network protocols (TCP/IP, HTTP, Websocket, TLS/SSL) Experience with microcontrollers, SoCs, embedded Linux and RTOS Experience with access control systems (e.g., card readers, NFC, mobile unlocking) Knowledge of Git version control system Preferred Qualifications: Experience with Linux application development and OpenWRT/Yocto build systems Good understanding of Layer 2 networking and device-to-device communication Familiarity with security best practices for IoT and access control firmware (secure boot, encrypted communication, key management) Knowledge of NFC, BLE, cryptographic algorithms, Golang, and MCU architecture is a plus Proficiency with hardware interfaces and protocols: GPIO, USB, UART, PWM, Flash, SPI, I²C, etc. Contributions to open-source embedded projects (e.g., OpenWRT, ESP-IDF, Zephyr) are a strong advantage Benefits: Competitive salary and 5 weeks of vacation per year Discretionary bonuses based on individual performance Flexible working hours, home office Top floor office with terrace and amazing view of Prague Kitchen packed with coffee, food, snacks & sodas, meal allowance, etc. A collective of developers who want to make the best product. Maximum effort to keep processes to a minimum, no complex reporting and similar habits