Firmware, microcontrollers, sensors and connected-device bugs.
Our dosing controllers ran for weeks, then locked themselves out on day 49. The interval check compared now >= lastRun + interval, which breaks when the sum wraps past 2^32 milliseconds. How we proved it with a simulated clock and fixed it with unsigned subtraction.
Our greenhouse sensor boards boot-looped the moment WiFi.begin() ran, logging Brownout detector was triggered. The 3.3 V rail sagged under Wi-Fi transmit peaks from an undersized LDO and thin cable. How we measured it, fixed the power path and why disabling the detector is the wrong fix.
Multi-camera computer vision at a stadium or arena cannot depend on the venue's uplink. Here is how we split work between an on-site GPU edge and the cloud, the bandwidth and latency math behind it, and the failure modes we design for: WAN loss, GPU faults, clock drift and bad models.
The Cyber Resilience Act is now law and the first deadline is in September 2026. For a team shipping connected devices on embedded Linux, this is what the regulation asks of the OS layer, how Yocto and Ubuntu Core each help or leave work to you, and a CI pipeline that produces the evidence.