selfchecks

Self-checks, or built-in self-checks, are diagnostic routines executed by a system or device to assess its own functioning without external input. They typically run automatically during startup or at regular intervals and report health status, readiness, or fault conditions. The aim is to detect faults early, verify critical subsystems are operating within specification, and reduce downtime or risk.

Self-checks are common in hardware and software. In hardware, power-on self-tests and built-in self-tests assess processors, memory, peripherals, and safety interlocks. In software, health checks and watchdogs monitor resources and service dependencies, often exposing health endpoints for orchestration systems. Medical devices may perform self-checks on safety channels and sensors to ensure patient safety before use.

Outcomes are reported as status codes or messages. A failed self-check may trigger alarms, prevent operation, or initiate corrective actions such as retries, reinitialization, or maintenance notices. Some systems provide remediation guidance; others require human interpretation. Self-checks can also verify updates or configurations.

Advantages include early fault detection, reduced manual testing, and improved reliability. Limitations include incomplete coverage, false positives or negatives, and added complexity. Effective implementation relies on clear standards, routine maintenance, and secure handling to prevent tampering in safety-critical systems.