Linux containers in 500 lines of code

This article argues that Linux containers are built from several overlapping kernel controls—namespaces, capabilities, cgroups, rlimits, and seccomp—and that understanding their boundaries is critical for running untrusted workloads safely. For CIOs and technology leaders, the strategic takeaway is that containers are not a security silver bullet: hardening requires deliberate defense-in-depth, careful treatment of user namespaces, and explicit restriction of privileges, filesystem access, and system calls to reduce blast radius and operational risk. For IT organizations, the business impact is stronger isolation for multi-tenant or sandboxed workloads, but only if platform teams standardize secure container baselines rather than relying on default container behavior.