s6

Spec sheet

Purpose

s6 is a small suite of UNIX programs for process supervision and low-level administration of processes and services.Read 9 Oct 2026 · skarnet.org

Integrations

Related projects include s6-linux-init, s6-rc, s6-frontend, and s6-overlay for Docker images.Read 9 Oct 2026 · skarnet.org

Security

The s6 page describes the suite as small and secure and lists utilities for access control and privilege handling; it does not state a security certification.Read 9 Oct 2026 · skarnet.org

License

s6 is free software available under the ISC license.Read 9 Oct 2026 · skarnet.org

Dependencies

Building s6 requires skalibs 2.15.1.0 or later, and execline is recommended for full functionality.Read 9 Oct 2026 · skarnet.org

Distribution

The maker lists release 2.15.1.0 and provides the source repository plus Codeberg, GitHub, and SourceHut mirrors.Read 9 Oct 2026 · skarnet.org

Documentation and support

The maker provides self-contained documentation, points to a supervision mailing list and an OFTC IRC channel, and lists a contact email on skarnet.org.Read 9 Oct 2026 · skarnet.org

Logging

Its utilities include s6-log and tools for syslog-like functionality.Read 9 Oct 2026 · skarnet.org

Platform requirements

Installation requires a POSIX-compliant system with a standard C development environment and GNU make 3.81 or later.Read 9 Oct 2026 · skarnet.org

Privilege handling

The suite can provide controlled privilege gain without using setuid programs.Read 9 Oct 2026 · skarnet.org

Readiness

s6 provides reliable service readiness notification, which can serve as the basis for service dependency management.Read 9 Oct 2026 · skarnet.org

Service control

Its supervision system maintains a supervision tree and provides tools to control processes and monitor service states.Read 9 Oct 2026 · skarnet.org

Socket activation

s6 supports fd-holding for socket activation without requiring application code changes, linking servers to a specific library, or switching init systems.Read 9 Oct 2026 · skarnet.org

Plans and prices

Every s6 plan and price →

Where Specifiction places it

• Process Monitoring Software#23 of 267.2