No. 19of 26 ·Process Monitoring Software

s6

Linux · Self-hosted

Freedom report

Two barsScore 6.3

Free tierA free tier is on its own pricing page
Runs widely1 of 6 device platforms
DocumentedPlans, terms and facts published

s6 is ranked #19 of 26 in process monitoring software on Freedom251. It runs on Linux, Self-hosted. There is a free plan.

s6 plans and pricing

All plans

s6 Free Free software · ISC license · POSIX-compliant system required skarnet.org · 9 Oct 2026

Compared on process monitoring software

Supported platforms: POSIX-compliant systems
Service monitoring: Yes
Process controls: Yes
Activity logs: Yes

Best s6 alternatives

See all 20

Two bars Glances Free tier No. 1Free6.6 Two bars PM2 Free tier No. 2$79/mo6.6 Two bars bottom (btm) Free tier No. 3Free6.5 One bar btop Free tier No. 4Free6.4 One bar htop Free tier No. 5Free6.4 One bar Monit Free tier No. 6Free6.4

The record

Purpose: s6 is a small suite of UNIX programs for process supervision and low-level administration of processes and services.
Service control: Its supervision system maintains a supervision tree and provides tools to control processes and monitor service states.
Readiness: s6 provides reliable service readiness notification, which can serve as the basis for service dependency management.
Privilege handling: The suite can provide controlled privilege gain without using setuid programs.
Logging: Its utilities include s6-log and tools for syslog-like functionality.
Socket activation: s6 supports fd-holding for socket activation without requiring application code changes, linking servers to a specific library, or switching init systems.
Integrations: Related projects include s6-linux-init, s6-rc, s6-frontend, and s6-overlay for Docker images.
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.
License: s6 is free software available under the ISC license.
Platform requirements: Installation requires a POSIX-compliant system with a standard C development environment and GNU make 3.81 or later.
Dependencies: Building s6 requires skalibs 2.15.1.0 or later, and execline is recommended for full functionality.
Distribution: The maker lists release 2.15.1.0 and provides the source repository plus Codeberg, GitHub, and SourceHut mirrors.
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.
Price from: Free

Where it ranks on Freedom251

Best Process Monitoring Software in 2026#19 of 26

Is s6 yours?

Claim it for free: prove the domain, then correct facts, plans and screenshots. An editor reviews every change.

Claim it free Promote s6

Sources

skarnet.org/software/s6/· checked 9 Oct 2026