{"id":"serversideup-s6-overlay","name":"s6-overlay","homepage":"https://hub.docker.com/r/serversideup/s6-overlay","repo_url":"https://hub.docker.com/r/serversideup/s6-overlay","category":"infrastructure","subcategories":[],"tags":["infrastructure","containers","process-supervision","init","docker","oci"],"what_it_does":"s6-overlay is a set of components (primarily for container environments) that provides an init system for PID 1, service supervision, and orderly startup/shutdown. It integrates s6/skalibs style process supervision into containers so multiple services can be managed reliably within one image.","use_cases":["Run multiple processes in a single container while keeping correct PID 1 behavior","Supervise services and restart crashed processes inside containers","Ensure deterministic boot order and graceful shutdown hooks in Docker/OCI containers","Use s6-style readiness/lifecycle management for containerized workloads"],"not_for":["Replacing a full-featured cloud orchestrator (Kubernetes, Nomad) for scheduling and scaling","Simple single-process containers where PID 1 handling is already covered","Use cases that require a network API surface (this is infrastructure/runtime tooling, not an API service)"],"best_when":"You need robust container process supervision and lifecycle management (startup ordering, graceful shutdown, service restarts) and are comfortable configuring an init/supervision layer inside the container.","avoid_when":"You need a managed service with HTTP/SDK interfaces, or you want to avoid adding an init/supervisor layer due to complexity or operational constraints.","alternatives":["tini (minimal PID 1 reaping)","s6-supervise + standalone supervision setups","supervisord (service management in containers)","dumb-init + process manager patterns","Kubernetes-native multi-container patterns (avoid multi-process containers)"],"af_score":31.5,"security_score":37.2,"reliability_score":41.2,"package_type":"mcp_server","discovery_source":["docker_mcp"],"priority":"low","status":"evaluated","version_evaluated":null,"last_evaluated":"2026-04-04T19:57:40.135203+00:00","interface":{"has_rest_api":false,"has_graphql":false,"has_grpc":false,"has_mcp_server":false,"mcp_server_url":null,"has_sdk":false,"sdk_languages":[],"openapi_spec_url":null,"webhooks":false},"auth":{"methods":[],"oauth":false,"scopes":false,"notes":"No authentication model; it is a runtime/init overlay for containers rather than a networked API."},"pricing":{"model":null,"free_tier_exists":false,"free_tier_limits":null,"paid_tiers":[],"requires_credit_card":false,"estimated_workload_costs":null,"notes":"Typically used as open-source tooling; pricing is not applicable."},"requirements":{"requires_signup":false,"requires_credit_card":false,"domain_verification":false,"data_residency":[],"compliance":[],"min_contract":null},"agent_readiness":{"af_score":31.5,"security_score":37.2,"reliability_score":41.2,"mcp_server_quality":0.0,"documentation_accuracy":35.0,"error_message_quality":0.0,"error_message_notes":null,"auth_complexity":100.0,"rate_limit_clarity":0.0,"tls_enforcement":0.0,"auth_strength":90.0,"scope_granularity":0.0,"dependency_hygiene":45.0,"secret_handling":40.0,"security_notes":"No inherent TLS/auth features because it is not a network service. Security primarily depends on how you deploy services within the supervised environment (least privilege, secret management, image hardening). If service run scripts/logging leak environment variables or secrets, that would be an operational concern.","uptime_documented":0.0,"version_stability":55.0,"breaking_changes_history":50.0,"error_recovery":60.0,"idempotency_support":"false","idempotency_notes":null,"pagination_style":"none","retry_guidance_documented":false,"known_agent_gotchas":["Not an API/tool with callable endpoints; an agent must reason about container build/runtime configuration and filesystem-based supervision scripts rather than making requests.","Behavior depends on correct container entrypoint/PID 1 wiring and proper service directory configuration; incorrect setup can cause boot failures.","Understanding s6 supervision semantics (stages, readiness, finish) is required to avoid unintended restart/shutdown behavior."]}}