Development

This guide covers the internal architecture, conventions, and patterns for building and contributing to daemonless containers.

Architecture Overview

Image Hierarchy

graph TD
    A[freebsd/freebsd-runtime:15] --> B[daemonless/base:15]
    B --> C[daemonless/arr-base:15]
    B --> D[daemonless/nginx-base:15]
    B --> E[Direct Services]
    C --> F[radarr, sonarr, lidarr, prowlarr, jellyfin]
    D --> G[nextcloud, vaultwarden, mealie]
    E --> H[gitea, traefik, redis, transmission, etc.]

All images inherit from base:15 which provides s6 supervision and PUID/PGID support. Specialized bases add runtime dependencies:

• arr-base - .NET runtime and libraries for *arr applications
• nginx-base - nginx pre-installed for web applications

Repository Structure

Each image is a standalone git repo:

<app>/
├── Containerfile           # Build from upstream binaries (:latest tag)
├── Containerfile.pkg       # Build from FreeBSD packages (:pkg tag)
├── .woodpecker.yml         # CI/CD pipeline
├── root/                   # Files copied into container
│   └── etc/
│       ├── cont-init.d/    # Initialization scripts
│       │   └── 20-<app>    # App-specific init
│       └── services.d/     # s6 service definitions
│           └── <app>/
│               ├── run     # Service start script
│               └── run.pkg # Variant for :pkg builds (optional)
├── README.md
└── LICENSE

Labels Reference

io.daemonless.* Labels

Label	Required	Purpose	Example
io.daemonless.port	Yes	Primary listening port(s)	"7878", "80,443,8080"
io.daemonless.category	Yes	Service classification	"Media Management"
io.daemonless.packages	Yes	FreeBSD packages to install	"${PACKAGES}"
io.daemonless.volumes	No	Suggested volume mounts	"/movies,/downloads"
io.daemonless.upstream-url	No	Version check API endpoint	"https://radarr.servarr.com/v1/..."
io.daemonless.upstream-sed	No	Regex to extract version	"s/.*\"version\":\"\\([^\"]*\\)\".*/\\1/p"
io.daemonless.arch	No	Supported architecture	"amd64" (default)
io.daemonless.type	No	Image type (base images only)	"base"
io.daemonless.wip	No	Work-in-progress flag	"true"
io.daemonless.pkg-name	No	Package name for :pkg builds	"radarr"
io.daemonless.base	No	Base image type	"nginx"

Upstream Version Tracking

These labels enable automated version checking:

Label	Purpose	Example
io.daemonless.upstream-mode	Version check method	"github", "servarr", "pkg"
io.daemonless.upstream-repo	GitHub repo (for github mode)	"radarr/Radarr"
io.daemonless.upstream-url	Version API URL	"https://radarr.servarr.com/v1/..."
io.daemonless.upstream-package	Package name (for npm/pkg)	"n8n"
io.daemonless.upstream-branch	Branch to track	"develop"

Upstream Mode Values

Mode	Description
github	Check GitHub releases
github_commits	Track branch commits
servarr	Use Servarr update API
sonarr	Use Sonarr releases API
pkg	Track FreeBSD package version
npm	Check npm registry
ubiquiti	Check Ubiquiti firmware API
source	No upstream tracking

Category Values

• Media Management - radarr, sonarr, lidarr, prowlarr, overseerr
• Media Servers - jellyfin, plex, tautulli
• Downloaders - sabnzbd, transmission
• Infrastructure - traefik, gitea, woodpecker, tailscale
• Databases - redis, immich-postgres
• Photos & Media - immich-server, immich-ml
• Utilities - nextcloud, vaultwarden, mealie, n8n, smokeping

Special Annotations

For .NET applications (arr-base derivatives):

# Required in Containerfile as a label hint
LABEL org.freebsd.jail.allow.mlock="required"

# Required at runtime
podman run --annotation 'org.freebsd.jail.allow.mlock=true' ...

Containerfile Patterns

Standard Pattern (:latest)

Downloads binaries from upstream for bleeding-edge versions:

ARG BASE_VERSION=15
FROM ghcr.io/daemonless/base:${BASE_VERSION}

ARG PACKAGES="app-package dependency1 dependency2"
ARG VERSION=""
ARG UPSTREAM_URL="https://api.example.com/releases"
ARG UPSTREAM_SED="s/.*\"version\":\"\\([^\"]*\\)\".*/\\1/p"

# OCI Labels (required)
LABEL org.opencontainers.image.title="App Name"
LABEL org.opencontainers.image.description="App description"
LABEL org.opencontainers.image.source="https://github.com/daemonless/app"
LABEL org.opencontainers.image.version="${VERSION}"

# Daemonless Labels (required)
LABEL io.daemonless.port="8080"
LABEL io.daemonless.category="Category"
LABEL io.daemonless.packages="${PACKAGES}"
LABEL io.daemonless.upstream-url="${UPSTREAM_URL}"
LABEL io.daemonless.upstream-sed="${UPSTREAM_SED}"

# Environment
ENV HOME=/config

# Install packages
RUN pkg update && pkg install -y ${PACKAGES} && \
    pkg clean -ay && rm -rf /var/cache/pkg/*

# Download and install app
RUN APP_VERSION=${VERSION:-$(fetch -qo - "${UPSTREAM_URL}" | sed -n "${UPSTREAM_SED}" | head -1)} && \
    fetch -qo /tmp/app.tar.gz "https://releases.example.com/app-${APP_VERSION}.tar.gz" && \
    mkdir -p /app && \
    tar xzf /tmp/app.tar.gz -C /app --strip-components=1 && \
    rm /tmp/app.tar.gz && \
    echo "${APP_VERSION}" > /app/version

# Config directory
RUN mkdir -p /config && chown -R bsd:bsd /config /app

# Copy s6 service files
COPY root/ /
RUN chmod +x /etc/services.d/*/run /etc/cont-init.d/* 2>/dev/null || true

EXPOSE 8080
VOLUME /config

Package Pattern (:pkg)

Uses FreeBSD packages for stable, tested versions:

ARG BASE_VERSION=15
FROM ghcr.io/daemonless/base:${BASE_VERSION}

ARG PKG_NAME=app
ARG PACKAGES="app"

# Labels must match Containerfile (except pkg-specific)
LABEL io.daemonless.pkg-name="${PKG_NAME}"
LABEL io.daemonless.pkg-source="containerfile"

# Install from FreeBSD packages
RUN pkg update && pkg install -y ${PACKAGES} && \
    pkg clean -ay && rm -rf /var/cache/pkg/*

# Config directory
RUN mkdir -p /config && chown -R bsd:bsd /config

# Copy s6 service files (may use run.pkg variant)
COPY root/ /
RUN if [ -f /etc/services.d/app/run.pkg ]; then \
      mv /etc/services.d/app/run.pkg /etc/services.d/app/run; \
    fi && \
    chmod +x /etc/services.d/*/run /etc/cont-init.d/* 2>/dev/null || true

EXPOSE 8080
VOLUME /config

Multi-stage Pattern

For Node.js or compiled applications:

ARG BASE_VERSION=15
FROM ghcr.io/daemonless/base:${BASE_VERSION} AS builder

# Install build dependencies
RUN pkg update && pkg install -y node npm python3 gcc ...

WORKDIR /app

# Build application
COPY package*.json ./
RUN npm ci
COPY . .
RUN npm run build
RUN npm prune --production

# Runtime stage
FROM ghcr.io/daemonless/base:${BASE_VERSION}

ARG PACKAGES="node"

# Install runtime dependencies only
RUN pkg update && pkg install -y ${PACKAGES} && pkg clean -ay

# Copy built artifacts
COPY --from=builder --chown=bsd:bsd /app /app

COPY root/ /
RUN chmod +x /etc/services.d/*/run /etc/cont-init.d/* 2>/dev/null || true

EXPOSE 8080
VOLUME /config

Init System (s6)

daemonless containers use s6 for process supervision, providing reliable service management and flexible runtime configuration.

Why s6?

Benefit	Description
Zombie Reaping	Properly reaps zombie processes
Auto-restart	Restarts failed services automatically
Multi-process	Run helper processes alongside the main app
Privilege Drop	Drop privileges while still performing root-level init

The /init Script

The entrypoint for all containers. Responsibilities:

1. Environment Handling — Captures environment variables for supervised services
2. Networking — Configures loopback interface (lo0) for health checks
3. Initialization — Executes startup scripts in order
4. Supervision — Starts s6-svscan to manage processes

Initialization Sequence

When a container starts, /init runs scripts from these directories:

1. Built-in Init (/etc/cont-init.d/)

Part of the container image. Handles:

• Configuring the bsd user (PUID/PGID)
• Setting permissions on /config
• Generating default configuration files

2. Custom Init (/custom-cont-init.d/)

User-provided scripts. Mount your scripts here to run custom initialization:

podman run -d \
  -v /path/to/my-scripts:/custom-cont-init.d:ro \
  ghcr.io/daemonless/radarr:latest

s6 Service Files

Service Run Script

root/etc/services.d/<app>/run:

#!/bin/sh
exec 2>&1

# Wait for dependencies (optional)
# s6-svwait -U /run/s6/services/redis

cd /app
exec s6-setuidgid bsd /app/bin/app --config /config

Always use exec

The exec command replaces the shell with the application, ensuring proper signal handling and process supervision.

Init Script

root/etc/cont-init.d/20-<app>:

#!/bin/sh
echo "[init] Initializing app..."

# Create required directories
mkdir -p /config/data /config/logs
chown -R bsd:bsd /config

# Generate default config if missing
if [ ! -f /config/app.conf ]; then
    cp /app/app.conf.default /config/app.conf
    chown bsd:bsd /config/app.conf
fi

echo "[init] App initialized"

Readiness Check

For services that need health checks before reporting ready:

#!/bin/sh
exec 2>&1

# Signal readiness when health endpoint responds
s6-ready-when "curl -sf http://localhost:8080/health" &

cd /app
exec s6-setuidgid bsd /app/bin/app

Environment Variables

Base Container

Variable	Default	Purpose
PUID	1000	User ID for bsd user
PGID	1000	Group ID for bsd group
TZ	UTC	Timezone

Logging (s6)

Variable	Default	Purpose
S6_LOG_ENABLE	1	Enable s6-log
S6_LOG_DEST	/config/logs/daemonless	Log directory
S6_LOG_MAX_SIZE	1048576	Max log file size (1MB)
S6_LOG_MAX_FILES	10	Rotated files to keep
S6_LOG_STDOUT	1	Mirror logs to stdout

Log Locations:

Location	Description
/config/logs/daemonless/<app>/	s6 system logs (stdout/stderr)
/config/logs/	Application-specific logs
podman logs <container>	Console output (still works)

Viewing Logs:

# Podman logs (live)
podman logs -f radarr

# s6 logs (rotated files)
tail -f /data/config/radarr/logs/daemonless/radarr/current

# Application logs
ls /data/config/radarr/logs/

s6-log automatically rotates when files reach S6_LOG_MAX_SIZE. Old logs are named with timestamps and kept up to S6_LOG_MAX_FILES.

.NET Applications

Variable	Default	Purpose
CLR_OPENSSL_VERSION_OVERRIDE	35	OpenSSL version hint
DOTNET_SYSTEM_NET_DISABLEIPV6	1	Disable IPv6 in .NET
HOME	/config	.NET home directory

Build System

The Daemonless project uses dbuild as its primary build engine. dbuild handles the full lifecycle of an image, from initial build to integration testing and publishing.

Local Building

To build an image locally, navigate to the image repository and use dbuild:

cd daemonless/radarr

# Build all variants (latest, pkg, pkg-latest)
dbuild build

# Build a specific variant
dbuild build --variant latest

# Build and run tests
dbuild build --variant latest
dbuild test --variant latest

CI/CD Pipeline

Standard .woodpecker.yaml for a new image repository:

steps:
  - name: pipeline
    image: ghcr.io/daemonless/base:15
    environment:
      GITHUB_TOKEN: { from_secret: GITHUB_TOKEN }
      GITHUB_ACTOR: { from_secret: GITHUB_USER }
    commands:
      - dbuild ci-run --prepare

The dbuild ci-run command handles environment preparation, multi-variant building, CIT testing, pushing to the registry, and SBOM generation.

Adding a New Image

1. Create Repository

mkdir myapp && cd myapp
git init

2. Initialize with dbuild

dbuild init --woodpecker

This creates a starter Containerfile, .daemonless/config.yaml, and .woodpecker.yaml.

3. Configure Containerfile

Required labels for dbuild to function correctly:

LABEL io.daemonless.port="8080"
LABEL io.daemonless.category="Utilities"
LABEL io.daemonless.packages="${PACKAGES}"

4. Create Service Files

mkdir -p root/etc/services.d/myapp root/etc/cont-init.d

5. Test Locally

# Build and test
dbuild build
dbuild test

6. Push to Registry

git add .
git commit -m "Initial myapp container"
git remote add origin git@github.com:daemonless/myapp.git
git push -u origin main

Conventions Checklist

• [ ] Use fetch instead of curl (included in FreeBSD base)
• [ ] Clean pkg cache: pkg clean -ay && rm -rf /var/cache/pkg/*
• [ ] Set ownership: chown -R bsd:bsd /config /app
• [ ] Make scripts executable: chmod +x /etc/services.d/*/run
• [ ] Use s6-setuidgid bsd in run scripts
• [ ] Create /config directory and set as VOLUME
• [ ] Keep Containerfile and Containerfile.pkg labels in sync
• [ ] Use ARG for BASE_VERSION, PACKAGES, VERSION
• [ ] Include upstream-url and upstream-sed for version detection
• [ ] Add io.daemonless.wip="true" for incomplete images

Troubleshooting

.NET Apps Won't Start

Ensure ocijail is patched and annotation is set:

./scripts/build-ocijail.sh
podman run --annotation 'org.freebsd.jail.allow.mlock=true' ...

See ocijail Patch for details.

Permission Denied

Check PUID/PGID match host user:

podman run -e PUID=$(id -u) -e PGID=$(id -g) ...

Service Not Starting

Check s6 logs:

podman exec myapp cat /config/logs/daemonless/myapp/current

Or check init output:

podman logs myapp 2>&1 | grep -A5 "\[init\]"

Build Fails on pkg install

Check package name exists:

pkg search myapp
pkg rquery '%n %v' myapp