configure-container

/configure:container

Check and configure comprehensive container infrastructure against project standards with emphasis on minimal images, non-root users, and security hardening.

When to Use This Skill

Use this skill when...	Use another approach when...
Auditing container infrastructure compliance (Dockerfile, workflows, scanning)	Writing a Dockerfile from scratch (/configure:dockerfile)
Checking multi-stage builds, non-root users, and security hardening	Configuring Kubernetes deployments (/configure:skaffold)
Setting up container build workflows with GHCR and multi-platform support	Running vulnerability scans on a built image (Trivy CLI directly)
Verifying .dockerignore, OCI labels, and base image versions	Configuring devcontainer features for VS Code
Adding Trivy/Grype scanning to CI pipelines	Debugging container runtime issues (system-debugging agent)

Context

• Dockerfiles: !find . -maxdepth 2 \( -name 'Dockerfile' -o -name 'Dockerfile.*' -o -name '*.Dockerfile' \)
• Docker ignore: !find . -maxdepth 1 -name '.dockerignore'
• Container workflows: !find .github/workflows -maxdepth 1 \( -name '*container*' -o -name '*docker*' -o -name '*build*' \)
• Devcontainer: !find .devcontainer -maxdepth 1 -name 'devcontainer.json'
• Skaffold: !find . -maxdepth 1 -name 'skaffold.yaml'
• Package files: !find . -maxdepth 1 \( -name 'package.json' -o -name 'pyproject.toml' -o -name 'Cargo.toml' -o -name 'go.mod' \)
• Project standards: !find . -maxdepth 1 -name '.project-standards.yaml'

Parameters

Parse from command arguments:

• --check-only: Report compliance status without modifications (CI/CD mode)
• --fix: Apply fixes automatically without prompting
• --component <name>: Check specific component only (dockerfile, workflow, registry, scanning, devcontainer)

Security Philosophy

Minimal Attack Surface: Smaller images = fewer vulnerabilities. Use Alpine (~5MB) for Node.js, slim (~50MB) for Python.

Non-Root by Default: ALL containers MUST run as non-root users.

Multi-Stage Required: Separate build and runtime environments. Build tools and dev dependencies should NOT be in production images.

Execution

Execute this container infrastructure compliance check:

Step 1: Detect container-related files

Search for Dockerfile, workflow files, devcontainer config, and .dockerignore. Detect the project type (frontend, python, go, rust, infrastructure) from package files.

Step 2: Look up latest base image versions

Use WebSearch or WebFetch to verify current versions before flagging outdated images:

1. Node.js Alpine images: Check Docker Hub for latest LTS Alpine tags
2. Python slim images: Check Docker Hub for latest slim tags
3. nginx Alpine: Check Docker Hub for latest Alpine tags
4. GitHub Actions: Check release pages for latest action versions
5. Trivy: Check aquasecurity/trivy-action releases

Step 3: Analyze each component

Check each component against standards:

Dockerfile Standards:

Check	Standard	Severity
Exists	Required for containerized projects	FAIL if missing
Multi-stage	Required (build + runtime stages)	FAIL if missing
HEALTHCHECK	Required for K8s probes	FAIL if missing
Non-root user	REQUIRED (not optional)	FAIL if missing
.dockerignore	Required	WARN if missing
.dockerignore Dockerfile*	Use glob to exclude all Dockerfile variants from context	WARN if only Dockerfile
Base image version	Latest stable (check Docker Hub)	WARN if outdated
Minimal base	Alpine for Node, slim for Python	WARN if bloated

Base Image Standards (verify latest before reporting):

Language	Build Image	Runtime Image	Size Target
Node.js	node:24-alpine (LTS)	nginx:1.27-alpine	< 50MB
Python	python:3.13-slim	python:3.13-slim	< 150MB
Go	golang:1.23-alpine	scratch or alpine:3.21	< 20MB
Rust	rust:1.84-alpine	alpine:3.21	< 20MB

Security Hardening Standards:

Check	Standard	Severity
Non-root USER	Required (create dedicated user)	FAIL if missing
Read-only FS	--read-only or RO annotation	INFO if missing
No new privileges	--security-opt=no-new-privileges	INFO if missing
Drop capabilities	--cap-drop=all + explicit --cap-add	INFO if missing
No secrets in image	No ENV with sensitive data	FAIL if found

Build Workflow Standards:

Check	Standard	Severity
Workflow exists	container-build.yml or similar	FAIL if missing
checkout action	v4+	WARN if older
build-push-action	v6+	WARN if older
Multi-platform	linux/amd64,linux/arm64	WARN if missing
Build caching	GHA cache enabled	WARN if missing
Security scan	Trivy/Grype in workflow	WARN if missing
id-token: write	Required when provenance/SBOM configured	WARN if missing
Cache scope	Explicit scope= for multi-image builds	WARN if missing
Scanner pinned	Trivy/Grype action pinned by SHA (not @master)	WARN if unpinned

Container Labels Standards (GHCR Integration):

Check	Standard	Severity
org.opencontainers.image.source	Required - Links to repository	WARN if missing
org.opencontainers.image.description	Required - Package description	WARN if missing
org.opencontainers.image.licenses	Required - SPDX license	WARN if missing

Run /configure:dockerfile for detailed Dockerfile checks if needed.

Step 4: Generate compliance report

Print a formatted compliance report:

Container Infrastructure Compliance Report
==============================================
Project Type: frontend (detected)

Component Status:
  Dockerfile              PASS
  Build Workflow          PASS
  Registry Config         PASS
  Container Scanning      WARN (missing)
  Devcontainer           SKIP (not required)
  .dockerignore          PASS

Dockerfile Checks:
  Multi-stage             2 stages          PASS
  HEALTHCHECK             Present           PASS
  Base images             node:22, nginx    PASS

Build Workflow Checks:
  Workflow                container-build.yml PASS
  checkout                v4                PASS
  build-push-action       v6                PASS
  Multi-platform          amd64,arm64       PASS
  GHA caching             Enabled           PASS

Container Labels Checks:
  image.source            In metadata-action PASS
  image.description       Custom label set  PASS
  image.licenses          Not configured    WARN

Recommendations:
  - Add org.opencontainers.image.licenses label to workflow
  - Add Trivy or Grype vulnerability scanning to CI

Overall: 2 warnings, 1 info

If --check-only, stop here.

Step 5: Apply fixes (if --fix or user confirms)

1. Missing Dockerfile: Run /configure:dockerfile --fix
2. Missing build workflow: Create from template in REFERENCE.md
3. Missing scanning: Add Trivy scanning job
4. Missing .dockerignore: Create standard .dockerignore from REFERENCE.md
5. Outdated actions: Update version numbers

Step 6: Update standards tracking

Update .project-standards.yaml:

components:
  container: "2025.1"
  dockerfile: "2025.1"
  container-workflow: "2025.1"

For detailed templates (Dockerfile, workflow, devcontainer, .dockerignore), see REFERENCE.md.

Agentic Optimizations

Context	Command
Quick compliance check	/configure:container --check-only
Auto-fix all issues	/configure:container --fix
Dockerfile only	/configure:container --check-only --component dockerfile
Workflow only	/configure:container --check-only --component workflow
Scanning only	/configure:container --fix --component scanning
Find all Dockerfiles	find . -maxdepth 2 \( -name 'Dockerfile' -o -name 'Dockerfile.*' \) 2>/dev/null

Flags

Flag	Description
--check-only	Report status without offering fixes
--fix	Apply fixes automatically
--component <name>	Check specific component only (dockerfile, workflow, registry, scanning, devcontainer)

Component Dependencies

Container Infrastructure
├── Dockerfile (required)
│   └── .dockerignore (recommended)
├── Build Workflow (required for CI/CD)
│   ├── Registry config
│   └── Multi-platform builds
├── Container Scanning (recommended)
│   └── SBOM generation (optional)
└── Devcontainer (optional)
    └── VS Code extensions

Notes

• Multi-platform builds: Essential for M1/M2 Mac developers and ARM servers
• GHCR: GitHub Container Registry is preferred for GitHub-hosted projects
• Trivy: Recommended scanner for comprehensive vulnerability detection
• Alpine vs Slim: Use Alpine for Node.js/Go/Rust. Use slim (Debian) for Python (musl compatibility issues)
• Non-root is mandatory: Never run containers as root in production
• Version pinning: Always use specific version tags, never latest

See Also

• /configure:dockerfile - Dockerfile-specific configuration
• /configure:workflows - GitHub Actions workflow configuration
• /configure:skaffold - Kubernetes development configuration
• /configure:security - Security scanning configuration
• /configure:all - Run all compliance checks
• container-development skill - Container best practices
• ci-workflows skill - CI/CD workflow patterns