Hardened alpine linux baseimage for Docker.

Note: If you use Golang, build statically and use iron-scratch. If you are using Java/Python/NodeJS/dotnet, use a distroless image instead.

# you can pull a global version (3), a series version (3.13) or a specific version (3.13.2)
docker pull ghcr.io/ironpeakservices/iron-alpine/iron-alpine:3
docker pull ghcr.io/ironpeakservices/iron-alpine/iron-alpine:3.13
docker pull ghcr.io/ironpeakservices/iron-alpine/iron-alpine:3.13.2

• ca-certificates included
• /app for everything app-related; /app/conf, /app/tmp, /app/data
• no interactive shells for users
• removed unneccessary accounts, only 'app' and 'root' users
• removed crontabs
• removed dangerous commands and utilities
• strictened permissions on system files and directories
• removed temporary shadow/passwd/group
• removed suid/guid files
• removed init scripts
• removed kernel tunables
• removed /root/
• removed fstab
• post-install.sh:
  • removes apk manager after installation
  • sets permissions on /app after installation

docker pull ghcr.io/ironpeakservices/iron-alpine:1.0.0

See the nginx example.

Updates to the official alpine docker image are automatically created as a pull request and trigger linting & a docker build. When those checks complete without errors, a merge into master will trigger a deploy with the same version to packages.

If you want, you can also enable vulnerability scanning during your build (for free). Take a look at https://github.com/aquasecurity/microscanner