praekeltfoundation/alpine-buildpack-deps repository overview

⁠alpine-buildpack-deps

An attempt at a "buildpack-deps"-like Docker image with Alpine Linux

⁠Images

The base image is the official Docker Alpine image⁠.

This repo contains a set of images similar to the official buildpack-deps⁠ images.

⁠Caveats

• A best effort was made to find equivalent Alpine packages for the Debian packages in the official buildpack-deps. The packages may not always be 100% equivalent.
• The code you're compiling in buildpack-deps could make assumptions about the host that are not necessarily true for Alpine Linux. For example:
  • That the standard Unix tools are the GNU implementations
  • That the standard C library is glibc
  • That the paths to development files are the Debian paths
• The default/latest tag for this image is not smaller than the Debian/Ubuntu-based buildpack-deps images, although it is roughly the same size (~190MB compressed, ~660MB uncompressed). The reason for this is that the Alpine development libraries for PostgreSQL and MySQL are significantly bigger than the Debian ones. If you are hoping to make a small "buildpack-deps"-based Docker image, you're probably doing Docker images wrong.

⁠Packages

The packages in the curl and scm variants mostly have the same names in Alpine Linux as they do in the Debian/Ubuntu source. The translation of packages for the latest image is a bit more complicated, though. The packages used are listed below.

⁠curl

Upstream⁠

Additionally, we install the tar package in the curl image. This installs the GNU version of tar, which has more features than the BusyBox tar provided with Alpine Linux. In particular, the --strip-components option only available in GNU tar is commonly used in the Docker official images when extracting source code from tarballs.

*Alpine Linux uses BusyBox which includes an implementation of wget. In order for this wget to verify certificates, the libressl (Alpine 3.5+) or openssl package is required, both of which include a certificate bundle. The ca-certificates package also includes a certificate bundle and is required for Curl to be able to verify certificates.

⁠scm

Upstream⁠

*bzr was removed⁠ from the latest buildpack-deps variants. Starting with Alpine 3.7, bzr is not present in alpine-buildpack-deps either.

⁠latest

Upstream⁠

*Alpine Linux doesn't have development packages for MySQL or PostgreSQL that include only the headers/libraries necessary for client-side libraries. These Alpine packages are quite large because they include server headers/libraries as well.

**Alpine Linux switched from OpenSSL to LibreSSL⁠ in version 3.5.