README.md

repro-sources-list.sh

repro-sources-list.sh configures /etc/apt/sources.list and similar files for installing packages from a snapshot to help Reproducible Builds.

# SOURCE_DATE_EPOCH is set to 1691114774 (i.e., 20230804T020614Z, timestamp of /etc/apt/sources.list)
FROM ubuntu:jammy-20230804
ENV DEBIAN_FRONTEND=noninteractive
RUN \
  --mount=type=cache,target=/var/cache/apt,sharing=locked \
  --mount=type=cache,target=/var/lib/apt,sharing=locked \
  --mount=type=bind,source=./repro-sources-list.sh,target=/usr/local/bin/repro-sources-list.sh \
  repro-sources-list.sh && \
  apt-get update && \
  apt-get install -y gcc

Examples:

• Dockerfile.debian-11
• Dockerfile.debian-12
• Dockerfile.ubuntu-2204
• Dockerfile.ubuntu-2404
• Dockerfile.archlinux

Hints

• To preserve the package cache on GHA, use https://github.com/reproducible-containers/buildkit-cache-dance. See .github/workflows/main.yaml for an example.

• For Debian >= 13 and Ubuntu >= 23.10, see also ./alternative/ to lock packages without using repro-sources-list.sh.

Environment variables

Variable	Description	Default value
SOURCE_DATE_EPOCH	Timestamp of the snapshot (int64)	Timestamp of /etc/apt/sources.list, etc. (See below)
WRITE_SOURCE_DATE_EPOCH	Write the SOURCE_DATE_EPOCH value to a file	/dev/null
SNAPSHOT_ARCHIVE_BASE	Base URL of the snapshot	http://snapshot.debian.org/archive/, etc. (See below)
BACKPORTS	Enable Debian backports	0
KEEP_CACHE	Keep apt cache	1

Distribution-specific default values:

Distribution	SOURCE_DATE_EPOCH	SNAPSHOT_ARCHIVE_BASE
Debian (<= 11)	Timestamp of /etc/apt/sources.list	http://snapshot.debian.org/archive/
Debian (>= 12)	Timestamp of /etc/apt/sources.list.d/debian.sources	http://snapshot.debian.org/archive/
Ubuntu (<= 23.10)	Timestamp of /etc/apt/sources.list	http://snapshot.ubuntu.com/
Ubuntu (>= 24.04)	Timestamp of /etc/apt/sources.list.d/ubuntu.sources	http://snapshot.ubuntu.com/
ArchLinux	Timestamp of /var/log/pacman.log	http://archive.archlinux.org/

Related project

https://github.com/reproducible-containers/repro-pkg-cache contains Dockerfile examples to reproduce package cache with specific versions, by pushing the cache to an image registry.

Project	Cache location	Best for
https://github.com/reproducible-containers/repro-sources-list.sh	Distros' permanent snapshot servers (*1)	Debian, Ubuntu, ArchLinux
https://github.com/reproducible-containers/repro-pkg-cache	Your own permanent image registry	Alpine, Fedora, Rocky, openSUSE, etc.

(*1): The packages can be also ephemerally cached on GitHub Actions to reduce loads on distros' snapshot servers. See the Hints above.