What did debian ever do for us?

Wookey, wookey@wookware.org

History

• Started in 1993
• Package manager!
• Known for: stability, long hw support, upgrades that work, consistent policy, lots of software (20,000 source, 60,000 binary)
• Community/Independent distro - no one company
• Trusted not to make profit-driven choices

What makes the distro special

• Whole ecosystem
• Policy/consistency
• Derivatives encouraged
• Ports - whatever (enough) people will maintain (release(9)/non-release(13)).
• Free software. Free tools, free infrastructure.
• Some non-free packages (firmware, drivers, some software)
• No 2nd-class packages.

Debian likes to do things properly

• Multiarch
• Redproducible builds
• Bootstrapping -> Build profiles

More than just a distro

• Distro
• Project
• Community

Project

• Social Contract, DSFG definition
• Constitution, decision-making
• ~1000 Developers all over the world

Organisation

Community

• Open development
• We don't hide problems
• Users can easily get involved
• Friends, marriages
• Welcoming culture (much improved!)

What distros are there?

• Over 100 derivatives
• Notable:
  Ubuntu, Tails, Rasbian, Grml, Knoppix, Kali, Purism PureO
• Transitive derivatives
https://wiki.debian.org/Derivatives/Census
• Blends
  Astronomy, Medical, Junior, Edu, Freedombox
  https://www.debian.org/blends/

Ecosystem

• Commerce in around debian
• Ubuntu, purism, credativ, embedded, assorted consultants
• Reliable base, work only on customisations
• 21% of websites (58% Debian+Ubuntu) (w3tech 2019)
• dpkg-vendor allows upstreaming of customisations

Research playground

• clang.debian.org - 32757 packages rebuilt. 1314 (4 %) failed.
• sources.debian.org
  grep the world (6000 packages mention time_t) codesearch.debian.net
• New gcc rebuilds
• Dependency solver research. mancoosi.

ARM ports

how do I build a package?

• Rather too many ways :-)
  
• dpkg-buildpackage, debuild, git-buildpackage
• sbuild, pbuilder
• local, chroots, containers

apt source <package>
apt build-dep <package>
cd <package-version>
dpkg-buildpackage

how do I build an official package?

• Official buildds
• Clean builds - Source-only uploads
• Build everything: reautoconf, docs
• Machine-learning is problematic

Crossbuilding for free

• Cross-toolchains in archive
• Support added in last few years
• 67% of archive crosses now.

apt install crossbuild-essential-arm64
dpkg --add-architecture arm64
apt source <package>
apt build-dep -a arm64 <package>
cd <package-version>
dpkg-buildpackage -a arm64

Terminology

• Suites = unstable, testing, stable
• Codenames = sid, etch, wheezy, buster
• Releases = debian8, debian 8.1 or 8r1
• Ports = Architectures

Packaging formats

• 1.0: release tarball+big patch (tarball)
• 3.0 quilt: release tarball + quilt patch stack (tarball)
• Increasingly anachronistic (no release, git)
• New workflows
• Debcheckout vs apt source
• dgit: archive repo <-> git repo interface
• Discussion on new standard practice
• Salsa.debian.org

Infrastructure

• Buildds
• Porter boxes
• Reproducible builds
• Autopackage test
• Installability tests - piuparts
• Salsa-ci (ci.debian.net)
• sources.debian.org - searchable
• snapshot.debian.org
• Lintian

How do I debug

• debug versions of all libs built, put in separate repository
• used to be foo-dbg (explicit packaging)
• now foo-dbysym (implicit packaging)
• enable debian-debug (or debian-snapshot)
  http://deb.debian.org/debian-debug
  deb http://deb.debian.org/debian-debug/ stable-debug main
  

apt update
apt install <package>-dbgsym
apt source <package>

What do you wish you knew?

• tracker.debian.org
• backports.debian.org
• Debian Developer's corner: https://www.debian.org/devel
• debian mentors (IRC and mailing list)
• debian/rules
• dpkg-buildpackge -nc
• sid==unstable

Conferences

debconf

• debconf0 2000 Bordeaux
• ...
• debconf19 Curitiba, Brazil
• debconf20 Haifa, Israel
• Remote access taken quite seriously. Own camera gear.
• debconf video site
• IRC back in per room for questions.

minidebconf

several/year
• 2019: France, Germany, Switzerland, Singapore
• 2017: Kosovo, Colombia, Brazil, France, UK

What work are we doing currently?

• buildd admin
• File and fix bugs
• Explain packaging
• installer changes
• NN packaging
• Coresight support
• Kernel Backports

What work will we be doing next?

• 128bit pointers bootstrap
• 64-bit time_t

Any pain-points, things to fix that could make work easier?

• Get arm to put out native-built software (everything has to be un-crossed).
• Free drivers for mali