2017 Look ahead



  • teaching people to write reproducible code
  • SOURCE_PREFIX_MAP spec done
  • document all indirect highly valuable side-effcts of reproducible-builds

policy & law

  • uk demands reproducible firmware by law from HUAWEI
  • china asks the same from cisco


  • reproducible summit 3 2017
  • more talks at conferences around the world
  • reproducible hacking sprint 2017 (hackotlaw)
  • whitepapers and academic research
  • explain r-b to my grandmother/grandparent/grandchild in 5 sentences
  • all conferences have r-b tracks
  • start outreach to embedded device manufacturers
  • “reproducibility” is discussed as a new aspect of software trust (e.g., in security/privacy circles)

distro specific

  • debian-policy packages should be reproducible

generic/all distro

  • members from all distros
  • all distro package managers know about reproducible builds
  • post list of funded reproducibility projects


  • shouting loudly to upstreams
  • interest outside floss projects (closed software, internal development)
  • we will have convinced industry reproducibility is important
  • “ecosystem janitor team”: group to make sure upstream sources remain available & mirrored with checksum
  • collaboration between industry and community much more significant
  • google chrome is reproducible and user verifyable
  • upstreams should be encouraged to issue a statement about reproducibility of their systems


  • get as many people supporting bootstrapping efforts as we have reproducible people now
  • reproducible builds is explained in CS courses
  • we have a logo



  • meetings
    • regular 2-month IRC/voice meeting
    • more reproducible builds cross-project in person meetings
    • small 3-5 person hack sessions targeting specific goals
  • network tooling/services
    • a community of “rebuilers”(?) publishing logs about rebuilds exists
    • central webservice for submitting/retrieval of =.buildinfo= files
  • untitled column
    • more embedded dev work in the community
  • collaboration
    • =notes.git= will be more widely shared among distros
    • have more reproducibility teams in other distros
    • cross-distro outreach


  • reproducible-builds.org
    • move content from debian pages to r-b.org
    • common place for all repro builds talks that everyone uses
    • there will be a “get involved” section
    • common (cross-distro) =.buildinfo= format specification written
    • blog planet/aggregator
    • we built a standard base for =.buildinfo= files
    • all cross-project tools documented not in specific projects only
  • projects or distributions
    • fedora reproducible docs on how to reproduce builds
    • produce a template for projects that wish to make a public statement about reproducibility
    • link to Nix docs from r-b.org
    • improved RB-related doc on Bazel website
    • how to attach signatures without disrupting reproduce? guidelines for packagers.
  • untitled columns
    • searchable database of reproducibility issues (e.g. manpages)
    • examples of non-reproducibility problems explained (3-4 package examples — what did it cause?)
    • the FAQ section will be full of tips on how to use various tools in a reproducible way
    • Encyclopedia for working around common non-repro issues
    • index collection with repro issues and solutions with search
    • reproducible docs as manpages
    • HOWTO about creating reproducible packages
    • teach people how to easily build and test existing software
    • document setting up tests.r-b.org type infrastructure



  • upstream projects adopting SOURCE_PREFIX_MAP
  • reproducibility stats collected and reported (for debian, freebsd, macports, openwrt/lede, coreboot, netbsd, f-rdoird, arch linux, etc)
  • upstream git repos pass ???_ commits after cutoff date
  • reproducible iso images
  • all distros publish a statement about reproducibility


  • reproducible base system 100%
  • freebsd packages 90% reproducible by default (by count of pkgs)
  • all reproducible build options on by default
  • expectation for reproducibility understood by freebsd committers

other distros

  • macports will be 50% reproducible by count of pkgs
  • get gentoo on board!
  • more distros and FLOSS OSes join reproducible builds
  • OpenWrt & LEDE to 90% RB
  • proprietary software incorporating reproduciblity
  • first 100% reproducible OS (with packages too)
  • reproducible pkg src packages


  • support for .buildinfo in necessary tools
  • common discussion space for sharing problems and solutions
  • some simple RPM pkgs already reproducible
  • tools to reproduce


  • GNU Guix will have measurements of pkg reproducibility
  • GNU Guix will have fixed repro issues in core packages: guile, python, gcc


  • debian unstable is 95% reproducible
  • maintainers WANT to make reproducible debs
  • .buildinfo in archive
  • block debian testing migration on reproducibility regressions

Arch Linux

  • write documentation
  • tools for users to verify reproducibility
  • 100% reproducible core repo


  • reach milestone: make NixOS minimal ISO (+al deps) reproducible
  • Hydra (CI): graph or reproducibility progress
  • write nixpkgs documentation
  • investigate reproducibility for OSX in nixpkgs
  • nix: allow users to configure desired trust level (i.e. “wont only want only binaries builtby N out of K builders)
  • provide a verifiable bootstrap chain in nixpkgs going back ~10 years



  • How can we improve trust in hardware?
  • Open Hardware Specs
  • Reproducible RISC-V implementation on FPGA
  • Where are reproducible/verifiable CPUs/microchips?
  • Reproducible HDL synthesis deemed feasible
  • Will have built/ported a free system to OpenRISC
  • How do we improve trust in our networking hardware?


  • Binary blobs are evil – how do we get more open source firmware?
  • Reproducible OS images
  • Tool to generate reproducible image
  • How can end-users verify their firmware?
  • Can we convince companies to open source firmware?
  • Can we have firmware audits with checksums by independent third parties?
  • We have more Laptops supported without Management Engine

Internet of Things

  • We will have first devices with >= 50% reproducible software
  • Security updates for IoT devices will be a thing
  • There will be massive IoT botnets
  • Governments should force IoT manufacturers into maintenance!
  • Devices should be sold with clear maintenance period labels
  • Yocto/OpenEmbedded builds provide .buildinfo & are reproducible


  • Convince manufacturers to give out reproducible firmware
  • Start conversations with vendors over benefits of reproducibility
  • Talk to OEMs/ODM/…


Metadata, etc.

  • PoC for apt to verify signature by multiple rebuilders
  • buildinfo. d. n to publish buildinfo of builds it wants to have Compilers
  • GCC patches to upstream!
  • Rush reproducibility patches (inc. buildpath indep debug info)
  • Popular toolchains (C++, Java) work reproductibly and support SOURCE_PREFIX_MAP
  • LLVM / CLANG on pair with GCC regarding reproducible “patches”
  • Ocaml has no more reproducibility issues
  • Intentional nondeterminism patches Developer utilities
  • Git properties as “secure VCS” are analysed
  • PDF generating docs reproducible!
  • R data files are reproducible
  • Strip-nondeterminism is smaller due to issues fixed “properly” Diffoscope
  • Parallel diffoscope
  • More supported file formats
  • Integration with Taskotron
  • FreeBSD pkg format
  • Waterfall/ time-series gpaph at what diffoscope is doing (like Chrome Dev tools -> Network tab)
  • Detection of order difference in many files Reprotest
  • Upstream devs are using reprotest to check for reproducibility
  • Reprotest has great usability
  • Reprotest runs on many different platforms Bootstrapping
  • Have fully mapped out bootstrapping chains for GCC, GHC, JDK, FPC, gradle, Maven
  • I want to have raised awareness about bootstrap binaries & shared work on GNU toolchain bootstrap
  • User accessible tools for fully bootstrap compilers
  • Compilers will be buildable with at least one other compiler.
  • Tool to cross-bootstrap any Debian arch .buildinfo files
  • Define a way to select which buildinfo record should be compared
  • Automated buildinfo creation/inspection/comparassion tool
  • Extra optional fields in .buildinfo to help identify more causes of unreproducibility
  • Translation tool from .buildinfo specs to Guix/Nix deriviations + vice versa Specific toolchains
  • RPM toolchain(s) analysed for sources of non-reproducibility
  • Reproducible autotools
  • Reproducible ELF Tool chains
  • No more buildpath issues (SOURCE_PREFIX_MAP widely adopted)



  • Make F-Droid.org provide simple links to reproducibility results
  • A tool to find who has been able to reproduce a package
  • Package managers allow installing reproducible packages only
  • FreeBSD pkg will policy/query for attributes like reproducibility or binary transparency
  • Users have the possibiltiy to only install reproducible packages
  • Users should be able to gather statistics about reproducibliity of packages installed on their system
  • We have a reproducible build “notary witness” server runnable by everyone
  • Tools available to give system reproducibility stats
  • F-Droid will have a binary transeparency log for all releases
  • Script to rebuild a package and compare your results against the distro’s
  • Guix will allow users to select “k of n” binary providers
  • Guix will have a “health” command listing CVEs and suspicious (non-reproducible) binaries
  • Tool for any user to execute reproduce instructions
  • Tooling to create “reproducibility transparency” logs exist


  • How to get fixes accepted by the Android Tools team at Google
  • Can a crowdsourced database of reproducibility test results limit its search space enough to be useful?
  • Will enough test infrastructure exist to establish reproducibility confidently?


Analyzing non-RB

  • Automatically classifying the causes of non-reproducibility
  • Advanced statistics (research on trends, tendencies, etc.)
  • Static Analysis in order to detect possible non-reproducible bugs in source code

Misc improvements

  • Rebuild for each variation, to detect what effects the output

Dev helping

  • Maintainers can upload packegs for repro. testing
  • Create a “fuzzing” tool to modify time/date/hostname/cwd etc. so that devs can test whether that affects them


  • Testing infra should be reproducible
  • Be able to setup tests.r-b.org locally to test patches
  • Be able to set up build for a pkg locally without whole CI infra (too)


  • ci.freebsd.org will run the testing infra for packages
  • GNU Guix will be on tests.repro-b.org
  • Measure cross-arch reproducibility of noarch RPMs

Debian tests

  • Test arch:all separately
  • Test arch:all cross-architecture
  • One build on one arch, per Jenkins.d.n job-run (not just in pairs build1+build2)

Data storage

  • PostgreSQL is used
  • Store all the build artifacts of completed builds


  • Define secure VCS (Version Control System)
  • Understand/analyze security properties of Git
  • Run transparency log for software
  • Debian FTP archive distributing build info file
  • Better cross-distro build info support
  • Design security-related logic, workflows and algorithms for buildinfo Files
  • Having more people even at the Summit
  • Crypto-signing more (reproducible) releases
  • Sharing distributed databases of hashes for reproducible releases
  • Having raised awareness of bootstrapping
  • Start working on reproducible package installs
  • Encourage projects, distros and software maintainers to publish a statement about reproducibiility of their stuff
  • Store all build outputs…run diffs later to understand more
  • Efforts on making major compilers bottstrappable has started
  • Incorporate reproduible build results into binary transparency log
  • Define schema for records so that two different paths to build same artifact looks good
  • Write SOURC_PREFIX_MAP specification
  • Push GCC guild path patches
  • Push SOURCE_PREFIX_MAP into other build tools
  • Achieve 97%+ reproducibility with build-path independence
  • Government should require r-b by law for critical infrastructure SW

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