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+#+COLUMNS: %40ITEM %10BEAMER_env(Env) %9BEAMER_envargs(Env Args) %10BEAMER_act(Act) %4BEAMER_col(Col) %10BEAMER_extra(Extra) %8BEAMER_opt(Opt)
+#+TITLE: Why we must preserve the world's software history
+#+SUBTITLE: and how Software Heritage tackles this challenge
+# #+AUTHOR: Roberto Di Cosmo
+# #+EMAIL: roberto@dicosmo.org @rdicosmo @swheritage
+#+BEAMER_HEADER: \date[15/09/2021]{15 Septembre 2021\\Ecole des Ponts}
+#+BEAMER_HEADER: \title[Preserving our software heritage~~~~ www.softwareheritage.org]{Why we must preserve the world's software history}
+#+BEAMER_HEADER: \author[R. Di Cosmo~~~~ roberto@dicosmo.org ~~~~ (CC-BY 4.0)]{Roberto Di Cosmo\\Inria and Universit\'e de Paris\vspace{-2em}}
+# #+BEAMER_HEADER: \setbeameroption{show notes on second screen}
+#+BEAMER_HEADER: \setbeameroption{hide notes}
+#+KEYWORDS: software heritage legacy preservation knowledge mankind technology
+#+LATEX_HEADER: \usepackage{tcolorbox}
+#+LATEX_HEADER: \definecolor{links}{HTML}{2A1B81}
+#+LATEX_HEADER: \hypersetup{colorlinks,linkcolor=,urlcolor=links}
+
+#
+# prelude.org contains all the information needed to export the main beamer latex source
+# use prelude-toc.org to get the table of contents
+#
+
+#+INCLUDE: "../../common/modules/prelude-toc.org" :minlevel 1
+
+
+#+INCLUDE: "../../common/modules/169.org"
+
+# +LaTeX_CLASS_OPTIONS: [aspectratio=169,handout,xcolor=table]
+
+#+LATEX_HEADER: \usepackage{bbding}
+#+LATEX_HEADER: \DeclareUnicodeCharacter{66D}{\FiveStar}
+
+#
+# If you want to change the title logo it's here
+#
+# +BEAMER_HEADER: \titlegraphic{\includegraphics[width=0.5\textwidth]{SWH-logo}}
+
+# aspect ratio can be changed, but the slides need to be adapted
+# - compute a "resizing factor" for the images (macro for picblocks?)
+#
+# set the background image
+#
+# https://pacoup.com/2011/06/12/list-of-true-169-resolutions/
+#
+#+BEAMER_HEADER: \pgfdeclareimage[height=90mm,width=160mm]{bgd}{swh-world-169.png}
+#+BEAMER_HEADER: \setbeamertemplate{background}{\pgfuseimage{bgd}}
+#+LATEX: \addtocounter{framenumber}{-1}
+* Introduction
+#+INCLUDE: "../../common/modules/rdc-bio.org::#main" :only-contents t :minlevel 2
+* Why we must preserve the history of Software Source Code
+** Software is all around us                                       :noexport:
+   #+INCLUDE: "../../common/modules/software-all-around-us.org::#softwareispervasive" :only-contents t :minlevel 3
+** Focus on the /Source Code/                                      :noexport:
+   #+INCLUDE: "../../common/modules/source-code-different-short.org::#thesourcecode" :only-contents t :minlevel 3
+** Software /Source Code/ is Precious Knowledge
+   #+INCLUDE: "../../common/modules/source-code-different-short.org::#softwareisdifferent" :only-contents t :minlevel 3
+** Calling for preservation: UNESCO
+*** :B_column:BMCOL:
+    :PROPERTIES:
+    :BEAMER_col: .53
+    :BEAMER_env: column
+    :END:
+    #+ATTR_LATEX: :width .7\linewidth
+    file:UNESCOParisCallMeeting.png
+    UNESCO, Inria, Software Heritage invite\\
+    [[https://en.unesco.org/news/experts-call-greater-recognition-software-source-code-heritage-sustainable-development][40 international experts meet in Paris]] ...
+    #+BEAMER: \pause
+*** :B_column:BMCOL:
+    :PROPERTIES:
+    :BEAMER_col: .5
+    :BEAMER_env: column
+    :END:
+    #+ATTR_LATEX: :width .65\linewidth
+    file:paris_call_ssc_cover.jpg
+    [[https://en.unesco.org/foss/paris-call-software-source-code][The call is published on Feb 2019]]\pause
+*** :B_ignoreheading:
+    :PROPERTIES:
+    :BEAMER_env: ignoreheading
+    :END:
+*** 
+    :PROPERTIES:
+    :BEAMER_COL: 1.06
+    :BEAMER_env: block
+    :END:
+    “[We call to] support efforts to gather and preserve the artifacts and
+    narratives of the history of computing, while the earlier creators are still
+    alive”
+    \vspace{10pt}
+   \hfill https://en.unesco.org/foss/paris-call-software-source-code \hfill\mbox{}
+  
+** Calling for preservation: Donald Knuth and Len Shustek
+*** Communications of the ACM, February 2021                     :B_picblock:
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=KnuthHistory.jpg, leftpic=true, width=.3\textwidth
+    :END:
+    /"Telling historical stories is the best way to teach. It's much easier to understand something if you know the threads it is connected to."/
+    \mbox{}\\
+    \mbox{}\\
+    \mbox{}\hfill /Let's Not Dumb Down the History of Computer Science/\\
+    \mbox{}\hfill Donald E. Knuth, Len Shustek\\
+    \mbox{}\hfill https://doi.org/10.1145/3442377
+#+BEAMER: \pause
+*** A unique opportunity
+    most of the creators are still here: we can talk to them!\\
+    \hfill but the clock is ticking...
+#    - Software Heritage provides a key infrastructure for software historians
+** /Source Code/ and the commons                                   :noexport:
+   #+INCLUDE: "../../common/modules/foss-commons.org::#commonsdef" :only-contents t :minlevel 3
+** Source code history for Open Science
+   #+INCLUDE: "../../common/modules/swh-ardc.org::#pillaropenscience" :only-contents t :minlevel 3
+*** 
+    \hfill Preserving the history of source code is important for /reproducibility/
+** Source code is /special/ (software is /not/ data)               :noexport:
+  # Was: #+INCLUDE: "../../common/modules/swh-ardc.org::#swnotdata" :only-contents t :minlevel 3
+*** /Executable/ and /human readable/ knowledge \hfill copyright law :noexport:
+    /“Programs must be written for people to read, and only incidentally for machines to execute.”/\\
+    \hfill Harold Abelson
+#+BEAMER: \pause
+*** Software /evolves/ over time
+    - projects may last decades
+    - the /development history/ is key to its /understanding/
+#+BEAMER: \pause
+*** Complexity :B_picblock:
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=python3-matplotlib.pdf, width=.6\linewidth
+    :END:
+    - /millions/ of lines of code
+    - large /web of dependencies/
+      + easy to break, difficult to maintain
+      + /research software/ a thin top layer
+    - sophisticated /developer communities/
+#+BEAMER: \pause
+*** The human side
+    design, algorithm, code, test, documentation, community, funding, and so many more facets ...
+** Source code history for Security and Transparency
+#+LATEX: \vspace{-.5em}
+*** Where does reused software come from?                           :B_block:
+    :PROPERTIES:
+    :BEAMER_env: block
+    :BEAMER_COL: .5
+    :END:
+#+BEGIN_EXPORT latex
+\begin{center}
+\includegraphics[width=.7\linewidth]{myriadsources}
+\end{center}
+#+END_EXPORT
+#+BEAMER: \pause
+*** Do /you/ know where it comes from?                              :B_block:
+    :PROPERTIES:
+    :BEAMER_env: block
+    :BEAMER_COL: .4
+    :END:
+    - the software you ship
+    - the software you use
+    - the software you acquire
+    - the software that 
+      + has that bug
+      + has that vulnerability
+***                                                         :B_ignoreheading:
+    :PROPERTIES:
+    :BEAMER_env: ignoreheading
+    :END:
+#+BEAMER: \pause
+*** KYSW: Know Your SoftWare                                     :B_picblock:
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=executiveorder.jpg,width=.4\linewidth,leftpic=true
+    :END:
+    Like KYC in banking, KYSW is now essential all over IT...\\
+    \mbox{}\\
+    *Sec. 4. Enhancing Software Supply Chain Security* \\
+    \hfill /ensuring and attesting, to the extent practicable, to the integrity and provenance of open source software/\\
+    \mbox{}\hfill [[https://www.whitehouse.gov/briefing-room/presidential-actions/2021/05/12/executive-order-on-improving-the-nations-cybersecurity/][May 2021 POTUS Executive Order]]
+   
+* An Endangered Knowledge
+** Spread all around                                               :noexport:
+   #+INCLUDE: "../../common/modules/swh-motivations.org::#spread" :only-contents t :minlevel 3
+** Fragile
+   \vspace{-.5em}
+   #+INCLUDE: "../../common/modules/swh-motivations.org::#fragile" :only-contents t :minlevel 3
+   \mbox{}\\
+   \hfill and what about all the landmark legacy source code that is rotting away?
+** We are at a turning point
+   #+INCLUDE: "../../common/modules/turningpoint.org::#turningpoint" :only-contents t :minlevel 3
+* How we can preserve our Software Heritage
+** Software Heritage in a nutshell \hfill www.softwareheritage.org
+#+BEAMER: \transdissolve
+#+INCLUDE: "../../common/modules/swh-goals-oneslide-vertical.org::#goals" :only-contents t :minlevel 3
+** Largest software archive, principled \hfill \url{http://bit.ly/swhpaper}
+   #+latex: \begin{center}
+   #+ATTR_LATEX: :width 0.5\linewidth
+   file:SWH-as-foundation-slim.png
+   #+latex: \end{center}
+   #+BEAMER: \pause
+   #+latex: \centering
+   #+ATTR_LATEX: :width \extblockscale{.6\linewidth}
+   file:2021-05-archive-growth.png
+   #+BEAMER: \pause
+*** Technology
+    :PROPERTIES:
+    :BEAMER_col: 0.34
+    :BEAMER_env: block
+    :END:
+    - transparency and FOSS
+    - replicas all the way down
+*** Content (billions!)
+    :PROPERTIES:
+    :BEAMER_col: 0.32
+    :BEAMER_env: block
+    :END:
+    - *intrinsic identifiers*
+    - facts and provenance
+*** Organization
+    :PROPERTIES:
+    :BEAMER_col: 0.33
+    :BEAMER_env: block
+    :END:
+    - non-profit
+    - multi-stakeholder
+** A peek under the hood: a universal archive
+    #+BEAMER: \begin{center}
+    #+BEAMER:   \mode<beamer>{\only<1>{\includegraphics[width=\extblockscale{1\textwidth}]{swh-dataflow-merkle-listers.pdf}}}
+    #+BEAMER:   \only<2-3>{\includegraphics[width=\extblockscale{1\textwidth}]{swh-dataflow-merkle.pdf}}
+    #+BEAMER: \end{center}
+#+BEAMER: \pause
+#+BEAMER: \pause
+   /Global development history/ permanently archived in a /unique/ git-like Merkle DAG
+   - *~400 TB* (uncompressed) blobs, *~20 B* nodes, *~300 B* edges
+   #   - *GitHub*, Gitlab.com, Bitbucket, /Gitorious/, /GoogleCode/, GNU, PyPi, Debian, NPM...
+** Software Heritage /intrinsic/ Identifiers (SWHID) \hfill [[https://docs.softwareheritage.org/devel/swh-model/persistent-identifiers.html][link to full docs]]
+# #+INCLUDE: "../../common/modules/swh-id-syntax.org::#swh-id-syntax" :only-contents t :minlevel 3
+  #+LATEX: \centering%\forcebeamerstart
+  #+LATEX: \mode<beamer>{\only<1>{\includegraphics[width=\linewidth]{SWHID-v1.4_1.png}}}
+  #+LATEX: \mode<beamer>{\only<2>{\includegraphics[width=\linewidth]{SWHID-v1.4_2.png}}}
+  #+LATEX: \only<3->{\includegraphics[width=\linewidth]{SWHID-v1.4_3.png}}
+  #+LATEX: %\forcebeamerend
+*** An emerging standard :B_block:
+    :PROPERTIES:
+    :BEAMER_act: <4->
+    :BEAMER_COL: .6
+    :BEAMER_env: block
+    :END:
+    - in Linux Foundation's [[https://spdx.github.io/spdx-spec/appendix-VI-external-repository-identifiers/#persistent-id][SPDX 2.2]]
+    - IANA registered, WikiData property [[https://www.wikidata.org/wiki/Property:P6138][P6138]]
+*** Examples: :B_block:
+    :PROPERTIES:
+    :BEAMER_act: <5->
+    :BEAMER_COL: .4
+    :BEAMER_env: block
+    :END:
+    - [[https://archive.softwareheritage.org/swh:1:cnt:64582b78792cd6c2d67d35da5a11bb80886a6409;origin=https://github.com/virtualagc/virtualagc;lines=245-261/][Apollo 11 AGC excerpt]],
+    - [[https://archive.softwareheritage.org/swh:1:cnt:bb0faf6919fc60636b2696f32ec9b3c2adb247fe;origin=https://github.com/id-Software/Quake-III-Arena;lines=549-572/][Quake III rsqrt]]
+* Demo time!
+** A walkthrough
+   - Browse [[https://archive.softwareheritage.org][the archive]]
+   - [[https://save.softwareheritage.org][Trigger archival]] of your preferred software in a breeze
+   - Get and use SWHIDs ([[https://docs.softwareheritage.org/devel/swh-model/persistent-identifiers.html][full specification available online]])
+   - The [[https://www.softwareheritage.org/2019/07/20/archiving-and-referencing-the-apollo-source-code/][Apollo 11 AGC source code example]]
+   - Cite software [[https://www.softwareheritage.org/2020/05/26/citing-software-with-style/][with the biblatex-software style]] from CTAN
+   - Example use in a research article: compare Fig. 1 and conclusions 
+      - in [[http://www.dicosmo.org/Articles/2012-DaneluttoDiCosmo-Pcs.pdf][the 2012 version]]
+      - in [[https://www.dicosmo.org/share/parmap_swh.pdf][the updated version]] using SWHIDs and Software Heritage
+#   - Example use in a research article: extensive use of SWHIDs in [[https://www.dicosmo.org/Articles/2020-ReScienceC.pdf][a replication experiment]]
+   - Example in a journal: [[http://www.ipol.im/pub/art/2020/300/][an article from IPOL]]
+   - [[https://doc.archives-ouvertes.fr/en/deposit/deposit-software-source-code/][Curated deposit in SWH via HAL]], see for example: 
+      [[https://hal.archives-ouvertes.fr/hal-02130801][LinBox]], [[https://hal.archives-ouvertes.fr/hal-01897934][SLALOM]], [[https://hal.archives-ouvertes.fr/hal-02130729][Givaro]], [[https://hal.archives-ouvertes.fr/hal-02137040][NS2DDV]], [[https://hal.archives-ouvertes.fr/lirmm-02136558][SumGra]], [[https://hal.archives-ouvertes.fr/hal-02155786][Coq proof]], ...
+   - Rescue landmark legacy software, see the [[https://www.softwareheritage.org/swhap/][SWHAP process with UNESCO]]
+** Summing up: a revolutionary infrastructure /designed for source code/ :noexport:
+#+latex:\vspace{-0.2em}
+#+BEGIN_EXPORT latex
+ \begin{center}
+ \includegraphics[width=.4\linewidth]{SWH-logo.pdf}
+ { \url{www.softwareheritage.org}}
+ \end{center}
+#+END_EXPORT
+#+latex:\vspace{-0.4em}
+*** /global/ source code /archive/ \hfill /Library of Alexandria of source code/
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=clock-spring-forward.png,width=.15\linewidth,leftpic=true
+    :END:
+      + harvest /all/ software source code
+      + /on demand harvesting/ and /curated deposit/
+#+latex:\vspace{-0.4em}
+*** /universal/ intrinsic identifiers
+      \mbox{}\hfill SWHID standard is independent of version control systems
+#+latex:\vspace{-0.4em}
+*** /uniform/ data model, /full graph/ of development history
+      \mbox{}\hfill enables large scale, big code research
+#+latex:\vspace{-0.4em}
+*** /infrastructure/ for Open Science
+    \mbox{} \hfill /base layer/ for software source code in the /Open Science architecture/
+* Preserving our software commons: the past
+** The \hfill /\href{https://unesdoc.unesco.org/ark:/48223/pf0000371017}{SWHAP}/ process, with UNESCO and University of Pisa
+  # variant of #+INCLUDE: "../../common/modules/swh-acquisition-process.org::#swhap" :only-contents t :minlevel 3
+*** Paris Call on Software Source Code
+    “[We call to] support efforts to gather and preserve the artifacts and
+    narratives of the history of computing, while the earlier creators are still
+    alive”
+    #+BEAMER: \pause
+***                                                             :B_block:BMCOL:
+  :PROPERTIES:
+  :BEAMER_col: 0.3
+  :END:
+#+BEGIN_EXPORT latex
+\begin{center}
+\includegraphics[width=\extblockscale{1.1\linewidth}]{SWHAP-cover.pdf}
+\end{center}
+#+END_EXPORT
+*** :B_block:BMCOL:
+  :PROPERTIES:
+  :BEAMER_col: 0.7
+  :END:
+  - **Rescue** Legacy Software from different media\\
+    \mbox{}\\
+  - **Curate** the code
+    - reconstruct the development history
+      + /Software Heritage - GitHub/ work on fixing git
+    - collect the metadata\\
+    \mbox{}\\
+  - **Archive** in Software Heritage
+*** 
+    *UNESCO, UniPi and Software Heritage* collaboration \hfill worldwide scope
+  
+** An example: TAUmus, from Pisa (70's)
+   #+INCLUDE: "../../common/modules/swh-acquisition-process.org::#swhaptaumus" :only-contents t :minlevel 3
+#+BEAMER: \pause
+\vspace{-4em}
+*** Stay tuned
+    \hfill /great news for software stories in a few months/...
+* Preserving our software commons: the present and the future
+** Focus on Academia: growing adoption (selection)
+   #+INCLUDE: "../../common/modules/swh-adoption-academic.org::#adoption" :only-contents t :minlevel 3   
+** Recent preservation news
+*** Saving 250.000 endangered repositories...
+    - summer 2019: BitBucket announce Mercurial VCS phase out
+    - fall 2019: Software Heritage teams up with Octobus (funded by NLNet, thanks!)
+    - july 2020: BitBucket erases /250.000/ repositories
+    - august 2020: [[https://bitbucket-archive.softwareheritage.org][bitbucket-archive.softwareheritage.org]] is live
+#+BEAMER: \pause
+*** ... preserving the web of knowledge   \hfill  (original tweet [[https://twitter.com/gabrielaltay/status/1300218789762662401][is here]] ) :B_picblock:
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=bitbucket_swh_praise.png, width=.6\linewidth, leftpic=true
+    :END:
+
+\\
+    *Bottomline*\\
+    /explicit deposit/ is important, ...\\
+    \mbox{}\hfill ... and we must promote it...\hfill\mbox{}\\
+    \mbox{}\hfill ... but will never be enough.\\
+\mbox{}\\
+\mbox{}\hfill /(think also of all software dependencies!)/
+* The road aheyqdiyad
+** A committed core team                                            :B_block:
+   #+ATTR_LATEX: :width .6\linewidth
+   file:team-2020.png
+# *** Team
+#    - 1.5 / 3 management - 6 / 15 dev/ops; - 1 / 4 product management
+#    - 0.5 / 4 outreach - 0.2 / 3 partnerships - 0 / support
+# #+BEAMER: \pause
+*** 
+    plus Jean-François Abramatic ...\\
+    \hfill ... and many more that are supporting our daily work (*/thanks Inria!/*)
+   
+** An international, non profit initiative\hfill built for the long term
+  :PROPERTIES:
+  :CUSTOM_ID: support
+  :END:
+*** Sharing the vision                                              :B_block:
+  :PROPERTIES:
+  :CUSTOM_ID: endorsement
+  :BEAMER_COL: .5
+  :BEAMER_env: block
+  :END:
+   #+LATEX: \begin{center}{\includegraphics[width=\extblockscale{.4\linewidth}]{unesco_logo_en_285}}\end{center}
+   #+LATEX: \vspace{-0.8cm}
+   #+LATEX: \begin{center}\vskip 1em \includegraphics[width=\extblockscale{1.4\linewidth}]{support.pdf}\end{center}
+    #+latex: \small And many more ...\\
+    #+latex:\mbox{}~~~~~~~\tiny\url{www.softwareheritage.org/support/testimonials}
+#+BEAMER: \pause
+*** Donors, members, sponsors                                       :B_block:
+    :PROPERTIES:
+    :CUSTOM_ID: sponsors
+    :BEAMER_COL: .5
+    :BEAMER_env: block
+    :END:
+   #+LATEX: \begin{center}\includegraphics[width=\extblockscale{.4\linewidth}]{inria-logo-new}\end{center}
+   #+LATEX: \begin{center}
+   # #+LATEX: \includegraphics[width=\extblockscale{.2\linewidth}]{sponsors-levels.pdf}
+   #+LATEX: \colorbox{white}{\includegraphics[width=\extblockscale{1.4\linewidth}]{sponsors.pdf}}
+   #+LATEX: \end{center}
+#   - sponsoring / partnership :: \hfill \url{sponsorship.softwareheritage.org}
+*** :B_ignoreheading:
+    :PROPERTIES:
+    :BEAMER_env: ignoreheading
+    :END:
+*** Research collaboration                              :B_picblock:noexport:
+  :PROPERTIES:
+  :BEAMER_COL: .5
+  :BEAMER_env: picblock
+  :BEAMER_OPT: pic=Qwant_Logo, leftpic=true
+  :END:
+    source code search engine
+*** See more                                                       :noexport:
+    \hfill\tiny\url{http:://www.softwareheritage.org/support/testimonials}
+*** Global network                                      :B_picblock:noexport:
+    :PROPERTIES:
+    :BEAMER_COL: .5
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=fossid, leftpic=true, width=.3\linewidth
+    :END:
+     - first *independent mirror*
+     - increased reliability
+** You may help!
+*** Foster adoption and best practices
+      + [[https://www.softwareheritage.org/save-and-reference-research-software/][archive and reference relevant source code]] (save code now, and [[https://hal.inria.fr/hal-01872189][deposit]])
+      + use Software Heritage in research articles, journals, and books
+      + [[https://www.softwareheritage.org/swhap/][rescue and preserve landmark legacy source code]] with SWHAP
+#+BEAMER: \pause
+*** Engage with Software Heritage as an individual
+    - join the [[https://www.softwareheritage.org/ambassadors/][ambassador program]], help raise awareness
+    - contribute to technical and scientific development
+#+BEAMER: \pause
+*** Engage with Software Heritage as an organization
+    - become [[https://www.softwareheritage.org/support/sponsors/][a member/sponsor]]
+    - build a Software Heritage mirror (like ENEA is doing)
+    - contribute to the preservation mission
+** Thank you!
+   #+latex:    \centering{\huge\bf Questions?}
+  \vspace{-.5em}
+*** Resources
+  - newsletter :: https://www.softwareheritage.org/newsletter/
+  - blog :: https://www.softwareheritage.org/blog/
+  - archive :: https://archive.softwareheritage.org/
+  - media, press, etc. :: https://annex.softwareheritage.org/
+
+*** References (see https://www.softwareheritage.org/publications)
+  #+BEGIN_EXPORT latex
+  \begin{thebibliography}{Foo Bar, 1969}
+  \footnotesize
+%  \bibitem{SwForumEu2021} R. Di Cosmo, \emph{A revolutionary infrastructure for Open Source}, 2021, EU Software Forum \href{https://annex.softwareheritage.org/public/talks/2021/2021-03-24-SwForum.pdf}{(slides)} \href{https://youtu.be/AwY527kDMfM?t=178}{(video)}
+  \bibitem{EOSCSirs2020} EOSC SIRS Task Force, \emph{Scholarly Infrastructures for Research Software}
+  \newblock 2020, European Commission, \href{https://doi.org/10.2777/28598}{(10.2777/28598)}
+  \bibitem{DiCosmo2020d} R. Di Cosmo, \emph{Archiving and Referencing Source Code with Software Heritage}
+  \newblock ICMS 2020 \href{https://dx.doi.org/10.1007/978-3-030-52200-1_36}{(10.1007/978-3-030-52200-1\_36)}
+%  \bibitem{DiCosmo2019} R. Di Cosmo, M. Gruenpeter, S. Zacchiroli\newblock
+%  \emph{Referencing Source Code Artifacts: a Separate Concern in Software Citation},\newblock
+%  CiSE 2020 \href{https://dx.doi.org/10.1109/MCSE.2019.2963148}{(10.1109/MCSE.2019.2963148)}
+%  \href{https://hal.archives-ouvertes.fr/hal-02446202}{(hal-02446202)}
+%  \bibitem{alliez:hal-02135891} P. Alliez, R. Di Cosmo, B. Guedj, A. Girault, M.-S. Hacid, A. Legrand and N. Rougier\newblock
+%  \emph{Attributing and referencing (research) software: Best practices and outlook from Inria}, \newblock
+%  CiSE 2020 \href{https://doi.ieeecomputersociety.org/10.1109/MCSE.2019.2949413}{(10.1109/MCSE.2019.2949413)}
+%  \href{https://hal.archives-ouvertes.fr/hal-02135891}{(hal-02135891)}
+  \bibitem{Abramatic2018} J.F. Abramatic, R. Di Cosmo, S. Zacchiroli,
+  \emph{Building the Universal Archive of Source Code}, 
+  \newblock CACM, October 2018 \href{https://doi.org/10.1145/3183558}{(10.1145/3183558)}
+  \end{thebibliography}
+  #+END_EXPORT
+* Appendix                                                       :B_appendix:
+  :PROPERTIES:
+  :BEAMER_env: appendix
+  :END:
+** 
+   \vfill
+   \centerline{\Huge Appendix}
+   \vfill
+* Revolutionary infrastructure, scientific challenges
+** A revolutionary infrastructure /designed for software source code/
+#+INCLUDE: "../../common/modules/swh-as-infrastructure.org::#oneslide" :only-contents t :minlevel 3
+** A challenging scientific and technical undertaking
+*** A novel, large infrastructure
+    - object storage [[https://www.softwareheritage.org/2021/03/11/towards-a-next-generation-object-storage-for-software-heritage/][with peculiar workload]]
+    - gigantic Merkle graph
+    - counting tens of billions of objects ([[https://www.softwareheritage.org/2021/05/11/next-generation-counters/][reuse P. Flajolet's seminal work]])
+    - and much more: see [[https://www.softwareheritage.org/2021/04/08/swh-2021-technical-roadmap/][the 2021 technical roadmap]]
+#+BEAMER: \pause      
+*** First datasets are available for Big Code analysis
+   - full graph of software development (~20Bn nodes, ~200Bn edges)
+     see Pietri, Spinellis, Zacchiroli, MSR 2019 https://dx.doi.org/10.1109/MSR.2019.00030
+   - MSR 2020 mining competition
+     see https://2020.msrconf.org/track/msr-2020-mining-challenge#Call-for-Papers
+* All the source code   
+** All the source code!
+   #+BEAMER: \begin{center}\includegraphics[width=\extblockscale{\linewidth}]{swh-collect-axes}\end{center}
+** All the source: strategies
+   #+BEAMER: \begin{center}\includegraphics[width=\extblockscale{\linewidth}]{swh-collect-strategies}\end{center}
+* Milestones, policy
+** Milestones                                                       :B_block:
+   #+INCLUDE: "../../common/modules/swh-key-dates.org::#keydates" :minlevel 3 :only-contents t
+** Policy highlight: the EU Copyright reform\hfill adopted March 28 2019
+*** "Upload filters": a threat to /all modern software development/
+    - developing platforms (GitHub, GitLab, Bitbucket, etc.)
+    - *distribution platforms (Maven, Pypi, CRAN, CTAN, etc.)*
+    - *archives (Software Heritage)*
+#+BEAMER: \pause
+*** We got an exclusion for
+    \hfill /\sout{non for profit} open source software developing *and sharing* platforms/
+#+BEAMER: \pause
+*** Key role of Software Heritage
+    \hfill policy-maker awareness, essential insights for NGOs, government contacts
+* SWHIDs by the example                                            :noexport:
+** A word on the trust model for systems of identifiers
+   \vspace{-5pt}
+*** Two general classes of systems of identifiers
+    - intrinsic :: /computed/ from the object /(no registry required, fully decentralised)/\\
+      /(e.g.: chemical notation, music notation, hashes, SWHIDs)/\pause
+    - extrinsic :: /assigned/ by an authority /(need a registry)/\\
+      /(e.g.: passport number, DOI, ARK, RRID, etc.)/\pause
+    \mbox{}\hfill See [[https://www.softwareheritage.org/2020/07/09/intrinsic-vs-extrinsic-identifiers/][the dedicated blog post]] for more details 
+#+BEAMER: \pause
+*** Trust model, extrinsic (e.g. DOIs)                              :B_block:
+    :PROPERTIES:
+    :BEAMER_COL: .5
+    :BEAMER_env: block
+    :END:
+#+ATTR_LATEX: :width \linewidth
+file:doi-vs-pid-1.pdf
+#+BEAMER: \pause
+*** Trust model, intrinsic (e.g. SWHIDs)                            :B_block:
+    :PROPERTIES:
+    :BEAMER_env: block
+    :BEAMER_COL: .45
+    :END:
+#+ATTR_LATEX: :width .8\linewidth
+file:doi-vs-pid-3.pdf
+*** Trust model for DOIs with checksums                    :B_block:noexport:
+    :PROPERTIES:
+    :BEAMER_COL: .5
+    :BEAMER_env: block
+    :END:
+#+ATTR_LATEX: :width \linewidth
+file:doi-vs-pid-2.pdf
+***                                                :B_ignoreheading:noexport:
+    :PROPERTIES:
+    :BEAMER_env: ignoreheading
+    :END:
+** A worked example
+    #+LATEX: \centering\forcebeamerstart
+    #+LATEX: \only<1>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/merkle_1.pdf}}}
+    #+LATEX: \only<2>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/contents.pdf}}}
+    #+LATEX: \only<3>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/merkle_2_contents.pdf}}}
+    #+LATEX: \only<4>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/directories.pdf}}}
+    #+LATEX: \only<5>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/merkle_3_directories.pdf}}}
+    #+LATEX: \only<6>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/revisions.pdf}}}
+    #+LATEX: \only<7>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/merkle_4_revisions.pdf}}}
+    #+LATEX: \only<8>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/releases.pdf}}}
+    #+LATEX: \only<9>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/merkle_5_releases.pdf}}}
+    #+LATEX: \only<10>{\colorbox{white}{\includegraphics[width=\extblockscale{\linewidth}]{git-merkle/snapshots.pdf}}}
+    #+LATEX: \forcebeamerend
+* Big code                                                         :noexport:
+** Software Heritage for Research and Innovation
+*** Reference platform for /Big Code/                            :B_picblock:
+    :PROPERTIES:
+    :BEAMER_opt: pic=universal, leftpic=true, width=.2\linewidth
+    :BEAMER_env: picblock
+    :BEAMER_act:
+    :END:
+   - unique *observatory* of all software development 
+   - *big data, machine learning* paradise: classification, trends, coding patterns, code completion...
+#+BEAMER: \pause
+*** First datasets are available!
+   - full graph of software development (~20Bn nodes, ~200Bn edges)
+     see Pietri, Spinellis, Zacchiroli, MSR 2019 https://dx.doi.org/10.1109/MSR.2019.00030
+   - MSR 2020 mining competition
+     see https://2020.msrconf.org/track/msr-2020-mining-challenge#Call-for-Papers
+
+* Public code, mirrors                                              :B_block:
+** News : archiving /public/ code
+   #+latex: \begin{center}
+   #+ATTR_LATEX: :width 0.7\linewidth
+   file:codeetalab.png
+   #+latex: \end{center}
+#+BEAMER: \pause
+   https://code.etalab.gouv.fr
+** News : ENEA mirror
+*** Thomas Jefferson, February 18, 1791 :B_block:
+    :PROPERTIES:
+    :BEAMER_ACT:
+    :BEAMER_env: block
+    :END:      
+#+latex:  {\em
+  ...let us save what remains: not by vaults and locks which fence them
+  from the public eye and use in consigning them to the waste of time,
+  but by such a multiplication of copies, as shall place them beyond
+  the reach of accident.
+#+latex: }
+   #+BEAMER: \pause
+*** Welcoming ENEA                                                  :B_block:
+    :PROPERTIES:
+    :BEAMER_env: picblock
+    :BEAMER_OPT: pic=LogoENEAcompletoENG.png, leftpic=true, width=.7\linewidth
+    :END:
+     - first *institutional* mirror
+     - increased resilience
+     - *AI infrastructure* for researchers
+     - stepping stone to \endgraf
+       \hfill an European joint effort
diff --git a/talks-public/2021-09-15-EcolePonts/Makefile b/talks-public/2021-09-15-EcolePonts/Makefile
new file mode 100644
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@@ -0,0 +1 @@
+include ../Makefile.slides