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Going from Python to Guile Scheme - a natural progression

py2guile book

Python is the first language I loved. I dreamt in Python, I planned in Python, I thought I would never need anything else.

 - Ebook: 0.01 ฿
   pdf, epub and mobi
 - Softcover: 14.95 €
   with digital companion
 - Source: download
   free licensed under GPL

follow the blue rabbit

========= blue-rabbit =========
follow the blue rabbit
through the looking glass
to find your real self
========= looking glass =========

Australia gets mandatory data retention

Australia gets mandatory data retention — with unchecked access by roughly any local or federal police agency and “Any other agency the Attorney General publicly declares”. (So much for separation of powers)

And they can use that in court.

→ » Australia: Now is the time to go dark « ←

Dear Australians: This is what we have been talking about the past 10 years. The tech for confidential communication might still be cumbersome to use, but you now need it.

If you want to use Freenet for that, I’ll gladly help you set it up.

IPCC bibtex entries

I repeatedly stumbled over needing bibtex entries for the IPCC reports. So I guess, others might stumble over that, too. Here I share my bibtex entries for some parts of the IPCC reports.1

IPCC 1990 WG1 (physical science basis)

  title = {Climate Change 1990 The Science of Climate Change},
  publisher = {The Intergovernmental Panel on Climate Change},
  year = {1996},
  editor = {J.T. Houghton and G.J. Jenkins and J.J. Ephraums},
  author = {IPCC Working Group I}

  1. In IPCC 2013 WG1 they finally provide bibtex in their zip of references, but without item headers — you can’t use these directly. 

Freenet as backing store for sites on the clearnet (in use today)

Chris Double (bluishcoder) changed his main website to be served directly from Freenet:

Thanks to this, the same article is now available from my inproxy.

And, naturally, from Freenet:


Using Guile Scheme Wisp for low ceremony embedded languages

Programming languages allow expressing ideas in non-ambiguous ways. Let’s do a play.

say Yes, I do!
Yes, I do!

Information challenges for scientific publishing

On 2015-08-27, Researchers from the Reproducibility Project: Psychology reported that in 100 reproduction studies, only “47% of original effect sizes were in the 95% confidence interval of the replication effect size” (RPP SCIENCE 2015, an overview of the results is available in Scientific American; in german from DLF Forschung Aktuell).

I take this worrying result as cue to describe current challenges to scientific publishing and measures to address them — including reproduction experiments, and what to do if they contest previously published and referenced work.


PDF (to print)

Org (source)

Scientific publishing has come a long way since it’s beginning, and it’s principles have allowed it to scale up from a few hundred active scientists worldwide to conferences with tens of thousands of people for a given topic. But in the last few years it hit its limits. It becomes harder each year to keep up with the amount of new papers being published and even scientists from similar fields repeatedly reinvent the same methods. To scale further and to continue to connect the scientific community, it must adapt to make it easier to get an understanding of the current state of science and keep up to date with new findings.

To grow from these challenges, scientific publishing needs to

„Kein Shitstorm kann jemals so schlimm sein wie der Applaus von Leuten, die auch klatschen, wenn ein Flüchtlingsboot mit 800 Menschen im Mittelmeer versinkt“

Ich habe Circus HalliGalli immer ignoriert, weil mich der Stil genervt hat. Aber hier ziehen sie die Rote Linie klarer als irgendwer anders, den ich bisher dazu gehört habe:

„Keine Fernsehquote, kein Shitstorm kann jemals so schlimm sein wie der Applaus von Leuten, die auch dann laut klatschen, wenn ein Flüchtlingsboot mit 800 Menschen im Mittelmeer versinkt.“

Freenet Communication Primitives: Part 2, Service Discovery and Communication

Basic building blocks for communication in Freenet.

This is a guide to using Freenet as backend for communication solutions - suitable for anything from filesharing over chat up to decentrally hosted game content like level-data. It uses the Python interface to Freenet for its examples.

Mirror, Freenet Project, Arne Babenhauserheide, GPL
Freenet Project,
License: GPL.

This guide consists of several installments: Part 1 is about exchanging data, Part 2 is about confidential communication and finding people and services without drowning in spam and Part 3 ties it all together by harnessing existing plugins which already include all the hard work which distinguishes a quick hack from a real-world system.

Note: You need the current release of pyFreenet for the examples in this article (0.3.2). Get it from PyPI:

# with setuptools
easy_install --user pyFreenet
# or pip
pip install --user --egg pyFreenet

This is part 2: Service Discovery and Communication. It shows how to find new people, build secure communication channels and create community forums. Back when I contributed to Gnutella, this was the holy grail of many p2p researchers (I still remember the service discovery papers). Here we’ll build it in 300 lines of Python.

Welcome to Freenet, where no one can watch you read!

Lohnsenkung im öffentlichen Dienst wegen leerer Kassen?

→ Antwort zum Kommentar „Leidtragenden des Streiks sind … die normalen Bürger“ zu ausgelaugte Gewerkschaft in der Taz.

Die öffentlichen Arbeitgeber schwimmen nicht im Geld, weil die Regierenden es nicht wagen, die Einnahmenseite zu erhöhen. Bei immer weiter steigenden Konzerngewinnen wird es Zeit, dass sich das ändert.

Arbeitslosengeld als „Erstattung“…

→ Kommentar zum Kommentar „kriegen Leute mit ALG2 … "erstattet"“ in der Taz.

ALG2 ist keine Erstattung. Es ist eine grundgesetzlich garantierte Sicherung des Existenzminimums.

Hintergrund sind Artikel 1, GG: Die Würde des Menschen ist unantastbar und Artikel 2, GG: Das Recht auf Leben und körperliche Unversehrtheit.

Nobelpreis Physik 1993: Doppelpulsar belegt Gravitationswellen, Hulse und Taylor

1993 haben Russell A. Hulse und Joseph H. Taylor Jr. den Nobelpreis in Physik für die Entdeckung des Doppelpulsarsystems PSR1913+16 erhalten.

Anhand des Systems aus zwei Pulsaren konnten sie belegen, dass es Gravitationswellen gibt (was auch ein weiterer Beweis dafür ist, dass es sinnvoll ist, den Himmel zu beobachten, um die Welt zu verstehen ☺).

Advertisers threatened me on twitter for ridiculing their misleading ad



  2016: Hackers can now steal the #slowblood scanning biometric data from Android phones.

colortext: hackers

Today advertisers answered a tweet with a link to a story about the possibility to steal fingerprints remotely from Android phones with a blatant advertisement for their “superior” “proprietary” technology. When I ridiculed their advertisement, they threatened me. Let’s call them colortext and their brand #slowblood.12

  1. I will not name them here because they later threatened me with a trademark violation. The name is in the pictures because I’m pretty sure that if they use their brand as hashtag, the hashtag is fair game on twitter. In this text I’ll instead use the names colortext for the company and and #slowblood for the tech. 

  2. I don’t have anything against their tech. It might be brilliant and provide security for years to come, or it might just be another fad. Their way to advertise it as the solution to all the security problems is what irks me. It’s still a marker which is tied to your body, so you cannot change it in case it is copied. As such, its security properties are questionable: If it is copied once, you as person cannot use the method again until there are new sensors which cannot be fooled by copies of data from the old sensors. For its security properties you have to rely on constant improvements in the sensors -- but this offers no advantage over copied fingerprints from the android. The only advantage I can see is that you can’t steal these prints in real-life resolution by handing someone a glass water. You might now think that they actually had a point, but sadly that security property is completely irrelevant to the article on which the advertisers replied, because the article showed that fingerprints where copied in the resolution measured by the sensor. There would be no advantage at all from switching from fingerprint to #slowblood, so what they did is just bad advertising -- and sending out threats when they were called out for their bad style. 

Surface Area of regions on an ellipsoid Earth


PDF (to print)

Org (source)

Data (netCDF4)

Calculating the area of arbitrary regions on the Earth approximated as an ellipsoid. I needed this for conversion between the output of different models.

It’s calculated in Emacs Lisp, which showed me that for somewhat complex mathematical tasks Lisp syntax isn’t only unproblematic, but actually helps avoiding mistakes. And full unicode support is great for implementing algorithms with ω, λ and φ.


My server was breached - sorry for the downtime

After 4 weeks of downtime my sites are online again.

Freenet Communication Primitives: Part 1, Files and Sites

Basic building blocks for communication in Freenet.

This is a guide to using Freenet as backend for communication solutions - suitable for anything from filesharing over chat up to decentrally hosted game content like level-data. It uses the Python interface to Freenet for its examples.

TheTim from Tim Moore, licensed under cc by
from Tim Moore,
License: cc by.

This guide consists of several installments: Part 1 (this text) is about exchanging data, Part 2 is about confidential communication and finding people and services without drowning in spam and Part 3 ties it all together by harnessing existing plugins which already include all the hard work which distinguishes a quick hack from a real-world system. Happy Hacking and welcome to Freenet, the forgotten cypherpunk paradise where no one can watch you read!

IT des Deutschen Bundestages fremdkontrolliert. Oppositionsabgeordnete ratlos.

Diese Aussage trifft gerade die Grünen-AbgeordneteTabea Rößner in der FAZ. Ich wollte das nur auf G+ weitergeben, als mich meine eigenen Worte wie ein Schlag getroffen haben:

IT des Deutschen Bundestages fremdkontrolliert. Oppositionsabgeordnete ratlos.

Verdammt, in welcher Welt leben wir? Ist das ein Agententhriller oder düstere Science Fiction? So eine Titelzeile würde in Star Wars passen, als Zeitungsmeldung während der Imperator den Senat übernimmt.

concise commit messages

Written in the discussion about a pull request for Freenet.

When I look up a commit, I’m not searching for prose. I’m searching for short snippets of information I need. If they are long-winded explanations, I am unlikely to even read them.

To understand this, please imagine coming back home, getting off the bike and taking 15 minutes to look at the most recent pull-request. You know that you’ll need to start making dinner at 19:00, so there is no time to waste.

Vortrag: SUMA-Award für das Freenet-Projekt (Video)

Mein Vortrag beginnt bei 5:56.

Transkript / Untertitel

Ich bin dabei, den Text zu transkribieren, aber es wird noch etwas dauern, bis ich fertig bin. Sobald ich fertig bin, gibt es das als Untertitel-Datei. Was ich bisher habe als Text:

Mit Freenet sicher kommunizieren

Kannst du in wenigen Worten beschreiben, warum mit Freenet sicher zu kommunizieren ist?
— Falk Flak

Bei Freenet gibt es zwei Arten sicher zu kommunizieren:

  1. Du kannst dir ein Pseudonym erschaffen, unter dem du in Freenet-Internen Foren schreiben und anderen Nutzern anonyme, aber spamgeschützte E-Mails schreiben kannst. Die Daten werden dafür direkt zwischen Freenet Nutzenden über mehrere Schritte ausgetauscht, es gibt also keinen zentral kontrollierten Server. Du kannst Daten hochladen, die auch dann noch verfügbar sind, wenn du offline bist, aber nur für diejenigen, denen du den Link dazu gegeben hast.

  2. Du verbindest dich direkt mit Freunden. Von außen kann sichtbar sein, dass ihr euch kennt, aber nicht wann und über was ihr redet. Die Daten, die Freenet für den Normalbetrieb austauscht, sehen genauso aus wie Kommunikation zwischen dir und deinen Freunden, verdecken sie also.

Eine kurze Präsentation dazu: Freenet Nutzen: Technische Lösungen für freie Kommunikation im Internet

Hitchhikers Guide on Towels - Read from Space

Samantha Cristoforetti reads the Hitchhikers Guide to the Galaxy on the International Space Station

This is the world we live in: The Hitchhikers Guide read from Space.

If you don’t get goosebumps just thinking about it, envision it again: The old visions are becoming real step by step, and now those who actually venture in space read the works of visionaries from their temporary home beyond the atmosphere.

New traditions form from a reality which still seems

Secure communication with GnuPG and E-Mail

How E-Mail with GnuPG could hide when you talk, where you talk from and what you talk about.

or in technical terms:

E-Mail with perfect forward security, hidden subject and masked date using GnuPG and better frontends.

If you regularly read my articles, you’ll know that I’m a proponent of connecting over Freenet to regain confidential and pseudonymous communication.

Here I want to show how it would be possible to use E-Mail with GnuPG to get close to the confidentiality of Freenet friend-to-friend communication, because we have the tech (among the most heavily scrutinized and well-tested technology we use today) and we have the infrastructure. All it requires are more intelligent E-Mail clients. Better UI which makes the right thing easy.

Wir passen aufeinander auf (Menschen sind toll!)

Ich bin heute früh mit dem Rad zum Finanzamt, um die Steuererklärung abzugeben, und dann weiter zur Arbeit. Nach gut 15 km Fahrt wurde ich müde und entschied, eine Pause zu machen. Die Sonne schien und die Luft war angenehm kühl also legte ich meine Jacke hinter das Rad, hängte den Helm an den Lenker und legte mich auf den Radweg neben der Straße.

Nach zwei Minuten hörte ich einen Radler. Er fragte mich mit Osteuropäischem Akzent: „Ist alles OK?“. Ich antwortete „Alles OK, ich mache nur Pause.

Euch trifft der Bahnstreik? Dann lest die Streikzeitung!

Gestern habe ich versucht, herauszufinden, was die GDL im Streik eigentlich will. Auf ihrer Seite gibt es dazu wenig Infos und normale Zeitungen haben sich als nutzlos erwiesen.

Sinnvolle Informationen habe ich erst in der Streikzeitung bekommen - die ich euch hiermit wärmstens ans Herz legen möchte:

Streikzeitung 2015-05 (PDF)

Real Life Infocalypse

Freenet Logo: Follow the Rabbit DVCS in the Darknet. The decentralized p2p code repository.

In this guide I show by example how you can use the Infocalypse plugin for distributed development without central point of failure or reliance on unfree tools.12

If you think “I have no idea what this tool is for” (like this reddit commenter): Infocalypse gives you fully decentralized Github with real anonymity, using only free software.

# freenet -> local
hg clone freenet://ArneBab/life-repo
# local -> freenet
hg clone life-repo real-life
hg clone real-life freenet://ArneBab/real-life
# send pull request
cd real-life
hg fn-pull-request --wot ArneBab/life-repo
# check for pull-requests
cd ../life-repo
hg fn-check-notifications --wot ArneBab

If you like this, please don’t only click like or +1, but share it with everyone who could be interested. The one who knows best how to reach your friends is you — and that’s how it should be.

  1. This guide shows the convenient way of working which has a higher barrier of entry. It uses WoT Pseudonyms to allow you to insert repositories by Pseudonym and repository name. If you can cope with inserting by private key and sending pull-requests manually, you can use it without the WoT, too, which reduces the setup effort quite a bit. Just skip the setup of the Web of Trust and Freemail and plugins. You can then clone the life repo via hg clone freenet://USK@6~ZDYdvAgMoUfG6M5Kwi7SQqyS-gTcyFeaNN1Pf3FvY,OSOT4OEeg4xyYnwcGECZUX6~lnmYrZsz05Km7G7bvOQ,AQACAAE/life-repo.R1/4 life-repo. See hg fn-genkey and hg help infocalypse for details. 

  2. Infocalypse shows one of many really interesting possibilities offered by Freenet. To get a feeling of how much more is possible, have a look at The Forgotten Cryptopunk Paradise

Strong Kerrigan

When you win Starcraft 2 Heart of the Swarm in brutal difficulty without losing Kerrigan even once, you get an ending with a truly strong Kerrigan.234

Clearly you are my greatest failure. Now at long last, you will die.

Again Mengsk activates the Xel'Naga artifact. As the lightning from the artifact tears at her flesh and cracks every part of her body, Kerrigan rasps an answer:

  1. The epub icon was created by the Oxygen Team ( and is licensed under the GNU LGPL

  2. This is what I’d have wished to see. 

  3. All characters in this story belong to Blizzard. I also published this story in the Starcraft forums

  4. The one thing I resent about Kerrigan in Starcraft 2 is that they made her weak.

    In SC1 Kerrigan embraced and ruled the swarm. She started as strong terran, never to let anyone talk down to her, never afraid to say what she wanted. Then she got infested, and she prevailed over the infestation, becoming the queen of blades, ruling the Zerg instead of being ruled by the Overmind.

    In the cutscenes of SC2 she’s a helpless wreck, ever reliant upon the help of others and exposed as a tool of the overmind to free the swarm from Amon.

    It feels as if someone wrote the story to deconstruct the legend of the queen of blades. The in-game story seems much better, though. 

Mein erstes Papier: Carbontracker und TM5-4DVar

Mein erstes Papier ist seit dem 25. März 2015 in Interaktiver Diskussion:

Comparing the CarbonTracker and TM5-4DVar data assimilation systems for CO₂ surface flux inversions
— A. Babenhauserheide, S. Basu, S. Houweling, W. Peters and A. Butz

Modellierte Biosphären-Senke für Kohlenstoff in Nord-Amerika April 2009 bis April 2010 mit zwei Modellen und steigender Dichte an Beobachtungsstationen. Zum Vergleich: Die Jährliche Kohlenstoff-Quelle durch Verbrennung von Öl und Kohle beträgt etwa 10 PgC.

power and deception

A religious leader is nothing more than a media-star who managed to convince people that the tale, in which he or she is special, is actually true.

Just like aristocrats managed to convince people, that what their ancestors did, gives them the right to control the lives of other people.

Simple daemon with start-stop-daemon and runit


PDF (to print)

Org (source)

Creating a daemon with almost zero effort.

Zeitungen exklusiv bei Facebook - Idiotie ohne Ende

→ Kommentar zum Artikel Rettet uns Facebook? (Journalismus in Online-Netzwerken), in dem Daniel Kretschmar in der Taz die These aufstellt, es sei wegen dem Versagen der Verlage, digital Geld zu verdienen, zu begrüßen, wenn bei exklusivem Vertrieb über Facebook „am Ende ein paar Brotsamen für die Inhalteproduzenten abfallen mögen“.

Was machen die Zeitungsverlage, wenn Facebook selbst Journalisten einstellt - so wie Amazon zum Buchhändler wurde?

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