“Shoot ALL the Hackers!”

One of the long-running photography projects by Dennis van Zuijlekom (Hackerspace Hack42, Arnhem).
Its focus is portrait photography of persons who relate themselves to hacker/maker culture.
Dennis started this project in 2015 and it’ll never be truly finished, as there will always be new
hackers to photograph, as well as old friends having new faces.

Dennis takes great pride in photographing people looking at their very best and the results speak for themselves.
He’ll invite you to have your headshot taken during this event (and/or sometime afterwards).
You’ll be using his photo in your personal bio, guaranteed. The project and the photos are licensed Creative Commons,
CC-BY-SA, as Open Source and free/libre content is important to Dennis.



About Dennis:
Dennis van Zuijlekom (1979), is a Linux/UNIX sysadmin and one of his
many hobbies is photography. His works can be found both all over the
online and in the offline world. He has broad interests, but really
likes doing portrait photography. He has been a member of Hackerspace
Hack42 Arnhem since 2011 and has been a board-member since 2018. He is
usually known as ‘dvanzuijlekom’ on IRC and in various online media. He
was also a mindless jerk and the first against the wall when the
revolution came.


Blacksmith Workshop (SparkShack @ HackerHotel) – Gori

Blacksmiths are the original proto-hackers: makers of tools and machines, enablers of civilization. The craft has been around for at least 7000 years, and it is still going strong. This year at hacker hotel, you will have the chance to try it out for yourself! SparkShack, the metal workshop located at RevSpace in The Hague will be present, with an array of materials and tools, providing demonstrations and workshops on steel forging and aluminium casting. If there is interest and we all feel like it, we wil do more advanced things, like pattern-welding steel to make damascus, etching and staining steel, forging aluminium or casting copper and bronze.

The following activities are planned :

  • Forging and casting demos! Times will be announced at the event.
  • Ask Gori for a introduction to forging workshop. It takes about 1 hour, two persons max. Times are random and flexible
  • Have your custom 3D printed design cast in metal! Contact beforehand if you want to do this.
  • Come and play with us anytime the workshop is open!

Most important thing is that if you want to play at the SparkShack, please bring protective clothing. Red hot steel and molten aluminum are very dangerous and can seriously hurt you!
This means :

  • Closed leather shoes
  • Safety overall or jeans and thick cotton shirt
  • Safety glasses
  • Leather gloves
  • Ear protection

Absolutely no synthetic clothing! Synthetics can catch fire and will melt onto your skin!

SparkShack @ HackerHotel is organized by Gori, a scientist and dad by day, hacker and blacksmith at night.

Impressioning Workshop – Jan Willem Markus

Impressioning is the art of filing a key to a unknown lock. Impressioning is closely related to lockpicking where the goal is to open the lock. With impressioning you can save your progress half way and have a working key in the end.

How does it work? By inserting a brass key blank (uncut key) into the lock and apply rotational force and up/down movement you damage the key (and lock) slightly. The damage to the key is useful as these are the places where the pins are binding in the lock and we can file these binding pin positions down.

After repeating these steps, we’ll have a working key. This usually takes between 15 to 30 minutes with practice. The participants will need about an 30 to 60 minutes to create a working key. By ‘cheating’ we can increase the chance of success, and lower the time needed.

We impression on Abus C83 locks as this is the lock I practice on. This lock is used in the European impressioning championships. I’ve got all the materials for this workshop, and can teach 5 people at once. Even more when tools are shared. No further equipment is required.

In preparation I suggest watching one of Jos Weyers’s talks on Impressioning (

About Jan Willem:

My name is Jan-Willem Markus (@jwrm22), I’m an electronics engineer by trade. I’m always in for a challenge. I found my way in to the hacker community by BEEA ( and SHA2017. I’m a member of Toool and BitLair.

This is a chance for me to improve upon my teaching skills and make impressioning more popular. I’ll bring my lockpicks with me too, and some stupid easy locks.

Blij met Bleek:

T-shirts decoreren met bleek is gaaf en niet moeilijk. We gaan sjablonen
maken van stickerpapier of dun karton; als je voorzichtig snijdt of
knipt krijg je een positieve en een negatieve mal, die kun je allebei
gebruiken en het effect is heel verschillend.

Ook heel gaaf: tie&dye-achtige technieken kunnen ook met bleek. Zo maak
je spiraalnevels, bliksemschichten, tijgerstrepen of nog iets heel
anders. Je kunt dit ook doen met een bedrukt shirt: de opdruk blijft
gewoon staan.

Welke kleur je precies krijgt, is lastig te voorspellen, maar dat is een
deel van de lol. Het is hoe dan ook een beetje een eigenzinnige en
onvoorspelbare techniek; het resultaat is in ieder geval niet saai en
het gaat er nooit, maar dan ook nooit meer uit.

– T-shirts in (donkere) kleuren naar keuze. Hoeven niet nieuw te zijn.
Plunder bijvoorbeeld de kringloopwinkel of je kast.
– Simpele logo’s, plaatjes of teksten die je op je shirt wilt hebben.
Maak het niet te subtiel. Alleen een idee is ook goed, dat werken we dan
ter plekke wel uit.
– Als je een gevoelige huid hebt, breng dan afwashandschoenen mee om te
dragen tijdens het uitspoelen van je shirts.

English Summary
In this workshop, we will be making boring T-shirts into interesting,
unique and cool T-shirts, using bleach and various techniques. Please
bring your own boring T-shirts in darker colours; prints are OK and will
remain in place. If you want to use existing (simple) designs and
(simple) logos, print them on thick paper or thin cardboard and, you
guessed it, bring them.


What the Helmet:

Engelstalige samenvatting:
Life is dangerous, protect yourself! But do it in style. This workshop
will teach you how to change a normal, boring hard hat / builder’s
helmet into a super cool, metal like cyberpunk helmet. It can look like
rusty iron, pewter, bronze or copper and it can have letters or logos of
your own design. Your friends will envy you and wonder how you suddenly
got so cool and crafty.
The workshop consists of two parts: in the first, we prepare the helmet
for painting, add faux welding seams, rivets, and other 3D decorations.
Then we paint it. In the second part, we add the metal look for extra
shinies. If you want to use weird objects, electronics or gears… bring
There is a 5 € fee for materials, which covers the helmet itself and
everything else.

An introduction to Open Source Intelligence ( OSINT ) – Onno

Open Source Intelligence is more than search engines such as “Google“ and Internet.
Examples of resources are Job announcements, public records (eg building permits), personal
records, news, periodical (press releases, radio, television) Web-pages, Blogs, Chatroom’s,
forums, file sharing, company information (eg. whois), online News.
We all know that loose lips sink ships.
Open Source Information is a constant threat to any organization, mission and yourself.
Collecting information from available public, or open-sources is done by
army, security, law, spies, Red Team’s, business functions and now you.

The workshop is open for everyone with a small hands-on training.
Because it is on Sunday we will start slow.
After a brief introduction about OSINT we start information gathering.
We will use case’s from last year to find out how Open Source Intelligence is used in
spearfishing attacks.
The presentation is done many in English, if you only speak German or Dutch that is no
Students need:
Computer with a “”Virtual Machine” of there choice installed and enough ram and disk space.
(Tablets, Arm mini computers are perhaps not a good idea for beginners)
Kali Linux disto with a free Maltego community registration or Maltego community edition
installed on your OS. Kali Linux is preferred because more tools are installed.

About Onno:
Looking for a new adventure.
Illustrator with interest in puzzling, CTF, soldering, hardware, Social engineering, books, Threat
Intelligence, Open Source Information and much more.
Drinks Tea.  Everything about me is true…….

Give a workshop!

Participants of Hacker Hotel give lectures and workshops in all kinds of disciplines and levels.

There is more than enough space to give your prepared or unprepared workshops.
We have 10 different rooms, varying from secret lairs to big presentation rooms.
Giving a workshop, whatever the skill level, is greatly appreciated. Contact us!