2.0 -//Pentabarf//Schedule//EN PUBLISH Z9FEAG@@pretalx.riat.at -Z9FEAG Intro to the Critical Decentralization Cluster en en 20251227T110000 20251227T111000 0.01000 Intro to the Critical Decentralization Cluster PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/Z9FEAG/ CDC Triangle Diego Salazar PUBLISH TJXALG@@pretalx.riat.at -TJXALG The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3 en en 20251227T111000 20251227T115000 0.04000 The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3 PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/TJXALG/ CDC Triangle dllud Pavel Polach bobotronic PUBLISH FGHX77@@pretalx.riat.at -FGHX77 OpenPGP 2025: Zero → Hero en en 20251227T120000 20251227T140000 2.00000 OpenPGP 2025: Zero → Hero PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/FGHX77/ CDC Triangle darko PUBLISH ZPV3UT@@pretalx.riat.at -ZPV3UT What’s Next with Open Hardware at FOSSASIA and Beyond en en 20251227T140000 20251227T143000 0.03000 What’s Next with Open Hardware at FOSSASIA and Beyond In 2025, teams at FOSSASIA initiated several open hardware projects developed entirely from the ground up, including a new ARM based Pocket Science Lab, an updated LED Badge platform, and an NFC powered ePaper badge enabling energy independent content transfer. However, this session goes beyond a project update. It situates these developments within a wider global movement of open hardware initiatives across Asia, Europe, and other regions. Drawing on experiences from FOSSASIA as well as broader perspectives from the international open hardware community, the talk examines where open hardware is heading as a decentralised, collaborative practice. With input from international experts and community contributors, the session will explore trends emerging, including evolving manufacturing models, open silicon and firmware stacks, supply chain resilience, and the realities of sustaining openness at scale. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ZPV3UT/ CDC Triangle Mario Behling PUBLISH MMHXLC@@pretalx.riat.at -MMHXLC SeedSigner DIY Bitcoin signing device build workshop en en 20251227T143000 20251227T163000 2.00000 SeedSigner DIY Bitcoin signing device build workshop Seedsigners are open-source DIY signing devices which can be built using "normal" hardware like a Raspberry Pi and act as kind of hardware wallets to sign Bitcoin transactions. Since the hardware is missing a secure element chip, the keys are saved externally, usually via self-drawn QR-codes which are read again for every use via the build-in camera. We brought a few kits with us which we sell for 45€ and build together. We will solder the 40pin GPIO header to the Raspberry Pi Zero, flashing the firmware on the MicroSD card and then build everything together in the 3d-printed enclosure. The kit includes: Raspberry Pi Zero 1.3 (without Wifi or Bluetooth chip), GPIO-header to solder Display-Hat with joystick and buttons Camera 64GB MicroSD card MicroUSB to USB-C cable 3D printed enclosure 6 printed templates for self-drawn QR-Codes PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/MMHXLC/ CDC Triangle freerk PUBLISH SZWNVV@@pretalx.riat.at -SZWNVV Software Liberation Toolbox Exchange en en 20251227T163000 20251227T173000 1.00000 Software Liberation Toolbox Exchange PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/SZWNVV/ CDC Triangle Zebra PUBLISH ENXTHG@@pretalx.riat.at -ENXTHG Update 2025. Digital integrity of the human person, A new fundamental right. en en 20251227T173000 20251227T180000 0.03000 Update 2025. Digital integrity of the human person, A new fundamental right. Every human evolves today in multi-dimensional physical and digital environment. If each individual is to keep its individuality and autonomy in its choices, it must be protected and given effective tools to defend its own autonomy. Recognizing that human life has been digitally extended must question ourselves on what makes us human today. Should personal data be considered as component of the person, rather than objects that can be owned by whoever collects that data? Should our digital integrity be protected? If each human person already has a right to physical and mental integrity (Swiss Constitution article 10 al.2), shouldn’t it have a right to digital integrity? Alexis Roussel has been co-authoring a book on the right to Digital Integrity. He is an advocate in digital public policies in Switzerland. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ENXTHG/ CDC Triangle Alexis Roussel PUBLISH BUTR3W@@pretalx.riat.at -BUTR3W Recap and precap of Critical Decentralization Cluster sessions en en 20251227T182500 20251227T183000 0.00500 Recap and precap of Critical Decentralization Cluster sessions PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/BUTR3W/ CDC Triangle Diego Salazar PUBLISH ZPSSNE@@pretalx.riat.at -ZPSSNE The Mask-Off Moment for Digital Identity en en 20251227T183000 20251227T190000 0.03000 The Mask-Off Moment for Digital Identity Despite decades of cryptography, security practice, and best practice deployment, digital identity remains the weakest link in systems design because its core terms stay vague while its consequences are concrete. What does it actually take to assemble a digital identity? What do different implementations share, even when they claim to be radically different? And what happens when those definitions are left elastic enough to serve whoever holds power? "The mask-off moment" tracks the convergence of capability (biometrics, sensors, AI triage, mass digitisation), institutional incentives (risk scoring, eligibility gates, compliance automation), and political will. The result is an emerging form of bureaucratic violence we are not prepared to name, much less govern. This talk traces how digital identity became weapon-ready through optimistic framing and opportunistic ambiguity, then offers a concrete frame to interrogate any proposal: what it will do on its best day, what it will do on its worst day, and which parts of the system will be impossible to “add accountability to later.” The intended audience is policymakers, technologists, designers, and civil-society people who are tired of vague promises and want a usable model that survives contact with reality. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ZPSSNE/ CDC Triangle Cade Diehm PUBLISH 7EKHXA@@pretalx.riat.at -7EKHXA Breaking into Wireless Smart Homes, Z-Wave example en en 20251227T190000 20251227T193000 0.03000 Breaking into Wireless Smart Homes, Z-Wave example You will learn: - security mechanisms and algorithms used in modern IoT smart home and smart building protocols and how they evolved, - various ways to break existing Z-Wave networks (DDOS or key stealing during inclusion), - new features in Z-Wave and Z-Wave Long Range protocol closing the described holes, PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/7EKHXA/ CDC Triangle PoltoS PUBLISH 39LAUG@@pretalx.riat.at -39LAUG Namecoin and Tor PKI 2025 en en 20251227T193000 20251227T200000 0.03000 Namecoin and Tor PKI 2025 Topics to be covered include: * How we can use Namecoin as a PKI with ~0 bytes of blockchain overhead. * How Namecoin's smart contract functionality (allowing multisig and timelocks to control updating a name) interacts with PKI use cases. * How we generalized Namecoin and Tor PKI to work with non-TLS protocols. * How revocations can be handled securely. * How we ensured anonymity (including Tor stream isolation) despite TLS implementations not providing API's for this. * How the anonymity protections actually *improved* performance. * How all of the above interoperates with existing software. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/39LAUG/ CDC Triangle Jeremy Rand PUBLISH 9MBKDN@@pretalx.riat.at -9MBKDN How to Contribute to Open Source Projects: Stack Wallet, Monero, Tor (Arti!) en en 20251227T200000 20251227T203000 0.03000 How to Contribute to Open Source Projects: Stack Wallet, Monero, Tor (Arti!) Starting with Tor and The Tor Project's new Rust project Arti (A Rust Tor Implementation), we'll walk through how to build, set up for development, and submit Pull Requests which have a good chance of being accepted. We'll proceed to Monero development, both for the original C++ codebase as well as the newer Cuprate project, a Rust Monero implementation, and what's coming for both. Finally, we'll look at how Stack Wallet incorporates and provides a UX for both Tor and Monero. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/9MBKDN/ CDC Triangle Joshua Babb PUBLISH TGC97J@@pretalx.riat.at -TGC97J "What can a mixnet do? Strategies for network-level anonymity" en en 20251227T203000 20251227T223000 2.00000 "What can a mixnet do? Strategies for network-level anonymity" PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/TGC97J/ CDC Triangle Alexis Roussel Casey Ford PUBLISH G7X9WM@@pretalx.riat.at -G7X9WM Intro to the Critical Decentralization Cluster en en 20251228T105000 20251228T110000 0.01000 Intro to the Critical Decentralization Cluster PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/G7X9WM/ CDC Triangle Diego Salazar PUBLISH PMUR9B@@pretalx.riat.at -PMUR9B Intro to Tropicsquare TROPIC01 Workshops at CDC en en 20251228T110000 20251228T112000 0.02000 Intro to Tropicsquare TROPIC01 Workshops at CDC PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/PMUR9B/ CDC Triangle PUBLISH XFRQZQ@@pretalx.riat.at -XFRQZQ Open Legal Q&A with Judith de Boer: "Can I Get Arrested for Writing Code?" en en 20251228T112000 1.00000 Open Legal Q&A with Judith de Boer: "Can I Get Arrested for Writing Code?" PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/XFRQZQ/ CDC Triangle Kirill PUBLISH SKBRPH@@pretalx.riat.at -SKBRPH iroh p2p chat over gossip en en 20251228T123000 20251228T143000 2.00000 iroh p2p chat over gossip iroh is a library to establish direct connections between two peers. The workshop will start with an overview of how iroh works and what it provides. After this we'll explore establishing connections between two endpoints before progressing to using a gossip protocol to send messages to multiple peers. At the end we should have a simplistic group chat application. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/SKBRPH/ CDC Triangle Floris Bruynooghe PUBLISH JXG9XP@@pretalx.riat.at -JXG9XP Embedding Anonymity Directly in your Application en en 20251228T143000 20251228T163000 2.00000 Embedding Anonymity Directly in your Application Anonymity is more important than ever, and it's not an easy job. Our job is to make it easier! The I2P project is excited to demonstrate 2 new projects, the `go-i2p` and `emissary` embedded router projects. We'll look at how they work and why they're an easier, more accessible way of providing anonymity to your users than freestanding external services. Primary target audience is Go, Rust, and C developers, I2P library developers, and people working on anonymous P2P applications. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/JXG9XP/ CDC Triangle idk PUBLISH SANGLF@@pretalx.riat.at -SANGLF Zero-Knowledge Proofs Workshop en en 20251228T163000 20251228T173000 1.00000 Zero-Knowledge Proofs Workshop PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/SANGLF/ CDC Triangle Freeman Slaughter PUBLISH CDSLJX@@pretalx.riat.at -CDSLJX Radicle: P2P, Censorship-Resistant Code Collaboration Based on Git en en 20251228T173000 20251228T180000 0.03000 Radicle: P2P, Censorship-Resistant Code Collaboration Based on Git Today, much of the open-source ecosystem depends on a few centralized code forges, even though modern version control systems are designed with fully distributed collaboration in mind. This creates questionable dependencies with regards to governance and supply-chain security. In this talk, we explore an alternative: [Radicle](https://radicle.xyz/), a decentralized, peer-to-peer code collaboration stack built on Git, that empowers developers to work together while staying sovereign. Unlike traditional, centralized code forges that can impose censorship, Radicle ensures that each user retains control over their data, interactions, and collaboration, free from corporate influence. This aligns with broader movements toward decentralization, open-source software, and the democratization of internet services. We introduce the system, provide a progress update, and share what we are currently working on. Attendees gain a comprehensive understanding of Radicle’s technical architecture, its practical benefits for decentralized code collaboration, and how it contributes to a more autonomous and resilient future for open-source development. Find out more: - [FAQ of the project (radicle.xyz)](https://radicle.xyz/faq) - [*How we built a gossip layer and CRDT on top of Git* by Alexis Sellier at GitMerge 2024 (youtube.com)](https://www.youtube.com/watch?v=tsVa53SPIHc) - [Release Notes for 1.0 (radicle.xyz)](https://radicle.xyz/2024/09/10/radicle-1.0.html) - [radicle.zulipchat.com](https://radicle.zulipchat.com)d *Free your code!* PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/CDSLJX/ CDC Triangle Lorenz Leutgeb PUBLISH 9ZX9ET@@pretalx.riat.at -9ZX9ET The Bitcoin Security Budget and Its Implications A Look at the Security, Scaling and Spam Resistance of Proof of Work Cryptocurrencies en en 20251228T180000 20251228T184000 0.04000 The Bitcoin Security Budget and Its Implications A Look at the Security, Scaling and Spam Resistance of Proof of Work Cryptocurrencies Satoshi Nakamoto released Bitcoin: A Peer-to-Peer Electronic Cash System, in October 2008, https://bitcoin.org/bitcoin.pdf, during the 2008 financial crisis. The Bitcoin genesis block was mined in January 2009 launching the Bitcoin network. The design of Bitcoin has a maximum money supply of 21 million Bitcoin (BTC). The security budget consisting of the block reward and transaction fees per block is paid to the miner (creator) of each block as an incentive to secure the network. The blocks in Bitcoin are approximately every 10 minutes. The block reward is required by consensus to halve approximately every 4 years, starting at 50 BTC per block in 2009, and is currently at 3.125 BTC per block. This leads to a current annual growth rate of the total Bitcoin money supply that is below 1%. The next halving to 1.5625 BTC is estimated to occur in April of 2028. Transaction fees are currently less than 1% of the total Bitcoin security budget. It is claimed in section 6 of the Bitcoin whitepaper that: “Once a predetermined number of coins have entered circulation, the incentive can transition entirely to transaction fees and be completely inflation free”; however no evidence, theory or references are provided to support this claim. The above model, with some variations, has been followed by most of the top proof of work cryptocurrencies, including Bitcoin Cash (BCH), Litecoin (LTC), and ZCash (ZEC). There are however some notable exceptions, Dogecoin (DOGE) and Monero (XMR). Both Dogecoin and Monero have fixed block rewards. In Dogecoin this was the result of a bug in the code; however in Monero a fixed minimum block reward or tail emission was deliberately set at the constant rate 0.6 XMR per block. The blocks in Monero are approximately every 2 minutes. This leads to an annual growth rate of the total Monero money supply that is below 1%. For comparison the historical annual compounded rate of growth of the gold money supply is close to 1%. The fee market in a cryptocurrency is also highly dependent on whether the blocksize is fixed, as in Bitcoin, Dogecoin, Litecoin and ZCash or adaptive as in Bitcoin Cash and Monero. In the case of adaptive blocksizes the question becomes: Is there a penalty (cost) to increase the blocksize as in Monero or no cost to increase the blocksize as in Bitcoin Cash? A balance needs to be found in the design of a cryptocurrency between allowing for blocksize growth in order to support the transaction demand for peer to peer electronic cash, and the necessity of spam mitigation. The use of privacy preserving technologies can also have a profound impact on this balance, by increasing the transaction size, while at the same time preventing the use of censorship, as a means of spam mitigation. In Monero for example this increase will be by a factor of around 20 times, after the upcoming Full Chain Membership Proofs, plus plus (FCMP++) hard fork. This makes finding this balance in cryptocurrencies such as Monero with no option to opt out of privacy, by far the hardest. On the other hand a solution that works in Monero will also work in a cryptocurrency with a lesser degree of privacy. In the presentation we will discuss the following questions: How do the various types of fee markets: fixed blocksize, adaptive blocksize with penalty, and adaptive blocksize without penalty work? Can transaction fees replace the falling block rewards or are fixed block rewards necessary? Are there advantages or disadvantages to replacing block rewards with transaction fees? Is it possible to have a fixed block reward and still be inflation free? Do we have a peer-to-peer electronic cash system or just another kind of asset for investment and speculation using centralized financial institutions? Is a worldwide peer-to-peer electronic cash system possible now or in the foreseeable future? We will also discuss some of the broader implications PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/9ZX9ET/ CDC Triangle Francisco "ArticMine" Cabañas PUBLISH TYKHNF@@pretalx.riat.at -TYKHNF Real World Timestamping With OpenTimestamps en en 20251228T190000 20251228T193000 0.03000 Real World Timestamping With OpenTimestamps PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/TYKHNF/ CDC Triangle Peter Todd PUBLISH PH9LYH@@pretalx.riat.at -PH9LYH Recap and precap of Critical Decentralization Cluster sessions en en 20251228T195500 20251228T200000 0.00500 Recap and precap of Critical Decentralization Cluster sessions PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/PH9LYH/ CDC Triangle Diego Salazar PUBLISH 7TDXST@@pretalx.riat.at -7TDXST Passkeys : the good, the bad, the ugly en en 20251228T200000 20251228T203000 0.03000 Passkeys : the good, the bad, the ugly PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/7TDXST/ CDC Triangle btchip PUBLISH TRJTLG@@pretalx.riat.at -TRJTLG DIY Bioreactors for mycology and biohacking en en 20251228T203000 20251228T210000 0.03000 DIY Bioreactors for mycology and biohacking Mycology is one of the fastest growing hobbies in the biohacking/microbiology scene, people cultivate and grow mushrooms for their taste, nootropic properties, and even as construction materials. Bioreactors, while rarely found on a hobbyist's desk - are the proper way to carry out cultivation and innoculation of micro-organism. This talk will explain their principles in simple terms, as well as showing off the speaker's journey building a reproducible and affordable reactor. Bioreactors are not usually found in hobbyists mushroom growers yet they enable: - Very fast culture times compared to usual jars - Efficient and sterile innoculation and expansion - Cultivation not just of mycelium, but of any microorganism such as algae, or even insulin producing bacteria The demonstrator that will be presented enables not only cultivation of mycelium of all types, but also cultivation of complex micro-organisms such as insulin-producing bacteria, and other DIY-medicine goals. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/TRJTLG/ CDC Triangle Augustin Bielefeld PUBLISH YRYKY3@@pretalx.riat.at -YRYKY3 "Referendum Citoyen" the revolutionnary app en en 20251228T210000 20251228T213000 0.03000 "Referendum Citoyen" the revolutionnary app The voting app is a simple blockchain voting app, based on ZK proof generated from a french ID card. The presentation will deep dive in the tech part, first but also present the social movement that wants to bring the referendum culture in France through a voting system that is independent from the State infrastructure, but still can prove that voters are french with the ID digital signature. The voting app is Work in Progress and needs a lot of work. This is also an open call for hackers to help improve and make the app the easiest app for people. https://github.com/ReferendumCitoyen/referendum-citoyen-react-native PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/YRYKY3/ CDC Triangle Alexis Roussel PUBLISH DCJXBV@@pretalx.riat.at -DCJXBV XMPP and metadata en en 20251228T220000 20251228T223000 0.03000 XMPP and metadata PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/DCJXBV/ CDC Triangle mathieui PUBLISH PLYJF8@@pretalx.riat.at -PLYJF8 GNU Boot install party en en 20251228T223000 20251229T023000 4.00000 GNU Boot install party PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/PLYJF8/ CDC Triangle neox GNUtoo PUBLISH XF3RKT@@pretalx.riat.at -XF3RKT Programming with the TROPIC01 open architecture secure element en en 20251228T110000 20251228T130000 2.00000 Programming with the TROPIC01 open architecture secure element PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/XF3RKT/ CDC Circle Pavel Polach PUBLISH LK9MK3@@pretalx.riat.at -LK9MK3 The DarkFi super-app en en 20251228T133000 20251228T140000 0.03000 The DarkFi super-app Hi, my name is Yuki and I am part of the DarkFi community. Out of this user/community perspective I will tell you something about the philosophy of DarkFi, the anonymous tech-stack, Lunarpunk, the Desert vs Forest, RegFi vs DarkFi and the DarkFi Vision. The talk will not go to deep in the low level tech, because I am also just learning about them :) I plan to keep the talk short and have a Q&A personally after the talk, in a more 'relaxed' environment. note: As you might expect, the talk will be held in english. But I can also speak german, if needed f.e P.S: This is the first talk I will hold, I am very excited :) PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/LK9MK3/ CDC Circle Yuki PUBLISH 8VNVWK@@pretalx.riat.at -8VNVWK Making own Z-Wave (or Zigbee) device from scratch and assemble a Z-Wave (or Zigbee/Matter) controller en en 20251228T160000 20251228T180000 2.00000 Making own Z-Wave (or Zigbee) device from scratch and assemble a Z-Wave (or Zigbee/Matter) controller We will be making own Z-Wave and Z-Wave Long Range devices Z-Wave Open Source SDK an Trident IoT SDK. It will also be possible to do Zigbee devices. We will program a sensor and a switch using Z-Wave protocol and include it in a Z-Wave network. Or Zigbee. We will also browse the Z-Wave Open Source project, and how existing Trident IoT and SiLabs code differ from them. We will also install Linux version of Z-Way - Z-Wave/Zigbee/Matter Smart Home Controller. You will learn basics of Z-Wave and Z-Wave Long Range, how to include devices and set up security schemes. We will also master using Z-Way smart home controller, investigate it's API and create own Linux or ESP32-based Z-Wave or Zigbee controller. We will also discuss Z-Wave/Zigbee-to-Matter bridging. You will need a laptop (Linux, Mac or Windows) with SSH client, USB A, Google Chrome and internet access. Optionally you can use VS Code (install Trident IoT extension). Bring your Z-Wave devices with you! If you have Home Assistant Connect ZWA-2, take it too! Presentation: https://docs.google.com/presentation/d/1EJFr8toheFOOE_k4l23wkLd98NE8yb8UbnnkNd2UKqU PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/8VNVWK/ CDC Circle PoltoS PUBLISH TXTPLK@@pretalx.riat.at -TXTPLK Radicle: Setup and Introduction en en 20251228T180000 20251228T200000 2.00000 Radicle: Setup and Introduction Attend this workshop if you would like to try out Radicle. We'll set it up, and learn how to replicate a Git repository of your choice on the network. Further, learn how to use Radicle Patches and Radicle Issues for collaboration. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/TXTPLK/ CDC Circle Lorenz Leutgeb PUBLISH LGLTBV@@pretalx.riat.at -LGLTBV P2P μVMs: pluralistic composability & interoperability for decentralized networks & applications en en 20251228T200000 20251228T220000 2.00000 P2P μVMs: pluralistic composability & interoperability for decentralized networks & applications ## Topics - μVMs & unikernels - pluralistic composability via minimalistic & layered protocol design - decentralized applications & services running in cryptographically addressed μVMs - using well-known protocols as unified message passing mechanism for decentralized applications - pluralism on the P2P transport, overlay, and application layers ## Format Short introduction followed by a discussion between researchers & developers working on projects related to μVMs, P2P/NGI protocols, and their intersection. ## Context See [WaxOS](https://WaxOS.net) for a brief overview of ongoing research. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/LGLTBV/ CDC Circle tg-x PUBLISH JENEDU@@pretalx.riat.at -JENEDU New features in Bitcoin self-custody en en 20251228T220000 20251228T224500 0.04500 New features in Bitcoin self-custody PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/JENEDU/ CDC Circle Polto, Darko PUBLISH WMMFFF@@pretalx.riat.at -WMMFFF Welcome to CDC day 3 en en 20251229T102500 20251229T103000 0.00500 Welcome to CDC day 3 PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/WMMFFF/ CDC Triangle Diego Salazar PUBLISH RPPFJF@@pretalx.riat.at -RPPFJF Getting started with the Pocket Science Lab en en 20251229T103000 20251229T123000 2.00000 Getting started with the Pocket Science Lab Learn how to use the PSLab's range of onboard instruments to make measurements and output control signals. This workshop will walk you through how to: - Measure voltage and resistance using the multimeter - Measure time-series voltage with the oscilloscope - Measure time-series digital signals with the logic analyzer - Output variable voltage with the signal generator - Output digital signals with the PWM generator Choose between using the Python API or the Android application, or both! PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/RPPFJF/ CDC Triangle Alexander Bessman PUBLISH 3MUCCG@@pretalx.riat.at -3MUCCG (Outdoor) Ballooning with antennas en en 20251229T130000 20251229T131500 0.01500 (Outdoor) Ballooning with antennas Humans are ugly bags of mostly water and they and their infrastructure attenuate the RF signals we need for communication. We'll explore concepts that are possible due to miniaturisation of RF devices and their constraints. In the end we'll raise a tethered balloon with Meshcore and a Reticulum node indoors or - depending on the situation - outdoors and playfully check the range we can achieve. We'll discuss - what we trying to achieve / the problem at hand - the physical, electrical and financial constraints of our solution compared to other approaches - what changed, why can we do this in 2025 but not in 2015? In the end we'll raise a tethered balloon with Meshcore and a Reticulum nodes indoors or - depending on the situation - outdoors and playfully check the height and range we can achieve. This is a fun workshop that wants to encourage people to play with compact yet easily deployable communication infrastructure, there will be some basic maths and diagrams, but nothing intimidating. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/3MUCCG/ CDC Triangle chris PUBLISH 9LHGTD@@pretalx.riat.at -9LHGTD State of the Decentralization in Industry en en 20251229T131500 20251229T133000 0.01500 State of the Decentralization in Industry Open-source is fun and exciting, but it often gets relegated to 'hobby', but there are industry applications. Come learn about various businesses that use open-source libraries every day, and how you can turn your open-source contributions into work, lifestyle, or even changing the world. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/9LHGTD/ CDC Triangle Diego Salazar PUBLISH UKSKJF@@pretalx.riat.at -UKSKJF The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3 en en 20251229T133000 20251229T140000 0.03000 The CDC Badge: conference badge & devboard with TROPIC01 and ESP32-S3 PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/UKSKJF/ CDC Triangle dllud bobotronic PUBLISH CDCVQT@@pretalx.riat.at -CDCVQT Talk with Industry Cryptographers and Developers en en 20251229T140000 20251229T150000 1.00000 Talk with Industry Cryptographers and Developers PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/CDCVQT/ CDC Triangle Diego Salazar PUBLISH UWJ8XB@@pretalx.riat.at -UWJ8XB Leveraging LLMs for Preventing De-anonymization: Occlumask en en 20251229T150000 20251229T153000 0.03000 Leveraging LLMs for Preventing De-anonymization: Occlumask Have you ever mentioned the weather? Maybe offhandedly complained about mosquitoes? Then you may have inadvertently given away crucial bits of who you are and where you are. Occlumask is a new tool for detecting content-based anonymity leaks like this, utilizing the capabilities of large language models to provide more accurate 'coverage'. Come and learn about the reasoning behind Occlumask's development, and the various considerations that had to be made during its development. Topics covered in this talk: * How does this work fill a gap in the broader anonymity tool context of Tor, stylometry, etc? * Background of content-based data-leak prevention tools. * What is Occlumask and how does it work? * Why use an LLM for this? * Unique challenges faced by using an LLM. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/UWJ8XB/ CDC Triangle Alice Margatroid PUBLISH MWLGQW@@pretalx.riat.at -MWLGQW Occlumask Demo & Brainstorming Session en en 20251229T153000 20251229T173000 2.00000 Occlumask Demo & Brainstorming Session Occlumask still has a long development ahead of it, and we want Occlumask to be as comprehensive as possible when it comes to detecting potential content-based data-leaks. In this workshop, we will be demoing a prototype of Occlumask for you to try. Alongside this, we will be asking how you would likely be using Occlumask, and what you think Occlumask should do for you. Come if you have ideas on: * What information do you consider important/sensitive? * What kinds of situations should Occlumask be able to handle? PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/MWLGQW/ CDC Triangle Jeremy Rand Alice Margatroid PUBLISH AEQPXC@@pretalx.riat.at -AEQPXC SocksTrace: Preventing Proxy Leaks in Your Applications en en 20251229T173000 20251229T180000 0.03000 SocksTrace: Preventing Proxy Leaks in Your Applications SocksTrace is a Linux-based proxy leak detector and traffic proxifier built on seccomp-notify. By intercepting network syscalls directly in the kernel, it provides runtime-agnostic visibility and enforcement that works even for statically linked binaries and modern browsers. The talk showcases real WebRTC-related proxy leaks discovered using SocksTrace, explains shortcomings of traditional tools, and demonstrates transparent SOCKSification, DNS enforcement, and safe handling of applications that launch their own Tor instances. We conclude with practical use cases and future directions for syscall-level network containment. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/AEQPXC/ CDC Triangle Robert Mindo PUBLISH VG7YRC@@pretalx.riat.at -VG7YRC qaul - Decentralized Off-the-Grid Mesh Communication App en en 20251229T180000 20251229T183000 0.03000 qaul - Decentralized Off-the-Grid Mesh Communication App PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/VG7YRC/ CDC Triangle Mathias Jud PUBLISH DVEGM7@@pretalx.riat.at -DVEGM7 Decentralized Syndication — The Missing Internet Protocol en en 20251229T183000 20251229T190000 0.03000 Decentralized Syndication — The Missing Internet Protocol I have implemented a conceptual decentralized content sydication platform and would like to tell more about the philosophy behind it. The workshop will consist of two parts: 30 min presentation about the concept and 30 min workshop where participants would try to publish their social post on RSDS network. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/DVEGM7/ CDC Triangle Tautvilas Mečinskas PUBLISH ZKYJ8N@@pretalx.riat.at -ZKYJ8N A Brief History of Keeping Secrets en en 20251229T190000 20251229T193000 0.03000 A Brief History of Keeping Secrets PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ZKYJ8N/ CDC Triangle Brandon Goodell PUBLISH AGLZXP@@pretalx.riat.at -AGLZXP Pre-Quantum to Post-Quantum Cryptography en en 20251229T193000 20251229T203000 1.00000 Pre-Quantum to Post-Quantum Cryptography PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/AGLZXP/ CDC Triangle Freeman Slaughter PUBLISH ZGADCJ@@pretalx.riat.at -ZGADCJ be-BOP: Ethical Commerce, Without the Middlemen en en 20251229T203000 20251229T210000 0.03000 be-BOP: Ethical Commerce, Without the Middlemen **be-BOP is free and open-source software for sovereign commerce.** It’s built on a simple belief: merchants and communities should own the tools they depend on. We design technology that respects privacy, rejects dark patterns, and removes the need for accounts or intermediaries. Our vision is trade without platforms, data brokers, or gatekeepers — commerce as a public good, not a private empire. Unlike fragmented “self-commerce” tools, **be-BOP is a complete, batteries-included stack**. It supports e-commerce, point-of-sale, restaurant systems, ticketing, peer-funding, and subscriptions — all self-hosted, interoperable, and designed for real-world merchants. It aims for the reliability of a platform, without the capture of one. Adoption grows from the edges: merchants and cooperatives seeking independence, and creators tired of surrendering revenue to platforms. In **Goma**, communities use be-BOP to organize resources and stabilize local economies under pressure. Elsewhere, artists use it to sustain open culture without permission or lock-in. The roadmap pushes beyond software. **Multitenant be-BOP** will enable domain-specific ecosystems — tailor-made for farmers’ markets, repair collectives, or independent venues — while **cross be-BOP** will link autonomous nodes into a federation of mutual visibility. Together they answer the twin failures of centralized commerce: loss of agency and isolation. be-BOP aspires to be more than a toolchain. It’s an experiment in rebuilding economic infrastructure on open terms — a foundation for **free, federated, and sustainable digital economies** that can’t be quietly “enshittified.” PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ZGADCJ/ CDC Triangle Roos PUBLISH XPN8AE@@pretalx.riat.at -XPN8AE Applying cryptoanarchy in individual and communal sovereignty en en 20251229T210000 20251229T213000 0.03000 Applying cryptoanarchy in individual and communal sovereignty PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/XPN8AE/ CDC Triangle Mario PUBLISH WWSYUL@@pretalx.riat.at -WWSYUL On the Limits of Decentralization en en 20251229T213000 20251229T230000 1.03000 On the Limits of Decentralization In its iterative, by now familiar format, the workshop opens with a short framing by the facilitator, introducing the inquiry and reflecting on the asymmetry of facilitation itself and its relevance to decentralization. Participants then break into smaller groups to explore the questions raised, with room for divergence, contestation and parallel lines of inquiry. The format remains intentionally open to shifts in attention, authority and coordination as the session unfolds. We reconvene toward the end to share reflections, tensions and unresolved questions rather than to converge on a single conclusion. The workshop invites participants to engage not only with ideas of decentralization but with how those ideas are enacted, sustained or resisted in practice. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/WWSYUL/ CDC Triangle Ome PUBLISH 7CVRJN@@pretalx.riat.at -7CVRJN Making own Z-Wave (or Zigbee) device from scratch and assemble a Z-Wave (or Zigbee/Matter) controller en en 20251229T110000 20251229T140000 3.00000 Making own Z-Wave (or Zigbee) device from scratch and assemble a Z-Wave (or Zigbee/Matter) controller We will be making own Z-Wave and Z-Wave Long Range devices Z-Wave Open Source SDK an Trident IoT SDK. It will also be possible to do Zigbee devices. We will program a sensor and a switch using Z-Wave protocol and include it in a Z-Wave network. Or Zigbee. We will also browse the Z-Wave Open Source project, and how existing Trident IoT and SiLabs code differ from them. We will also install Linux version of Z-Way - Z-Wave/Zigbee/Matter Smart Home Controller. You will learn basics of Z-Wave and Z-Wave Long Range, how to include devices and set up security schemes. We will also master using Z-Way smart home controller, investigate it's API and create own Linux or ESP32-based Z-Wave or Zigbee controller. We will also discuss Z-Wave/Zigbee-to-Matter bridging. You will need a laptop (Linux, Mac or Windows) with SSH client, USB A, Google Chrome and internet access. Optionally you can use VS Code (install Trident IoT extension). Bring your Z-Wave devices with you! If you have Home Assistant Connect ZWA-2, take it too! Presentation: https://docs.google.com/presentation/d/1EJFr8toheFOOE_k4l23wkLd98NE8yb8UbnnkNd2UKqU PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/7CVRJN/ CDC Circle PoltoS PUBLISH XTWLFN@@pretalx.riat.at -XTWLFN Programming with the TROPIC01 open architecture secure element en en 20251229T140000 20251229T160000 2.00000 Programming with the TROPIC01 open architecture secure element PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/XTWLFN/ CDC Circle Pavel Polach PUBLISH YPX33R@@pretalx.riat.at -YPX33R Mesh Radio Workshop en en 20251229T160000 20251229T180000 2.00000 Mesh Radio Workshop ### Building Autonomy: Mesh Radio Hardware Workshop Decentralized communication infrastructures require more than finished devices: understanding the hardware level enables critical engagement with proprietary designs and creates autonomy beyond commercial dependencies. The workshop covers complete assembly of an nRF52-based mesh node in Heltec form-factor, where participants gain practical comprehension of decentralized radio network architecture through soldering components, integrating LoRa modules, and installing firmware. Critical decentralization means not merely using distributed networks but mastering their technical foundations: building custom boards reveals trade-offs between energy efficiency, range, and cost, enables design adaptation to specific requirements, and develops capabilities for repairing and modifying existing infrastructure. Control over hardware design and firmware variants dissolves dependence on manufacturer decisions and permits experimental topologies that commercial solutions cannot accommodate. The workshop targets advanced participants with mesh operation experience, as technical fundamentals are prerequisite knowledge. PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/YPX33R/ CDC Circle Jitter PUBLISH 8UK8XJ@@pretalx.riat.at -8UK8XJ A hands-on guide for people who want to install and use Sockstrace. en en 20251229T180000 20251229T200000 2.00000 A hands-on guide for people who want to install and use Sockstrace. Workshop Plan: - Setup & Installation - Basic Usage (Detecting Leaks) - Advanced Configuration (Whitelist/Blacklist) - Q&A and Debugging (Troubleshooting common setup) PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/8UK8XJ/ CDC Circle Robert Mindo PUBLISH YSX8LU@@pretalx.riat.at -YSX8LU Zerocat Chipflasher en en 20251229T200000 20251229T220000 2.00000 Zerocat Chipflasher The Zerocat Chipflasher is a versatile device that is made for firmware replacement. Its operation requires some training and some knowledge about typical difficulties in in-system flash programming. This device comes with freedom in mind, down to details. It started as a cellar-project during the time of Snowden revelations, and now reaches a point of maturity in cooperation with the GNU Boot project. Key features that make this device a reproducable tool on GNU/Linux-Libre systems, now and in future, will be explained. You will be trained in device operation, targeting a hard-to-flash ThinkPad T60 systemboard. Successful operation should result in a successful boot of the liberated T60 laptop - but let’s see! -- https://www.zerocat.org PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/YSX8LU/ CDC Circle Zerocat PUBLISH XPKCMD@@pretalx.riat.at -XPKCMD Welcome to the last CDC day en en 20251230T102500 20251230T103000 0.00500 Welcome to the last CDC day PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/XPKCMD/ CDC Triangle Diego Salazar PUBLISH QTQHYH@@pretalx.riat.at -QTQHYH NextGraph Demo: Local First, E2EE, RDF graph DB, and a Reactive ORM SDK en en 20251230T103000 20251230T104500 0.01500 NextGraph Demo: Local First, E2EE, RDF graph DB, and a Reactive ORM SDK PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/QTQHYH/ CDC Triangle Laurin Weger PUBLISH UZPXRN@@pretalx.riat.at -UZPXRN SeedSigner DIY Bitcoin signing device build workshop en en 20251230T104500 20251230T124500 2.00000 SeedSigner DIY Bitcoin signing device build workshop Seedsigners are open-source DIY signing devices which can be built using "normal" hardware like a Raspberry Pi and act as kind of hardware wallets to sign Bitcoin transactions. Since the hardware is missing a secure element chip, the keys are saved externally, usually via self-drawn QR-codes which are read again for every use via the build-in camera. We brought a few kits with us which we sell for 45€ and build together. We will lashing the firmware on the MicroSD card and then build everything together in the 3d-printed enclosure. The kit includes: Raspberry Pi Zero 1.3 (without Wifi or Bluetooth chip), GPIO-header already soldered Display-Hat with joystick and buttons Camera 64GB MicroSD card MicroUSB to USB-C cable 3D printed enclosure 6 printed templates for self-drawn QR-Codes PUBLIC CONFIRMED Workshop https://pretalx.riat.at/39c3/talk/UZPXRN/ CDC Triangle freerk PUBLISH LZWMFU@@pretalx.riat.at -LZWMFU Whats new in Reticulum en en 20251230T130000 20251230T133000 0.03000 Whats new in Reticulum PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/LZWMFU/ CDC Triangle fluorescent_beige Liam PUBLISH 9HTCKF@@pretalx.riat.at -9HTCKF Solidarity Finance on P2P Rails en en 20251230T133000 20251230T140000 0.03000 Solidarity Finance on P2P Rails This talk will last approximately 15 to 20 minutes followed by Q&A discussion for the rest of the time. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/9HTCKF/ CDC Triangle Joshua Davila PUBLISH NBWHGM@@pretalx.riat.at -NBWHGM Who's afraid of anonymity? A philosophical and political toolkit en en 20251230T140000 20251230T143000 0.03000 Who's afraid of anonymity? A philosophical and political toolkit PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/NBWHGM/ CDC Triangle Casey Ford PUBLISH V9CPMV@@pretalx.riat.at -V9CPMV Mutual Vend - decentralized coop vending machine en en 20251230T143000 20251230T150000 0.03000 Mutual Vend - decentralized coop vending machine Come learn about how digital ledgers and peer to peer vending machines challenge existing labor rights, profit margins , and finance legalities! PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/V9CPMV/ CDC Triangle Ron Turetzky PUBLISH ZJBBSC@@pretalx.riat.at -ZJBBSC Building the next web en en 20251230T150000 20251230T153000 0.03000 Building the next web Let’s figure out - what are the ingredients of the web evolution we all actually want? First - we look into the evolution we’ve had until now - in Decentralized communication, AI, XR, Bitcoin, & other forefront technologies that shape the internet as we know it. Then - we brainstorm - What are potential outcomes of our best & worst decisions there? They will shape how we build the next web. PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/ZJBBSC/ CDC Triangle Ryta PUBLISH 9KZ3CB@@pretalx.riat.at -9KZ3CB Offworld Voyage @ 39c3: Astronaut Collectives Are Beautiful (A progress report) en en 20251230T153000 20251230T160000 0.03000 Offworld Voyage @ 39c3: Astronaut Collectives Are Beautiful (A progress report) PUBLIC CONFIRMED Talk https://pretalx.riat.at/39c3/talk/9KZ3CB/ CDC Triangle Scott Beibin Elizabeth Jane Cole