Bitcoin TechDays
February 12 – 13, 2019
Munich, Germany

About Bitcoin TechDays
The Munich Bitcoin Community is excited to welcome a range of international Bitcoin researchers and developers in Munich on Feb 12th and 13th, 2019.
Target audience: We want to address the local tech/developer as well as the international Bitcoin community. Some advanced technological knowledge about Bitcoin and its current challenges is required.

1st Day – Lectures
On the first day we will have lectures in the afternoon and evening.

2nd Day – Workshops
On the second day we will have long workshops in the morning and in the afternoon.
Livestream
The Live Stream is going to start on Tuesday 12th at 1:45 pm
Venues
JetBrains Event Space
MaibornWolff GmbH
Lectures Venue
JetBrains Event Space
Elsenheimerstraße 47A, 5th floor
80687 Munich
Workshop Venue
MaibornWolff GmbH
Theresienhöhe 13
80339 Munich
Speakers

Bob McElrath
Ph.D. Theoretical Physics, Bitcoin researcher, Blockchain Architect at Fidelity Investments

Adam Ficsor
CTO zkSNACKs, Wasabi Wallet founder and lead developer, privacy and fungibility researcher

Daniel Kraft
Ph.D. in Mathematics, contributor to Bitcoin Core, long-time lead dev for Namecoin, CTO at XAYA

Justin Moon
Founder BUIDL Bootcamp, Teacher for Bitcoin Development

Rene Pickhardt
Data Scientist and Lightning Researcher

Stepan Snigirev
Quantum physicist, Bitcoin hardware hacker, CTO Crypto Advance GmbH

Kilian Rausch
Product Director of Exchange Union, a DEX built on Lightning

Jörg Hermsdorf
Cloud & Blockchain System Architect, Co-Founder of CONSERVE BlockChain

James Chiang
Libbitcoin Contributor, Bitcoin Protocol Educator

Konstantin Nick
Lightning game developer, Founder of donnerlab

Daniel Wingen
Co-Founder of BlockKeeper and Bitcoin economics researcher
Schedule
Day 1 – Tuesday Feb, 12th
13:00 - 13:45
Door Opening
Check-In and welcome — Grab some snacks, drinks and mingle!
13:45 - 14:00
Welcome from your hosts
Brought to you by the Munich Bitcoin community
We are very happy to welcome a range of international researchers and developers in Munich today! Let’s learn about the currently ongoing developments and the future of the BTC/LN stack!
14:00 - 14:30
Let’s play Lightning
Konstantin Nick
Gaming monetization is terrible today.
P2P payments and microtransactions in the Lightning Network can fix that. An overview of the state and future potential of gaming in LN.
Konstantin Nick is a developer who is pioneering the usage of the Lightning Network for online games both from the technological as well as from the economics perspective.
14:30 - 15:00
Atomic Swaps on Lightning
Kilian Rausch
This talk introduces the concept of Atomic Swaps and walks through the specifics of an application on the Lightning Network.
It further discusses unresolved problems to enable a fully-fledged lightning-based DEX.
Kilian Rausch is the Product Director of Exchange Union, a decentralized network connecting digital asset exchanges, and has contributed major parts of the payment channel based architecture. He holds a M.Sc. in Information Systems and was previously the PO of Mobi at BTCC, the world’s first true global & mobile wallet for everyday people.
15:00 - 15:30
Autopilot — Shaping the future of the Lightning Network
Rene Pickhardt
With the growing amount of nodes and with the uncertainty about channel balances it becomes increasingly harder to decide with whom to open a payment channel.
In particular end users should not bother about channel management when using the Lightning Network. Recommendation engines based on statistical methods like the autopilot are supposed to help with this issue.
We look at the current landscape of autopilots (which exist for lnd and c-lightning), and we will also discuss the difficulties one faces in order to create a solid autopilot. Finally we propose a research roadmap that might help to have better autopilots in the future.
Rene Pickhardt is an independent data science freelancer. He studied Mathematics, Physics and Chinese and gathered 20 years experience in programming and software engineering. As a former front runner for the Pirate Party during the 2017 federal election he is an activist for open source, open educational resources and open access. During the recent year he started to focus his research and educating efforts immensely on Bitcoin’s Lightning Network, and is about to author one of the first books on the topic.
15:30 - 16:00
Coffee Break
Grab snacks, drinks, and mingle!
16:00 - 16:45
Game Channels — Off-chain scaling for complex interactions between participants
Daniel Kraft
Game channels allow two or more parties to perform complex interactions off-chain, in a way similar to payment channels.
For the use-case of games and other non-trivial interactions, it is especially interesting to consider situations in which the current state of the channel cannot simply be settled any time at will (as is the typical assumption underpinning alternative state-channel implementations). This creates challenges that are not touched by any other approach we are aware of. Using the concept of ephemeral timestamps, these issues can be resolved efficiently.
Daniel Kraft studied mathematics and physics at the University of Graz, Austria, where he obtained two Master’s degrees in Applied Mathematics and Theoretical Physics. He then wrote his PhD thesis about shape optimisation with the level-set method, and obtained his degree with distinction in the IGDK 1754 doctoral program (collaboration between the University of Graz and the Technical University of Munich). Daniel has published eight scientific papers in peer-reviewed journals so far in various fields, from geometric measure theory to blockchain technology. He has been involved in cryptocurrency development since 2013, and has been the lead blockchain developer for the revolutionary Namecoin and Huntercoin projects since 2014. He has also contributed to free software from Firefox, GCC and GNU Octave to Bitcoin Core. After leaving his senior developer role at Google Zurich to work full time on the XAYA project, Daniel wishes to further develop and innovate in blockchain technology.
16:45 - 17:30
DIY hardware wallets: how flexible and secure can they be?
Stepan Snigirev
DIY hardware wallets gives us more freedom in implementing features that are desirable but not available in commercial products.
Implement custom behavior and transaction types — time-locked contracts, coin join, atomic swap! Use any communication channel you want — USB, SD card, sound, SMS, magnetic tape! Make any type of authentication — pin, password, tilt-and-shake pattern, NFC card, voice! Implement any security feature — erase the keys when the wallet is moved, check the environment and geo-location! Possibilities are endless. But with freedom comes responsibility.
In this talk we will discuss how to start making your own hardware wallet, what are the pros and cons of the DIY approach and what security can you achieve with such a wallet. We will look at different frameworks, libraries and programming languages available for hardware development, discuss the security trade-offs and what attacks are possible on the DIY hardware.
This talk will be followed by the workshop on the next day where we will build our own air-gapped hardware wallet with SD card support and Electrum integration.
Stepan Snigirev learned about Bitcoin back in 2013. Some time later he started worrying about his private keys and made his own hardware wallet as a hobby project. After several iterations of the project he finally decided to move from quantum physics to Bitcoin and started working full time in a Munich-based startup Crypto Advance GmbH to develop a new hardware wallet.
17:30 - 18:30
Dinner Break
We have pizza! Grab a slice, or head outside to the shops, snack bars and restaurants next-door!
18:30 - 19:00
Digital Cash from Scratch
Justin Moon
Understand Bitcoin by implementing it.
Introduction and overview of the BUIDL Bootcamp. Learn how Bitcoin works by building it. We start with a comically stupid digital cash implementation (PNGCoin) and iteratively improve it until all major Bitcoin features have been added.
Based on Justin’s “Digital Cash” YouTube series and the huge git repo that goes along with it.
Justin Moon is a developer and founder of the BUIDL Bootcamp, a course in which he educates, teaches and instructs developers who want to contribute to or build upon the BTC/LN stack. He organizes the Bitcoin Developers Meetup group in Austin, Texas, and runs the Bitcoin Reading Group, a book club for Bitcoiners.
19:00 - 19:30
Building a payment channel with Libbitcoin BX
James Chiang
Payment channels are a Bitcoin transaction layering technique, which represents a trade-off between lower transaction costs and local security.
We will provide a deep-dive into payment channel protocol design and illustrate the protocol design trade-offs not commonly discussed (eg single vs. dual-funded channels). Finally, we will serialize all necessary transactions for a payment channel as they are constructed on the Lightning Network (with Libbitcoin BX) and open/close/sweep a payment channel on testnet, live during this session.
James Chiang is a contributor to Libbitcoin, a Bitcoin developer toolkit focused on readability, performance and scalability. He is a technical writer who has documented much of the library and provides lectures and training on the developer API. James also operates an intensive Bitcoin protocol training using the Libbitcoin Explorer (BX) command line power tool to illustrate all consensus critical aspects of the Bitcoin protocol.
19:30 - 20:00
The history and current state of privacy in Bitcoin
Adam Ficsor
Fungibility is an essential property of good money, and it is one of the few properties where Bitcoin does not perform perfectly.
In this presentation, Adam will talk about the history, the current state and the future of privacy in Bitcoin. A primer to all existing Bitcoin privacy techniques and concepts. What problems do they solve? How are they interconnected with each other? What can be an ideal combination of all these these technologies? What can be the endgame of Bitcoin’s fungibility progress?
Adam Ficsor aka nopara73 is the founder and CTO of zkSNACKs and the lead developer of its flagship product, the free and open-source Wasabi Wallet, a privacy-oriented Bitcoin wallet that has integrated Tor, CoinJoin and coin control features. But this is only the culmination of his year-long efforts researching the privacy and fungibility aspects of Bitcoin, authoring more than 100 articles on the topic. He was founding and working on a number of frameworks and related/predecessor projects. For example, he designed ZeroLink for Chaumian CoinJoin mixing, created HiddenWallet, and maintains the anonymity protocol NTumbleBit. He also created the Tor library for .NET Core, contributes to the NBitcoin library, co-authors the Bitcoin C# book, and is one of the most active developers on github entirely.
20:00 - 20:15
Short Break
Grab some refreshments!
20:15 - 21:00
On-Chain Defense in Depth
Bob McElrath
We will examine all current and proposed mechanisms for creating a “Bitcoin Vault”.
A Vault is a mechanism first proposed by Eyal et al to encumber your cold storage with a timelock, so that an attacker who manages to penetrate your cold storage or exfiltrate keys must wait out a timelock. During the time frame of this timelock, the owner has the opportunity to notice that a theft attempt is in progress via online monitoring of the blockchain, and deploy an alternative “clawback” spending mechanism to recover the funds, entirely preventing the theft. Topics covered will include the mechanism by Eyal at al, OP_PUSHTXDATA (Lau), pre-signed transactions with deleted keys (McElrath), OP_CHECKSIGFROMSTACK (O’Connor), as well as mechanisms useful to hide the fact that this alternative spending path exists (Taproot, MAST). Most of these mechanisms are dependent on future soft-fork changes to Bitcoin.
Bob McElrath is an experienced crypto-currency developer and team leader with experience in Bitcoin and Ethereum. Now a Blockchain Architect for Fidelity Investments, he previously worked on Bitcoin core and related software development for Vida Identity, bringing a new breed of infallible cryptographic financial services to Wall Street, and was a Senior Software Engineer for Bloomberg LP. He holds a PhD in Theoretical Physics and worked at CERN.
21:00 - 21:45
Bitcoin’s current challenges and its roadmap
Panel discussion and extended Q&A, with Bob McElrath, Adam Ficsor, Justin Moon, Daniel Kraft, and Rene Pickhardt, moderated by Daniel Wingen
Bitcoin has no official centrally managed roadmap; it rather emerges among the researcher and developer community, and takes gestalt over time.
A lot of knowledge seems inevitably necessary in order to be able to meaningfully contribute. In this panel, we have the opportunity to discuss the best ways to provide education, the near-future direction of the BTC/LN stack, and the importance and priorities of selected properties and features.
21:45 - 22:30
Fade-out
Grab refreshments, socialize!
22:00 - 02:00
After Party
Location: Bikini Mitte, Josephspitalstr. 17, 80331 Munich
Kick-Off of Munich's 1st bar w/ LN Payments - special drinks and LN offers
Website: www.bikini-mitte.com
Special Offers when paid via Lightning:
- Short the bankers! – 264K Sats
- A Lightning Affair – 232K Sats
- The 51% Attack – 341K Sats
- Nakamoto Konsensus – 450K Sats
- Beer – 99K Sats
Other drinks and snacks are available for purchasing with LN, but priced in EUR.
NODE: 036d1103b67ac8c4c376c1[email protected]:9735
Day 2 – Wednesday Feb, 13th
10:00 - 10:30
Door Opening
Grace Hopper Room, 2nd floor.
Check-In, grab a coffee! Some organizational words.
10:30 - 13:00
Crawling the Bitcoin Network
Justin Moon
Grace Hopper Room, 2nd floor.
Learn to connect to Bitcoin peers, send and receive messages, and crawl the Bitcoin network.
10:30 - 13:00
Cipher Node Workshop: Setting up Bitcoin ODROID full nodes
Jörg Hermsdorf
Meeting room, 3rd floor.
How to set up your fully encrypted and secure Bitcoin full node and prepare for Lightning.
For this workshop an instance of Ubuntu 16.4 or 18.4 in a virtual environment or dualboot (or as main OS), as well as, additional hardware is required.
Hardware Shopping List:
- odroid HC1 + 5V power adapter (or write us an if you could not get one in time)
- Micro SD Card 32GB
- SATA HDD/SSD (any SATA 2.5″ with at least 500GB)
13:00 - 14:00
Lunch Break
Grace Hopper Room, 2nd floor.
We have quiche and other good things!
14:00 - 18:00
How to build your own hardware wallet
Stepan Snigirev, Justin Moon
Grace Hopper Room, 2nd floor.
Introduction on YouTube
Required hardware: We will bring a few boards, but you may want to buy your own. Everything should work on one of these boards:
https://www.st.com/en/evaluation-tools/32f469idiscovery.html
or
https://www.st.com/en/evaluation-tools/32f746gdiscovery.html
You can buy them from rs-online:
https://de.rs-online.com/web/p/entwicklungskits-prozessor-mikrocontroller/9092865/
https://de.rs-online.com/web/p/entwicklungskits-prozessor-mikrocontroller/8820278/
The second board (F7) supports micro-python, so if you would like to try micro-python better to buy the F7 board. F4 has a better screen and a bit nicer form-factor.
You can also bring any other 32-bit developer board (ESP32, Arduino M0, Teensy, NXP, M5Stack, Adafruit Feather) and we will make a hardware wallet from it. All Bitcoin functionality will work on any of these boards, but driving peripherals like a display or SD card will be different. I worked with most of these boards, so we will find a way to make some fun with it.
If you are bringing your own board you can also bring extension boards for it – GPS shield / NFC reader / Bluetooth module / QR code scanner. Let’s make something totally crazy!
Don’t forget a mini-USB cable and an SD card!
Tickets
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Contact Us
This event is brought to you by the Munich Bitcoin Community and Open Blockchain Developers Meetup. Viewpoints expressed by our speakers do not necessarily represent our own. We aim to educate by putting forward the various viewpoints and opinions in the bitcoin, crypto-currency and blockchain space, encouraging discussions to enable everyone to make up their own minds. In particular, our program is not to be understood as investment advice.

Bitcoin Meetup Munich
The Bitcoin Munich community has been getting together since 2011. We organize events, workshops, and a monthly Stammtisch.
Open Blockchain Dev. Meetup
A platform for experienced developers who want to go deeper into details of the core protocols and top layers of open and public Blockchains.
Email Contact
If you need assistance, have individual questions, or want to contribute to the event in any way, you can send us an email with your inquiry.