Current work
- Longevity World Cup
- I created and host a competition to reverse biological aging. Participants compete on biological-age estimates from blood tests. I began building it in 2024, ran a public beta, and formally launched it on 16 September 2025.
Source · Launch essay · Season 2 - Immortal Combat
- A podcast I’ve hosted since 2024. I talk with researchers and people working to extend healthy life.
Selected conversations · Episode playlist
zkSNACKs and Wasabi Wallet
- zkSNACKs
- I co-founded the company in 2018 with Bálint Harmat and Gergely Hajdu to develop Wasabi Wallet. I served as its early CTO, built the technical team, and later led research. By 2020, I had handed over the CTO and code-maintainer responsibilities to concentrate on the next generation of Bitcoin privacy. The company had grown to 30 full-time contributors when I left in December 2023.
2018 account · Leadership handover · Setting Sail from Wasabi - Wasabi Wallet
- I created the Bitcoin privacy wallet, following my earlier HiddenWallet work, and led its early development. It brought CoinJoin, Tor, and private transaction discovery into one wallet. Version 1.0 was released on 31 October 2018; the second generation, released in June 2022, uses WabiSabi for CoinJoins with different amounts.
Version 1.0 · Source · Wasabi 2.0 launch account
Forbes Hungary included me in its 2020 30 Under 30 list for this work.
Bitcoin privacy protocols
- ZeroLink: The Bitcoin Fungibility Framework
- I created ZeroLink in 2017. It combines Chaumian CoinJoin with requirements for coin selection, transaction fees, and how a wallet treats coins before and after mixing. Those surrounding rules matter because a private mixing round can still be undone by later wallet behavior.
Initial commit · 2017 announcement - TumbleBit / NTumbleBit
- Nicolas Dorier and I worked on an independent implementation in 2016–2017. My contributions included wallet integration, Tor support, configuration, and documentation. The original NDSS paper names us as implementers and thanks me for discussions and suggestions. I wrote a five-part series explaining the protocol and how to try the implementation.
TumbleBit paper · Understanding TumbleBit · TumbleBit vs CoinJoin - WabiSabi: Centrally Coordinated CoinJoins with Variable Amounts
- I co-authored the paper with István András Seres, Yuval Kogman, and Lucas Ontivero. Anonymous credentials let participants register outputs of different amounts without revealing to the coordinator which inputs paid for them. Value commitments enforce the accounting. This is the protocol used in Wasabi 2.0.
Journal article, 22 October 2021 · March 2021 preprint - Pay To EndPoint (P2EP)
- I co-proposed P2EP after a group discussion and published its explanation in July 2018. Sender and receiver both contribute inputs to a payment, disrupting the assumption that all inputs belong to the sender. Nicolas Dorier’s later BIP78 Payjoin proposal acknowledges my implementation feedback.
BIP78: A Simple Payjoin Proposal
Research, analysis, and discussion
- Wasabi Research Club / Wasabi Research Experience
- I helped start these public discussions of Bitcoin privacy research in 2020. We reviewed existing protocols and invited their authors before moving on to our own WabiSabi research. The archive includes meeting agendas, notes, slides, and recordings on CoinShuffle, SNICKER, CashFusion, anonymous credentials, and WabiSabi.
Recordings · CoinShuffle++ discussion - Dumplings and CoinJoin analysis
- I built Dumplings in 2020 to derive reproducible CoinJoin statistics from Bitcoin blockchain data. It separates newly mixed coins from remixes and examines change and post-mix consolidation. This follows my earlier CoinJoin-efficiency and Wasabi-versus-Whirlpool analyses. The academic study Adoption and Actual Privacy of Decentralized CoinJoin Implementations in Bitcoin builds on and evaluates these detection heuristics.
Earlier efficiency analysis · Wasabi and Whirlpool · Transaction-analysis notes and code · Academic study - CoinJoin amount design / Sake
- Allowing different input amounts creates a practical question: how should those amounts be split into outputs? I wrote amount-organization simulations in 2020 and began Sake in December 2021, with later contributions from the team. It compares denomination strategies, equal outputs, change, fees, and block-space use. Dumplings supplies parameters from real transactions; my Wasabi 2.0 launch log compares the simulations with mainnet output decompositions.
2020 simulations · June 2022 launch log · Privacy guarantees and amount decomposition - CoinShuffle++ review
- My 2018 technical review of the protocol, organized as questions, answers, and unresolved points.
Earlier wallets and libraries
- DotNetWallet / HiddenWallet
- I wrote a cross-platform command-line wallet for the 2016 tutorial Build a Bitcoin wallet in C#. It covered wallet creation and recovery, receiving, balance and transaction history, and sending. That work developed into HiddenWallet, the precursor to Wasabi. I also contributed to the early Breeze TumbleBit wallet in 2017.
Breeze · 2018 account of the wallet projects - HiddenBitcoin / HBitcoin
- My privacy-oriented Bitcoin libraries built on Nicolas Dorier’s NBitcoin. They supported wallet and transaction handling, including full-block SPV wallet work. These are part of the history leading to HiddenWallet and Wasabi.
HiddenBitcoin - DotNetTor
- I built this .NET Core library for sending HTTP traffic through Tor’s SOCKS interface and managing Tor circuits. It supported my wallet and NTumbleBit work.
Published packages - Wallet network privacy
- I investigated how a lightweight wallet can discover its transactions without telling a server which addresses it owns. My writing examines full-block downloads, client-side filtering, Tor, and their privacy tradeoffs.
2017 design discussion · 2019 network-privacy comparison
Books and tutorials
- Programming the Blockchain in C#
- Originally written by Nicolas Dorier, with Bill Strait and me credited as co-authors. I updated and extended explanations for the second community edition and brought the book into GitHub for community development.
Author credits · My edition foreword - BitcoinGenie
- Code accompanying my 2016 tutorial on constructing Bitcoin transactions in C#. It walks through the transaction’s inputs and outputs, signing, and the serialized result.
- Rating Bitcoin Wallets
- A 2018 comparison framework expanding Jonas Schnelli’s wallet triangle. It examines privacy, trust, security, and usability in the wallets available at the time.
Other projects
- Forever Alone Programming
- My adaptation of the Agile Unified Process for solo programmers and small teams. Its four phases cover choosing an idea, checking feasibility, prototyping, construction, release, and maintenance.
- ClipboardButler
- A Windows utility that cleans tracking parameters and redirect wrappers from copied links. It runs in the system tray and applies rules for supported sites, including YouTube, X, Google, Facebook, Instagram, and Amazon.
- Nomadic Method
- A workout app that adapts a session to the time available.
Source
Other podcasts and conversations
- Pursuit of Value with Derek Mazzone
- My 2023 conversation series with Derek Mazzone, author of The Pursuit of Value: A Philosophy of Loss and Equanimity. Across eight recordings, we discuss method, value, religion, ethics, meaning, and mind.
Full series - Block Digest
- I co-hosted this Bitcoin news and technology podcast.
Example episode (2019) - The World of Strong Privacy — David Friedman
- My 2021 conversation with David Friedman about encryption, anonymous payments, reputation systems, and the future of privacy.
Research service
- MAGIC Lightning privacy grants
- I served on the 2022 review committee with Rafe and Dan Gershony.
Earlier videos
- Ketogén diéta motiváció
My first YouTube video, documenting a ten-day ketogenic-diet experiment.