Devcon Archive logo
Devcon Forum Blog
  • Watch
  • Event
    Event: background logo
    • Devcon 7
    • Devcon 6
    • Devcon 5
    • Devcon 4
    • Devcon 3
    • Devcon 2
    • Devcon 1
    • Devcon 0
  • Categories
    Categories: background logo
    • Cryptoeconomics
    • Devcon
    • Developer Experience
    • Coordination
    • Core Protocol
    • Layer 2s
    • Real World Ethereum
    • Cypherpunk & Privacy
    • Security
    • Applied Cryptography
    • Usability
  • Playlists

Suggested

Loading results..

View all

About Devcon —

Devcon is the Ethereum conference for developers, researchers, thinkers, and makers.

An intensive introduction for new Ethereum explorers, a global family reunion for those already a part of our ecosystem, and a source of energy and creativity for all.

  • Watch
  • Devcon
  • Forum
  • Blog

Get in touch

devcon@ethereum.org

Subscribe to our newsletter

Crafted with passion ❤️ at the Ethereum Foundation

© 2025 — Ethereum Foundation. All Rights Reserved.

devcon 5 / shrubs a new gas efficient privacy protocol

  • YouTube
  • IPFS
  • Details

Shrubs - A New Gas Efficient Privacy Protocol

Duration: 00:24:24

Speaker: Alex Gluchowski, Alexander Vlasov, Eran Tromer, Kobi Gurkan, Marek Olszewski

Type: Breakout

Expertise: advanced

Event: Devcon

Date: Invalid Date

ERC20 tokens that offer high levels of privacy to their users have been a longtime goal in the Ethereum ecosystem. To implement a privacy protocol that offers very strong privacy guarantees such as those of Zcash, it's necessary to maintain a large Merkle tree of commitments. Unfortunately, doing so in a smart contract can be expensive. For example, to support the same number of total transactions as Zerocash (2^64), one would require a tree depth of 64, and thus 64 storage updates per transaction, which is prohibitively expensive gas-wise. In this work, we introduce a new Merkle tree variant, which is defined not by the root, but by the path to the rightmost non-empty leaf node (or frontier), in a tree filled from left to right. This allows commitments to be inserted with O(1) amortized updates, at the expense of a slightly more complicated zk-SNARK proof, used to prove that the commitment is in the tree. We use this new data structure to create ShrubsToken, a new gas efficient privacy token, with Zcash-like privacy. Based on our experiments, we estimate that Shrubs will use around 500,000 gas per transaction, after the next Ethereum hard fork.

Categories

Privacytechnical
  • Related
Hodor - open source zkSTARKs library by Matter Labs preview
Devcon
Breakout
1:20:31

Hodor - open source zkSTARKs library by Matter Labs

"Hodor" (let's be original and don't use Marvel Universe) is an open source implementation of zkSTARKs over prime field (initially) that is currently being developed by Matter Labs and expected to be released early-mid September. In this workshop I'd like to cover some information about zkSTARKs such as arithmetization and prover/verifier work, as well as give concrete examples how to use "Hodor".

A trustless Ethereum mixer using zero-knowledge signalling preview
Devcon
Breakout
19:08

A trustless Ethereum mixer using zero-knowledge signalling

Since Ethereum transactions are fully visible on-chain, it is possible to trace value transfers and surveil users' financial activity. This state of affairs deprives users of privacy beyond mere pseudonymity. Some workarounds, like using a centralised exchange wallet or a custodial mixing service, however, introduce a high degree of counterparty risk. The Ethereum ecosystem needs a noncustodial mixer which works through strong cryptography, rather than blind trust. To solve this, we present a trustless mixer for Ether and ERC20 tokens. It builds upon Semaphore, a zero-knowledge signalling system by Barry WhiteHat and Kobi Gurkan. Additionally, it employs a burn relay registry which incentivises third parties to pay gas fees on behalf of mixer users. In this presentation, I will show a high-level architectural overview of the mixer, dive into its underlying zero-knowledge circuits, and discuss other applications of zero-knowledge signalling.

Keynote: Lessons learned from Tor preview
Devcon
Talk
31:51

Keynote: Lessons learned from Tor

I will share lessons learned during Tor's twenty years as free software fighting for privacy and human rights. We'll talk about distributed trust and privacy by design, how to help people understand the good uses of your tech, getting allies in both cypherpunks and government, why transparency and community-building are so essential to trust, and successes from other spaces. It may seem like the crypto wars never really end, but we all have a part to play in saving the world.

Keynote: Make Ethereum Cypherpunk Again: Why we need privacy preview
Devcon
Talk
26:12

Keynote: Make Ethereum Cypherpunk Again: Why we need privacy

The Web3 revolution seeks to address the sins of Web2. However, in doing so, it’s created an even worse outcome for users - users’ data is publicly available and makes them vulnerable to state-level censorship and adverse actions. This talk will address the philosophical as well as practical considerations of privacy in Web3. Privacy is an industry-wide issue and sits at the heart of all that is Web3. Understanding why privacy matters involves recognizing that it is not an isolated concept bu

Keynote: Glass Houses and Tornados preview
Devcon
Talk
15:04

Keynote: Glass Houses and Tornados

The Tornado Cash sanctions and criminal prosecutions have challenged longstanding assumptions within crypto about the limits of money transmission licensing, money laundering statutes, and sanctions laws. They've also revealed a longstanding assumption from some in policy and law enforcement circles: that blockchains have always been and must remain transparent. Neither assumption has served us well and the time has come for legal certainty. This talk is about how we get there.

Tending the Infinite Garden: Organizational Culture in the Ethereum Ecosystem preview
Devcon
Talk
23:47

Tending the Infinite Garden: Organizational Culture in the Ethereum Ecosystem

This presentation will discuss the findings of the academic paper "Tending the Infinite Garden: Organisational Culture in the Ethereum Ecosystem" by Dr. Paul-Dylan-Ennis and Ann Brody. Our study examines the decision-making processes fundamental to Ethereum's protocol governance, drawing on interviews with Ethereum's core developers. We identify a central worldview in Ethereum known as the "Infinite Garden" and discuss how Ethereum's social layer is crucial for upholding cypherpunk values.

Mixing based privacy mechanisms are insufficient preview
Devcon
Breakout
05:57

Mixing based privacy mechanisms are insufficient

Mixing based privacy-preserving mechanisms like trustless coinjoin used by Wasabi wallet and ring signatures used by Monero are noble and might work for the average Joe, but they don't provide privacy required for mission-critical things. The talk will briefly cover some of the attack vectors against such mechanisms and provide tips on improving your privacy within such systems.

Keynote: How to Properly Open Source Software:  Lessons Learned from the Linux Foundation preview
Devcon
Talk
25:44

Keynote: How to Properly Open Source Software: Lessons Learned from the Linux Foundation

It can be challenging to properly open source software: there are licenses, IP, security reporting, and many other issues that need to be addressed. In this talk, we will discuss the best practices for open source software development learned from almost 25 years of experience at the Linux Foundation. Attendees will learn about how to set up their projects for a variety of potential goals, including things like maximizing security and community building.

Lunarpunk Endgame preview
Devcon
Talk
26:29

Lunarpunk Endgame

Global surveillance is a static world where change is surpressed and society cannot evolve. In contrast, an anonymity-enhanced world resembles a forest. New civilizational experiments blossom like flowers, radiating outward from the freedom-fighters of the future. The lunarpunk end game is to enable a new ecology of social orders. This talk will describe the grand vision of lunarpunk: multipolar space-faring civilization, human speciation, and the reproduction life throughout the cosmos.

Decentralizing Ethereum Data with VulcanizeDB preview
Devcon
Talk
31:52

Decentralizing Ethereum Data with VulcanizeDB

Ethereum is a robust platform for decentralized applications, but the same data structures and encodings that make it effective and trustless also complicate data accessibility and usability. How do you know token balances were updated correctly after you sent your transaction? Is an address authorized to seize your assets? How have system parameters changed over time? To answer these questions, we’ve traditionally depended on centralized APIs and block explorers to capture and serve historical data in a performant way. But what if those services shut down or returned modified results? VulcanizeDB has been working hard to address this problem - aiming to make it easier for anyone to set up, maintain, and query their own data directly. The good news: it is possible to keep track of the historical state of smart contracts without storing petabytes of data! The tricky part: you need to be intentional about how you track information, and you need to aggregate data from disparate sources to provide a holistic view. This workshop will provide a demo and hands-on experience walking through how VulcanizeDB simplifies the process of developing and interacting with smart contracts while keeping our applications and data independent of centralized third parties.