Layer 2s

A Better Mental Model for Rollups, Plasma, and Validating Bridges

Sidechains, Plasma, Rollups, Valdiums, AnyTrust, PoS chains, Crypto Exchanges, all have one thing in common: the bridge. This talk provides an overview on the trust assumptions, threat model, security goals and solutions associated with the humble bridge smart contract. As we will see, rollups emerged because of the scalability bottlenecks faced by Ethereum, but the product-market fit is solving the operational security issues for bridging funds from Ethereum to an off-chain system.

A Layer 2 Standards Working Group

The L2 ecosystem needs standards! We formed a L2 standards working group as an EEA Community Project, managed by OASIS. We will provide a quick overview of L2 standards discussion topics thus far. Others in the L2 ecosystem are invited to join and participate in existing discussions or raise new topics. https://github.com/eea-oasis/L2

Account Abstraction on StarkNet

An overview of how native account abstraction looks on StarkNet.

An Overview and Wishlist for Rollup Escape Hatches

Escape hatches are meant to be a way to exit assets or state from a rollup in the hopefully unlikely event that sequencers are offline. In this talk, we review which projects have these hatches and what plans are publicly available for future rollups or versions of these rollups. We list some ideas that these, and other rollups, may implement or adopt in the future, for more robust and secure rollups. The suggestions will be rooted in our concern for security and the issues presented by bridges.

AltLayer: Runtime Execution and Elastic Scaling Layer for Ethereum

(1) Multi-VM Support: AltLayer enables Ethereum with on-demand EVM/WASM execution layer. (2) Elastic Scalability: To handle surge requests on Ethereum, AltLayer enables dApps to quickly spin off custom execution layer (flash layers) to serve users, with near-instant finality(<2s), low gas fees (<0.01USD) and high throughput(~2,000 tps). (3) Ubiquitous Verification: To embrace decentralization, AltLayer runs multiple block producers/verifiers including commodity machines, browsers for users.

Building a Layer-2 NFT Bridge

Cross-chain communication is one of the most complex and interesting parts of multi-chain development. In this workshop we’ll build out an NFT bridge from the ground up between Ethereum and Arbitrum covering all you need to know about bridging design and cross chain messaging. You’ll walk out with a set of smart contracts you can use to bridge your mainnet NFT collection along with way more than you ever wanted to know about bridging.

Build a DApp on Optimism: How to Conquer L2 Bridging

L1 to L2, L2 to L2, L2 to L1...bridging is complicated, messy, and difficult! In this workshop, we'll teach you how to easily build a DApp that leverages Truffle's L2 Bridge Box, which helps you quickly set up a DApp configured to handle all the complexities that come with L2 bridging.

Demystifying L2 Transactions

Transactions executed on rollups have a different lifecycle to L1 transactions. In this hands-on workshop, for devs and users alike, we’ll use Arbitrum as a demonstration tool to send transactions, follow them through their different stages of finality and analyse what fees they pay.

ELI5: Scaling Ethereum

Everything you wanted to know about approaches to scaling Ethereum

ENS Cross Chain Integration Strategy

In general, most cross chain use cases are “asset transfer” for bridges to cross tokens from one chain to another then each application deploys the exact copy from L1 to other chains. However, ENS (Ethereum Name Service) has a set of unique challenges because ENS functions as a “global address book” to resolve addresses on any chains from any wallets. We have received lots of requests from chains and dapp developers about how to integrate ENS into their chain of choice and I am going to explain

Fast and Furious Withdrawals from Optimistic Rollups

Bridges are very complex and have under-explored security issues. The issue we are focused on with withdrawing from L2, which requires L1 to be absolutely sure of what occurred on L2 (finality was reached) and current proposals like Offchain Lab’s Arbitrum require 1 week for finality. In this talk, we discuss the three designs for “fast” withdraws that allow a user to move Layer 2 to Layer 1 instantly, while a counter-party takes the risk that the withdraw will not finalize.

Fuel: Scaling Ethereum with the Fastest Modular Execution Layer

Fuel is the fastest modular execution layer. It brings UTXO-based parallel transaction execution, a more flexible transaction format, a more efficient virtual machine, and a superior vertically-integrated developer stack to Ethereum. From the creator of optimistic rollups, this exclusive talk will discuss how users and developers will be able to leverage Fuel for global scale, without having to sacrifice decentralization or the security of Ethereum.

How Bridges Improve L2 Composability

Two of the biggest arguments against L2s are that they are breaking composability and interoperability. DApps are deployed as stand-alone apps in each L2 with limited ability to communicate with each other. This leads to silos and several issues in terms of capital efficiency, governance, security, user experience and maintenance. We will explore how bridges should become the interoperability layer that will connect all the protocol “silos” across L2s, by using secure message passing.

Join the Swarm: how to run a light node or full node

Swarm is a decentralised data storage and distribution technology. In this workshop you can learn how to use Swarm, including running light node or a full node. Also there will be a demo for node operators looking to profit from storage incentives and they will be able to join the network.

Major Trends in the Layer 2 Ecosystem: Where We Are and Likely Upcoming Themes

The Layer 2 space moves at lightning speed. Just as we start to grasp a particular concept or protocol, changes and new ideas flood the ecosystem. It is exciting and fast-paced, but it can be difficult to maintain an accurate birds' eye view of current developments and upcoming themes. This lightning talk will quickly survey the Layer 2 field and make some predictions around what themes we are likely to see in the coming months.

MEV Capturing AMMs(McAMMs)

A prevailing thought is that the power of transaction ordering is mostly in the hands of block-builders in the current MEV-Boost and PBS specifications. This talk will present a new AMM design, which could shift the transaction ordering power, at least partly, to AMM designers and liquidity providers. These constructions would allow AMMs to capture part of the MEV that is currently only harvested by block-builders and proposers.

New Paradigms by Non EVM Compatible L2s!

As L2s become bigger, several like StarkWare, Aztec and Fuel have built a VM that doesn't resemble the EVM for multiple reasons. EVM is great. We love the EVM. But non-EVM based L2s bring about new paradigms, and innovations and expose us to new possibilities that are just not possible on the EVM. These L2s truly are expanding the scope of Ethereum and we should explore these more!

On the Path to a Rollup-Centric Future

It’s only been slightly over a year since Arbitrum launched as the first optimistic rollup that supported general EVM contract deployment. In that time many components have shifted, many users have migrated, and an entirely new generation of technology has shipped with Nitro. Now we look towards tackling the next set of challenges in working towards Ethereum’s rollup centric future, where using Ethereum will mean using a rollup.

Onboard The World Into Your Rollup dApp with BLS Wallet

Bringing non-web3 native users into a dApp is always a fraught, friction filled experience, even with cheaper transaction costs on rollups. In this talk, we will show you how you can modify a dApp using BLS signatures & a smart contract wallet to: - Embed a wallet directly in your dApp, and allow users to eject by swapping its public key. - Bundle multiple transactions into one and submit to an aggregator to lower friction & save on gas. - Pay for your user's transactions.

Optimism’s OP Stack

Introducing the OP Stack — a standardized tech stack for L2 chains. Introducing the Superchain vision — the inevitable unification of the distinct L2 chains into a single, horizontally scalable, super-sequenced, Superchain! The OP Stack is how we realize the Superchain vision.

Proving EVM Bytecode Execution in the zk-EVM

Rollups are the go-to solution to scaling Ethereum and at the heart of the Ethereum roadmap. Programmable rollups and zk-evms have gathered a lot of attention and research interest. Provers in particular, which produce cryptographic proofs of evm execution, pose challenging problems both theoretically and practically. In this talk we will present our arithmetization and proving scheme, and demo the zk-evm under development at ConsenSys, providing an EVM bytecode compatible end to end solution.

Rollups Are the Most Secure Bridges

l2beat.com has established itself as the most trusted community resource assessing security assumptions of different Ethereum scaling solutions. Each such solution has a "native" bridge allowing users to move tokens to L2, but there is a plethora of other bridges available to end users. How do they compare to "native" bridges ? What risks users face sending tokens across these bridges ?

Rollups, Shards & Fractals: The Dream of Atomically Composable Horizontal Scaling

Rollups allow blockchain to scale vertically, while preserving their trust properties. But what do we do when we reach the limits of vertical scalability? It might also be desirable to accomodate multiple rollups with different operating rules, virtual machines, or security trade-offs. Horizontal scaling solves these issues, but doesn't allow atomic composability. In this talk, we review approaches to horizontal scalability & ways to get as close to atomic composability as possible.

Scroll Pre-Alpha Testnet Upgrade

Why do we need secure scaling? How is Scroll different from existing zkRollups? What can Scroll bring to users and developers? In this 20-minute session, we will introduce the design, principles, and the whole workflow of zkEVM, demonstrate our bytecode-level compatible zkEVM on testnet, and show you how easy it is for developers to deploy smart contracts on it.

StarkNet 101 Workshop - Getting started with unlimited scalability

A 2-hour workshop introducing the StarkNet Layer 2 network, how it works, and why it provides scalability to the Ethereum ecosystem. For this, participants will learn how to harness the power of the Cairo programming language and write their first semi-complex smart contract.

Technical Details of the Opcode Compatible zkEVM

I will explain some technical details on how we, at PolygonHermez, built the opcode compatible zkEVM. This will include some design details of specific pieces like the storage, the arithmetic state machine, the keccak circuit, among others. I will also go thru some snippets of the zkASM code that emulates the Ethereum VM. I will include in the talk some performance measures and I will do a live demo of the testnet.

The Blockchain Bridge That You Dream About

In the times where scalability of blockchains depends on multiple layers, and when interoperability holds for an essential blockchain feature, bridges become critical infrastructure parts. They are meant to hold liquidity, asked to operate quickly, but they cannot benefit from the security guarantees of an on-chain application, because they inherently contain off-chain components. In this talk, we discuss the properties of a bridge that is secure and meets all the needs for it to be useful.

The State of Fiat On-Ramps for Layer 2s

In this talk, Thijs Maas, the CEO of Onramper, shall share unique insights into the fiat on-ramp market for layer 2s, using data on fiat on-ramps. We shall demonstrate the gaps in current layer 2 on-ramp coverage.

Understanding L2: Ordering and Execution (aka Everything You've Always Wanted to Know About Sequencers But Were Afraid To Ask)

Overview of design patterns in handling ordering and execution; will cover separation of roles between sequencers and validators, tradeoffs in different ways handing execution & ordering, current approaches — i.e., what various L2 rollups are doing in production, what is and isn't possible in principle.

Using a Hybrid UTXO and Account-based State Model in a ZK Rollup

Many rollups choose to follow Ethereum’s account-based state model. We explore an alternative approach: a hybrid of a UTXO and an account-based model, specifically in a context of a ZK rollup. This approach offers a number of interesting properties including local transaction execution, support for privacy-preserving smart contracts, and reduced state bloat. In this talk we describe tradeoffs between different state models and cover the specific design choices we’ve made with Polygon Miden.

Ups and Downs: Onboarding a Million Users to Layer-2

In the last year we’ve seen thousands of projects and billions of dollars migrate over to rollups. Liquidity and users have started aggressively migrating, but there’s still a long way to go. In this talk we’ll cover successful use cases, pain points that make it challenging for both users and developers to onboard, and emerging projects and protocols in the layer 2 space that are showing a lot of promise.

zkEVM Vs EVM: Full Equivalence?

At Polygon-Hermez we have bet for the zero-knowledge EVM to solve Ethereum scalability. We will talk about what is the ZK-EVM and how are we dealing with it at Polygon. We will explain the differences between zkEVM and EVM, Also the main challenges, tricks, tech decisions and differences we had to apply to achieve EVM compatibility will be explained.