# Building Synchronous Composability: Eth Economic Zone | Philippe Schommers at Pragma Lisbon 2026

- Channel: [ETHGlobal](https://streameth.org/ethglobal)
- Date: 2026-09-09
- Duration: 16:04
- Topics: ETHGlobal, Pragma Lisbon 2026, Lisbon, 2026, Philippe Schommers, Gnosis, Ethereum Economic Zone, synchronous composability, crosschain, Gnosis Chain, atomic transactions, shared liquidity, crosschain calls, Ethereum infrastructure, Pragma Lisbon, Ethereum crosschain composability, synchronous blockchain, crosschain transactions, atomic crosschain calls, Ethereum L2 composability, Gnosis Chain infrastructure, shared crosschain liquidity, instant bridging, crosschain flash loans
- Watch: https://streameth.org/watch/yt-9crVpkNYd60
- YouTube: https://www.youtube.com/watch?v=9crVpkNYd60

## Description

Philippe Schommers, Head of Infrastructure at Gnosis, explains how the Ethereum Economic Zone can enable synchronous composability between Ethereum and compatible chains. Today, users bridge assets, wait for finality, and manage separate transactions before interacting with another network. The proposed system coordinates blocks at matching timestamps and uses composers plus crosschain proxy contracts to recognize chain boundaries, execute calls across networks, and preserve atomic behavior even when Ethereum reorganizes or one leg of a transaction must be cancelled. He explains that synchrony requires more than a fast bridge. Participating chains must reference Ethereum consistently, coordinate execution at compatible timestamps, and reverse dependent actions when the L1 reorganizes. A composer determines when execution crosses a chain boundary, while proxy contracts represent remote calls and return values. Transactions are assembled into batches so each network can execute its portion without asking Ethereum to pause while another chain runs.

Schommers describes capabilities already demonstrated on Gnosis Chain, including instant deposits and withdrawals, crosschain calls with return values, flash loans, and nested L1–L2 calls inside one transaction. The design could let an application source liquidity on another chain and return without a separate bridge flow, reducing fragmentation and improving user experience. He also addresses practical constraints: faster block times, heavy multichain simulation, validator requirements, proofs, reorgs, and missed bundles. The goal is a repeatable, fault-aware path that lets multiple chains behave like one economic environment while retaining diverse execution and proof systems. The implementation supports nested calls that can move from L1 to L2 and back several times while remaining one atomic transaction. This opens designs such as borrowing on one network, swapping against deeper liquidity on another, and returning the result without exposing the user to separate bridge steps. Schommers also distinguishes the specialized composer from ordinary validators because multichain simulation is computationally heavy.

00:00 Introduction to the Ethereum Economic Zone
00:48 Why Crosschain Bridging Is Cumbersome
01:10 One Atomic Crosschain Transaction
01:33 Swapping on L2 and Returning to Ethereum
01:56 Reorg Requirements for Synchronous Chains
02:18 A Communication Framework, Not a Stack
02:38 How the Multichain Composer Works
03:23 Simulating Transactions Across Chains
03:48 Matching Blocks and Chain Boundaries
04:10 Crosschain Proxy Contract Architecture
05:23 Returning Call Results to Ethereum
06:25 Posting Return Values Before Execution
06:54 Keeping Crosschain Calls Atomic
07:51 Live Deposits, Calls, and Flash Loans
08:20 From Devnet to Gnosis Chain
09:09 Accessing Ethereum L1 Liquidity
09:40 Remote Swaps Without Separate Bridging
10:06 Converting an Existing Live Network
10:28 Sequencing, Data Availability, and ZK
11:28 Decentralization Tradeoffs for Gnosis
11:52 Two-Second Block Time Goals
12:21 Validators and Reorg Constraints
13:29 Atomic Composability Across More Chains
14:04 Proof Diversity and Failure Modes
14:25 Devnet Roadmap and Gnosis Proposal
15:20 Invitation to Join the Open Protocol
15:52 Closing the Composability Talk

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🇵🇹 *Pragma Lisbon 2026*
Pragma Lisbon 2026 was held on June 25th at the Carlos Lopes Pavillion in Lisbon, Portugal and was an in-person summit for builders and leaders in the web3 ecosystem. Watch the full Pragma Lisbon 2026 YouTube Playlist here: https://www.youtube.com/playlist?list=PLMxB4xW8JYdk

ETHGlobal's Pragma series takes place in cities around the world, and is designed to be a different kind of event. Pragma is a one-stage conference with founders-only on stage, bringing together a small group of curated attendees and speakers to discuss the future of web3 and reflect on the past. 

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✅ Follow Philippe Schommers
X: https://x.com/filoozom

✅ Follow Gnosis
X: https://x.com/gnosischain

✅ Follow ETHGlobal
X: https://x.com/ETHGlobal​
Warpcast: https://warpcast.com/ethglobal
Website: https://ethglobal.com
YouTube: https://www.youtube.com/@UCfF9ZO8Ug4xk_AJd4aeT5HA 

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