Composable: Exploring Crypto’s Building Blocks (an Espresso Pod)

In this episode of Composable, hosts Alysia and Ellie welcome Hasu, an expert in MEV and the strategy lead at Flashbots. They delve into the intricacies of MEV, which stands for Maximal Extractable Value, discussing what it is in detail, its evolution, and its implications for our multi-chain future. The conversation covers topics such as private RPCs, order flow auctions, and the impact of MEV on both user experience and protocol efficiency. The episode also explores the trade-offs between synchronous and asynchronous composability and predicts future trends in crosschain MEV and protocol design.

Relevant links from the show.

• Flashbots writing
• Flashbots forum
• Archive of all MEV-related content

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode of Composable, Ellie and Alysia dive deep into one of blockchain's most critical yet confusing concepts: finality. Triggered by a real-world story of someone losing funds due to misunderstanding finality in crosschain transactions, they explore the nuanced definitions of finality, settlement, and confirmations across different blockchain layers.

The discussion reveals how finality is not a fixed concept but rather depends on trust assumptions, application requirements, and the observer's perspective. They examine how different stakeholders, from centralized exchanges to DeFi protocols, make trade-offs between speed and security when defining finality for their users.

Key topics covered: 

• Defining blockchain finality
• Finality vs settlement
• Layer 2 finality considerations
• Crosschain composability challenges
• Real-world application examples
• Developer trade-offs and decisions
• Confirmations and block times
• Variable finality factors

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode, hosts Alysia and Ellie tackle Ethereum FUD (fear, uncertainty, and doubt) head-on by rolling a special "Ethereum FUD" die—a special piece of swag that Espresso Systems produced for ETHDenver 2025—and discussing common criticisms of Ethereum. 

They cover everything from fee structures and L2 scaling solutions to fragmentation concerns and Ethereum's overall direction, diving into whether the FUD is valid or simply misconceptions and providing a balanced perspective on the challenges and design decisions facing Ethereum as it evolves.

Key topics covered:

Fees Too Low - Discussion of the criticism that low Ethereum fees indicate lack of usage and declining demand

Parasitic L2s - Debate over whether Layer 2 solutions help or harm Ethereum by potentially siphoning value from L1

Fragmentation - Analysis of liquidity and ecosystem fragmentation across multiple L2 chains

No North Star - Examination of claims that Ethereum lacks clear direction compared to competitors like Solana

Validator Economics - How fee levels impact validator profitability and network security

Product Market Fit - Challenges of finding sustainable use cases for blockchain technology

User Experience vs. Decentralization - Trade-offs between ease of use and maintaining decentralized principles

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode, Ellie and Alysia dive deep into intent-based bridges, specifically exploring Across Protocol and their proposed Across Prime upgrade. They examine how intent bridges work, their advantages over traditional bridges, and the capital efficiency improvements that Across Prime aims to deliver for solvers (i.e., the liquidity providers that fulfill user intents).

Key Topics Covered

• What are intents and intent bridges - Definition and distinction from traditional bridges, focusing on how users can move assets cross-chain without worrying about underlying mechanisms
• Intent bridge mechanics - How liquidity bridges work with solvers fronting funds on destination chains rather than actually moving tokens crosschain
• Benefits for users - Native tokens (no wrapped assets), no slippage concerns, fast transactions, and simplified user experience compared to canonical bridges
• Intent lifecycle walkthrough - Three-step process: initiate transaction, fill by solver, and settlement verification using UMA's optimistic oracle
• Solver risks and challenges - Blockchain reorganization risks, sequencer confirmation dependencies, and capital lock-up issues during settlement periods
• Across Prime proposal - New bonding mechanism that allows solvers to get paid immediately and reuse capital, dramatically improving capital efficiency
• Capital efficiency explained - How solvers can potentially earn 50+ transaction fees per hour on the same liquidity instead of just one fee per settlement period
• Technical implementation details - Merkle tree systems for tracking in-flight transactions and user-enforced verification mechanisms
• Solver rebalancing challenges - Why relayers need better native bridging options to move funds between chains efficiently
• ERC-7683 standard - Crosschain intent standardization for interoperability between different solver networks
• NFT bridging limitations - Why liquidity bridges cannot support NFT transfers due to uniqueness constraints
• Fair exchange problem - Distributed systems challenge of ensuring trustless exchanges and how Across addresses it theoretically and practically
• Future outlook debate - Whether intents represent the future of crosschain interactions or merely a stopgap until better native interoperability emerges

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode of Composable, hosts Alysia and Ellie speak with Orest from t1 about proof aggregation, TEEs (Trusted Execution Environments), L2 security, and how these concepts relate to finality. The conversation explores Vitalik Buterin's recent post proposing a "two out of three" proof system combining TEE proofs, ZK proofs, and Optimistic proofs to enhance blockchain security while improving finality times. Orest also shares how t1 is implementing TEEs to achieve faster finality times for L2s while maintaining strong security guarantees.

Key Topics Covered:

• Introduction to TEEs and how they work
• Comparison between TEE proofs and ZK proofs
• Vitalik's proposal for combining multiple proof systems
• How t1 uses TEEs for integrity rather than confidentiality
• Remote attestation process and its importance
• Security considerations and risk models for TEEs
• t1's unique approach combining TEE proofs with periodic ZK proofs
• The challenges of vendor centralization in TEE ecosystems
• Real-world tradeoffs between security, speed, and usability

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode of Composable, Alysia and Ellie explore the security of crosschain messages. They examine notable bridge attacks, analyze what makes crosschain messages vulnerable, and discuss various security approaches, including multisigs and Trusted Execution Environments (TEEs). The episode breaks down the technical aspects of securing crosschain messages while considering the trade-offs between speed and usability.

• Notable bridge attacks like Ronin, Wormhole, and Orbit
• The anatomy of crosschain messages
• Security vulnerabilities in bridge systems
• Multisig security models and their limitations
• Trusted Execution Environments (TEEs) and their role in securing crosschain messages
• Trust assumptions in various other security approaches

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode of Composable, hosts Alysia and Ellie speak with Eda Akturk, a developer advocate at Hyperlane, about intents in general and the recently released Open Intents Framework, specifically. They explore what intents are, how they're changing user experiences in web3, and dive into the collaborative effort behind the Open Intents Framework, which aims to make it easier for developers to build intent-based applications.

Key Topics Covered

• How to define intents in a blockchain context (eg, allowing users to specify their goal rather than know how to reach it themselves)
• The Open Intents Framework, a collaborative effort led by Hyperlane, Bootnode, and the Ethereum Foundation
• How the framework builds upon the ERC-7683 standard proposed by Across and Uniswap
• The framework's three main components: smart contract base, open-source solver implementation, and ready-to-use UI
• The mechanics of intent transactions and how solvers fulfill user requests
• How solvers front liquidity and manage finality risks when bridging between chains
• Target audiences for the Open Intents Framework, especially new chains and crosschain applications
• Benefits of standardization for creating composability between different intent systems
• The competitive solver market and how it leads to better UX
• The future vision for intents in the blockchain ecosystem
• The unusual level of cooperation between competing L2s and infrastructure projects

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode, hosts Alysia and Ellie explore the concept of wrapped tokens in the Ethereum ecosystem, discussing their purpose, benefits, and limitations.

Key Topics:

• Canonical vs. wrapped tokens
• Use cases for wrapped tokens
• Security implications of token issuance
• Limitations and challenges of wrapped tokens
• Bridging solutions and speed/security tradeoffs
• Future of wrapped tokens

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this episode of Composable, hosts Ellie and Alysia dive deep into the topic of synchronous composability with guest Cecilia, an engineer at Gwyneth Taiko. They explore the technical challenges of reaching synchronous composability, potential implementations to enable it, and the future value it could drive. They also examine why many prominent figures in the crypto space consider synchronous composability overrated...

Key Topics Covered:

• Synchronous vs. asynchronous composability in blockchain systems
• Technical challenges of implementing synchronous composability across different L2 chains
• Gwyneth's successful demo of synchronous composability within their cluster
• The advantages of based rollups for achieving synchronous composability
• Shared sequencing and why many chains resist implementing it
• Practical applications of synchronous composability, particularly for L2s accessing L1 liquidity
• The "one big rollup" critique and why having multiple chains with shared sequencing still makes sense
• Comparison of synchronous composability with intent-based approaches to cross-chain interactions
• The potential future of domain-specific chains using based infrastructure
• How preconfirmation protocols like Espresso could enable faster synchronous interactions between chains

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso. 

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

In this sixth episode of Composable, Alysia and Ellie explore the question of what it means to "Build Something Real" and the tension that exists today between blockchain's potential versus its current hype-filled reality.

Key Topics Covered:

• The controversial role of memecoins in crypto and whether they provide genuine value
• What it actually means to "Build Something Real" in the blockchain space
• How Web3 is rediscovering the same financial lessons that TradFi learned decades ago
• The paradigm shift of data ownership and the challenges of getting users to value it
• The current metrics used to measure value in Web3 and their limitations
• The barriers to mainstream adoption and potential solutions
• How interoperability and chain fragmentation impact developers and users
• The importance of security when building in the Web3 space
• Bull and bear cases for the future of blockchain technology

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso. 

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson

Composable is a bi-weekly podcast exploring crypto's building blocks. Hosted by Alysia and Ellie, and brought to you by Espresso.

Find us on X:
Composable — @composablepod
Alysia — @alysiatech
Ellie — @ellierdavidson