Resources

Links to projects, guides, articles, videos and any related content.

Projects

Light Clients - SPV

• Inter-Blockchain Communication Protocol - The IBC specification used in Cosmos' cross-chain communication protocol
• Interlay - Swaps
• Ethereum BTC Relay - A BTC relay on Ethereum
• Stateless BTC Relay - An improved stateless BTC relay on Ethereum

Proof Of Authority (PoA) Validator set

• Chainswap - Swaps
• LayerZero - Generalised cross-chain message passing
• Multichain - Generalised cross-chain message passing
• Synapse - Swaps
• Wormhole - Generalised cross-chain message passing
• Hop - L2 <-> L1 swaps
• Router Protocol - Generalised cross-chain message passing

Proof Of Stake (PoS) Validator Set

• Abacus - Generalised cross-chain message passing
• Axelar - Generalised cross-chain message passing
• Cross-Consensus Message Format (XCM) - The XCM specification used in Polkadot's cross-chain communication protocol
• THORChain - Swaps

Optimistic

• Connext - Liquidity Network on top of Nomad
• NEAR Rainbow Bridge - Swaps between ETH and NEAR
• Nomad - Generalised cross-chain message passing
• Across - Swaps on top of UMA

Hashed Timelock Contract (HTLC)

• Bitcoin Lightning - Swaps between Bitcoin and Bitcoin Lightning

Articles, Papers

• Blockchain Bridges: Building Networks of Cryptonetworks by Dmitriy Berenzon
• Clusters: how trusted & trust-minimized bridges shape the multi-chain landscape by Mustafa Al-Bassam
• Ethereum Bridges Documentation - The ethereum bridges
• Optimistic Bridges: A New Paradigm for Crosschain Communication - An overview of the optimistic design for cross-chain communication
• SoK: Communication Across Distributed Ledgers - Systemization of Knowledge for the cross-chain domain
• The Interoperability Trilemma - The trillema of interoperability
• Trustless Bridging II: Byzantine Fault Tolerance: Securing light client-based bridges in the event of byzantine attacks
• With Bridges, Trust is a Spectrum - The different trust assumptions that exist in cross-chain protocols

Podcasts, Videos

• Axelar: Solving Interoperability across Blockchains - An overview of Axelar
• Burning Bridges: The Pitfalls of Multisig Bridges - What are the common pitfalls of Multisig Bridges
• CSCON[0] Breaking Down Bridges -
• Cross-app Communication Panel - The state of cross-chain communication and it's challenges
• HTLCs Considered Harmful - SBC '19 - The design drawbacks of HTLCs
• MIT Bitcoin Expo 2019 - Non-Atomic Swaps - Use a Bitcoin SPV on Ethereum for non-atomic swaps between ETH and BTC
• The Zero Knowledge Podcast: Designing Optimistic Interoperability with Nomad - An overview of Nomad and it's optimistic design
• The Zero Knowledge Podcast: Through the Wormhole with Jump Crypto - An overview of LayerZero and the tradeoffs of Validator Bridges
• The problem with cross-chain Governance - An overview of cross-chain Governance and Nomad's solution
• Whiteboard Series with NEAR | Ep: 12 James Prestwich from Summa - An overview of cross-chain designs with a focus on stateless SPVs

Discussions

• Bridge Risk Framework - Discussion on L2Beat on creating a Risk Framework for Bridges

Tutorials

• Cross-chain testing with Foundry - Example on cross-chain testing with Foundry

Zero Knowledge Interoperability

• Geometry presents: Slush, a proposal for Fractal scaling - A fractal design of cross-domain bridges between rollups
• Zero-Knowledge Proofs in Cross-Chain Communication - A sketch on using Zero-Knowledge proofs for cross-chain communication

Cross-Domain MEV

• Overcommitted: MEV in Message Passing - Where MEV exists in cross-chain communication
• MEV at the liquidity layer of bridges - Where MEV exists in cross-chain liquidity networks
• The multichain world is centralized 🙁 - studying cross-domain MEV - What is cross-chain MEV?
• Unity is Strength: A Formalization of Cross-Domain Maximal Extractable Value- First approach in formalizing cross-domain MEV

Job Board

Find a gig in the interoperability space!

• Abacus
• Axelar
• Connext
• LayerZero
• Multichain
• Nomad
• Spanning Labs
• Wormhole

Tools

• Dora - Cross-chain focused block explorer
• Foundry - Testing framework that supports cross-chain

License

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