Block SDK 🧱

🤔 What is the Block SDK?

🌐 The Block SDK is a toolkit for building customized blocks. The Block SDK is a set of Cosmos SDK and ABCI++ primitives that allow chains to fully customize blocks to specific use cases. It turns your chain's blocks into a highway consisting of individual lanes with their own special functionality.

Skip has built out a number of plug-and-play lanes on the SDK that your protocol can use, including in-protocol MEV recapture and Oracles! Additionally, the Block SDK can be extended to add your own custom lanes to configure your blocks to exactly fit your application needs.

❌ Problems: Blocks are not Customizable

Most Cosmos chains today utilize standard CometBFT block construction - which is too limited.

• The standard CometBFT block building is susceptible to MEV-related issues, such as front-running and sandwich attacks, since proposers have monopolistic rights on ordering and no verification of good behavior. MEV that is created cannot be redistributed to the protocol.
• The standard CometBFT block building uses a one-size-fits-all approach, which can result in inefficient transaction processing for specific applications or use cases and sub-optimal fee markets.
• Transactions tailored for specific applications may need custom prioritization, ordering or validation rules that the mempool is otherwise unaware of because transactions within a block are currently in-differentiable when a blockchain might want them to be.

✅ Solution: The Block SDK

You can think of the Block SDK as a transaction highway system, where each lane on the highway serves a specific purpose and has its own set of rules and traffic flow.

In the Block SDK, each lane has its own set of rules and transaction flow management systems.

• A lane is what we might traditionally consider to be a standard mempool where transaction validation, ordering and prioritization for contained transactions are shared.
• lanes implement a standard interface that allows each individual lane to propose and validate a portion of a block.
• lanes are ordered with each other, configurable by developers. All lanes together define the desired block structure of a chain.

✨ Block SDK Use Cases

A block with separate lanes can be used for:

1. MEV mitigation: a top of block lane could be designed to create an in-protocol top-of-block auction (as we are doing with the Block SDK) to recapture MEV in a transparent and governable way.
2. Free/reduced fee txs: transactions with certain properties (e.g. from trusted accounts or performing encouraged actions) could leverage a free lane to reward behavior.
3. Dedicated oracle space Oracles could be included before other kinds of transactions to ensure that price updates occur first, and are not able to be sandwiched or manipulated.
4. Orderflow auctions: an OFA lane could be constructed such that order flow providers can have their submitted transactions bundled with specific backrunners, to guarantee MEV rewards are attributed back to users. Imagine MEV-share but in protocol.
5. Enhanced and customizable privacy: privacy-enhancing features could be introduced, such as threshold encrypted lanes, to protect user data and maintain privacy for specific use cases.
6. Fee market improvements: one or many fee markets - such as EIP-1559 - could be easily adopted for different lanes (potentially custom for certain dApps). Each smart contract/exchange could have its own fee market or auction for transaction ordering.
7. Congestion management: segmentation of transactions to lanes can help mitigate network congestion by capping usage of certain applications and tailoring fee markets.

📚 Block SDK Documentation

Lane App Store

To read more about Skip's pre-built lanes and how to use them, check out the Lane App Store.

How the Block SDK works

To read more about how the Block SDK works, check out the How it Works.

Lane Development

To read more about how to build your own custom lanes, check out the Build Your Own Lane.