Cosmos SDK is a modular blockchain framework for building custom Layer 1 chains with native interoperability.
The framework addresses the challenge of creating secure, high-performance blockchains from scratch by providing a composable architecture of predefined modules covering standard blockchain functionality. Developers can use these modules as-is or create custom ones for specific use cases. The SDK handles abstractions for permissioning, governance, state management, account abstraction, tokenization, and application logic. Interoperability is built in through native integration with the Inter-Blockchain Communication Protocol, enabling blockchains to communicate across the Cosmos ecosystem. The framework is designed to work with any consensus engine but pairs with CometBFT, a battle-tested Byzantine Fault Tolerant state machine optimized for high throughput and configurability.
Cosmos SDK suits teams building application-specific blockchains that require full customization and sovereignty. It is particularly valuable for projects needing cross-chain communication out of the box and those that want to avoid the constraints of smart contract platforms. The framework is production-ready, with over two hundred chains already deployed using it. Beyond core modules, the project maintains enterprise-grade modules in a separate directory for specialized use cases like permissioned networks and consortium chains, with different licensing terms than the core SDK. Developers should use the latest maintained Go version when building applications with the framework.
The project maintains active documentation including a high-level architectural introduction and tutorials for getting started. Core SDK modules are documented with an introduction guide. The framework is designed to integrate closely with CometBFT, with releases coordinated between the two projects as part of the broader Cosmos Stack.
