# Architecture

### Cosmos SDK <a href="#cosmos-sdk" id="cosmos-sdk"></a>

BlockX enables the full composability and modularity of the [Cosmos SDK](https://docs.cosmos.network/).

### Tendermint Core & the Application Blockchain Interface (ABCI) <a href="#tendermint-core-the-application-blockchain-interface-abci" id="tendermint-core-the-application-blockchain-interface-abci"></a>

Tendermint consists of two chief technical components: a blockchain consensus engine and a generic application interface. The consensus engine, called [Tendermint Core](https://docs.tendermint.com/), ensures that the same transactions are recorded on every machine in the same order. The application interface, called the [Application Blockchain Interface (ABCI)](https://docs.tendermint.com/master/spec/abci/), enables the transactions to be processed in any programming language.

Tendermint has evolved to be a general purpose blockchain consensus engine that can host arbitrary application states. Since Tendermint can replicate arbitrary applications, it can be used as a plug-and-play replacement for the consensus engines of other blockchains. BlockX is such an example of an ABCI application replacing Ethereum's PoW via Tendermint's consensus engine.

Another example of a cryptocurrency application built on Tendermint is the Cosmos network. Tendermint is able to decompose the blockchain design by offering a very simple API (ie. the ABCI) between the application process and consensus process.

### EVM module <a href="#evm-module" id="evm-module"></a>

BlockX enables EVM compatibility by implementing various components that together support all the EVM state transitions while ensuring the same developer experience as Ethereum:

* Ethereum transaction format as a Cosmos SDK `Tx` and `Msg` interface
* Ethereum's `secp256k1` curve for the Cosmos Keyring
* `StateDB` interface for state updates and queries
* JSON-RPC client for interacting with the EVM