1-introduction.md

Easy Interchain Queries with CosmWasm and Polytone

In this tutorial we are going to learn how to create a cross-chain CosmWasm smart contract which has a simple counter that can only be increased if user has a minimum balance of token staked on another chain.

This is a simplified diagram of the contract we are going to build.

Environment Setup

To follow this tutorial we need to have many dependacies installed. We are going to use Rust to build the CosmWasm smart contracts and Local Interchain + Docker to spin up local chains, and Hermes to relay IBC packets across the two chains.

For the CosmWasm environment, you can follow this instructions:

• https://book.cosmwasm.com/setting-up-env.html

For Docker, you can follow the official documentation:

• https://docs.docker.com/get-started/get-docker/

For Local Interchain, you can follow the official installation guide:

https://github.com/strangelove-ventures/interchaintest/tree/main/local-interchain

Check everything is set up

Go

dimi@airbox ~ % go version
go version go1.23.2 darwin/arm64

Cargo

dimi@airbox ~ % cargo --version
cargo 1.83.0 (5ffbef321 2024-10-29)

Docker

dimi@airbox ~ % docker --version
Docker version 27.3.1, build ce12230

Local Interchain

dimi@airbox ~ % local-ic version
v8.8.0%

Hermes

dimi@airbox ~ % hermes --version
hermes 1.10.4

Next step

Continue with chains setup here