# merkle Rust SDK
The merkle SDK is a great way to access our products.
## Install
Add the following to your cargo.toml file:
```toml
[dependencies]
merkle-sdk = "0.0.7"
```
## Examples
Examples are organized into individual crates under the `/examples` folder.
You can run any of the examples by executing:
```bash
# cargo run -p --example
cargo run -p examples-transactions --example transactions
```
## Listen to transactions
Get an API key for free at [mbs.merkle.io](https://mbs.merkle.io).
```rust
use merkle_sdk::prelude::Connection;
use futures::StreamExt;
#[tokio::main]
async fn main() {
let api_key = "sk_mbs_a35bf8ac729f9992a4319427df6b564f";
if let Ok(conn) = Connection::from_key(api_key).await {
let mut stream = conn.into_stream();
while let Some(txn) = stream.next().await {
println!("{txn:?}");
}
}
}
```
This library supports connections to different chains. This can be achieved using out of box builder functions:
```rust
use std::env;
use futures::StreamExt;
use merkle_sdk::{prelude::Connection, transactions::ChainId};
#[tokio::main]
async fn main() {
let api_key = "sk_mbs_a35bf8ac729f9992a4319427df6b564f"
// Create a Mainnet connection
let _conn_res = Connection::with_key(&api_key)
.mainnet()
.build()
.await;
// Create a Polygon connection
let _conn_res = Connection::with_key(&api_key)
.polygon()
.build()
.await;
// Create a BSC connection
let _conn_res = Connection::with_key(&api_key)
.bsc()
.build()
.await;
// Create a connection based on chain id
let conn_res = Connection::with_key(&api_key)
.chain(ChainId::Id(137))
.build()
.await;
if let Ok(conn) = conn_res {
let mut stream = conn.into_stream();
while let Some(txn) = stream.next().await {
println!("{txn:?}");
}
}
}
```