Rust

Use full service RPC for fetching latest blockhash.

use solana_client::rpc_client::RpcClient;
use solana_sdk::{message::Instruction, pubkey, pubkey::Pubkey, signature::Keypair, signer::Signer, transaction::Transaction};
use base64::{Engine as _, engine::general_purpose};

const NOZOMI_ENDPOINT: &str = "https://nozomi.temporal.xyz/api/sendTransaction2?c=<YOUR_API_KEY>";
const NOZOMI_TIP: Pubkey = pubkey!("TEMPaMeCRFAS9EKF53Jd6KpHxgL47uWLcpFArU1Fanq");
const MIN_TIP_AMOUNT: u64 = 1_000_000;

const SOLANA_RPC_ENDPOINT: &str = "https://api.mainnet-beta.solana.com";

fn send_nozomi_txn(
    ixns: &mut Vec<Instruction>,
    signer: &Keypair,
    nozomi_endpoint: &str,
    solana_rpc_client: &RpcClient
) -> Result<(), Box<dyn std::error::Error>> {
    let tip_ixn = solana_system_interface::instruction::transfer(
        &signer.pubkey(),
        &NOZOMI_TIP,
        MIN_TIP_AMOUNT
    );
    ixns.push(tip_ixn);

    let blockhash = solana_rpc_client.get_latest_blockhash()?;
    let txn = Transaction::new_signed_with_payer(
        ixns,
        Some(&signer.pubkey()),
        &[signer],
        blockhash
    );

    let txn_bytes = bincode::serialize(&txn)?;

    let txn_base64 = general_purpose::STANDARD.encode(&txn_bytes);

    let client = reqwest::blocking::Client::new();
    let response = client
        .post(nozomi_endpoint)
        .header("Content-Type", "text/plain")
        .body(txn_base64)
        .send()?;

    // api v2 does not return a signature, just check for success
    if response.status().is_success() {
        Ok(())
    } else {
        Err(Box::new(response.error_for_status().unwrap_err()))
    }
}

fn build_ixns() -> Vec<Instruction> {
    // your instruction building logic here..
    vec![]
}

fn main() {
    let solana_rpc_client = RpcClient::new(SOLANA_RPC_ENDPOINT.to_string());

    // replace with actual keypair loading logic
    let signer = Keypair::new();

    let mut ixns = build_ixns();

    if send_nozomi_txn(
        &mut ixns,
        &signer,
        NOZOMI_ENDPOINT,
        &solana_rpc_client
    ).is_ok() {
        println!("Transaction sent successfully");
    }
}