Developing Programs in Rust
Solana programs are primarily developed using the Rust programming language. This page focuses on writing Solana programs in Rust without using the Anchor framework, an approach often referred to as writing "native Rust" programs.
Native Rust development provides developers with direct control over their Solana programs. However, this approach requires more manual setup and boilerplate code compared to using the Anchor framework. This method is recommended for developers who:
- Seek granular control over program logic and optimizations
- Want to learn the underlying concepts before moving to higher-level frameworks
For beginners, we recommend starting with the Anchor framework. See the Anchor section for more information.
Prerequisites #
For detailed installation instructions, visit the installation page.
Before you begin, ensure you have the following installed:
- Rust: The programming language for building Solana programs.
- Solana CLI: Command-line tool for Solana development.
Getting Started #
The example below covers the basic steps to create your first Solana program written in Rust. We'll create a minimal program that prints "Hello, world!" to the program log.
Create a new Program #
First, create a new Rust project using the standard cargo init
command with
the --lib
flag.
cargo init hello_world --lib
Navigate to the project directory. You should see the default src/lib.rs
and
Cargo.toml
files
cd hello_world
Next, add the solana-program
dependency. This is the minimum dependency
required to build a Solana program.
cargo add solana-program@1.18.26
Next, add the following snippet to Cargo.toml
. If you don't include this
config, the target/deploy
directory will not be generated when you build the
program.
[lib]
crate-type = ["cdylib", "lib"]
Your Cargo.toml
file should look like the following:
[package]
name = "hello_world"
version = "0.1.0"
edition = "2021"
[lib]
crate-type = ["cdylib", "lib"]
[dependencies]
solana-program = "1.18.26"
Next, replace the contents of src/lib.rs
with the following code. This is a
minimal Solana program that prints "Hello, world!" to the program log when the
program is invoked.
The msg!
macro is used in Solana programs to print a message to the program
log.
use solana_program::{
account_info::AccountInfo, entrypoint, entrypoint::ProgramResult, msg, pubkey::Pubkey,
};
entrypoint!(process_instruction);
pub fn process_instruction(
_program_id: &Pubkey,
_accounts: &[AccountInfo],
_instruction_data: &[u8],
) -> ProgramResult {
msg!("Hello, world!");
Ok(())
}
Build the Program #
Next, build the program using the cargo build-sbf
command.
cargo build-sbf
This command generates a target/deploy
directory containing two important
files:
- A
.so
file (e.g.,hello_world.so
): This is the compiled Solana program that will be deployed to the network as a "smart contract". - A keypair file (e.g.,
hello_world-keypair.json
): The public key of this keypair is used as the program ID when deploying the program.
To view the program ID, run the following command in your terminal. This command prints the public key of the keypair at the specified file path:
solana address -k ./target/deploy/hello_world-keypair.json
Example output:
4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz
Test the Program #
Next, test the program using the solana-program-test
crate. Add the following
dependencies to Cargo.toml
.
cargo add solana-program-test@1.18.26 --dev
cargo add solana-sdk@1.18.26 --dev
cargo add tokio --dev
Add the following test to src/lib.rs
, below the program code. This is a test
module that invokes the hello world program.
#[cfg(test)]
mod test {
use super::*;
use solana_program_test::*;
use solana_sdk::{signature::Signer, transaction::Transaction};
#[tokio::test]
async fn test_hello_world() {
let program_id = Pubkey::new_unique();
let (mut banks_client, payer, recent_blockhash) =
ProgramTest::new("hello_world", program_id, processor!(process_instruction))
.start()
.await;
// Create the instruction to invoke the program
let instruction =
solana_program::instruction::Instruction::new_with_borsh(program_id, &(), vec![]);
// Add the instruction to a new transaction
let mut transaction = Transaction::new_with_payer(&[instruction], Some(&payer.pubkey()));
transaction.sign(&[&payer], recent_blockhash);
// Process the transaction
let transaction_result = banks_client.process_transaction(transaction).await;
assert!(transaction_result.is_ok());
}
}
Run the test using the cargo test-sbf
command. The program log will display
"Hello, world!".
cargo test-sbf
Example output:
running 1 test
[2024-10-18T21:24:54.889570000Z INFO solana_program_test] "hello_world" SBF program from /hello_world/target/deploy/hello_world.so, modified 35 seconds, 828 ms, 268 µs and 398 ns ago
[2024-10-18T21:24:54.974294000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM invoke [1]
[2024-10-18T21:24:54.974814000Z DEBUG solana_runtime::message_processor::stable_log] Program log: Hello, world!
[2024-10-18T21:24:54.976848000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM consumed 140 of 200000 compute units
[2024-10-18T21:24:54.976868000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM success
test test::test_hello_world ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.13s
Deploy the Program #
Next, deploy the program. When developing locally, we can use the
solana-test-validator
.
First, configure the Solana CLI to use the local Solana cluster.
solana config set -ul
Example output:
Config File: /.config/solana/cli/config.yml
RPC URL: http://localhost:8899
WebSocket URL: ws://localhost:8900/ (computed)
Keypair Path: /.config/solana/id.json
Commitment: confirmed
Open a new terminal and run the solana-test-validators
command to start the
local validator.
solana-test-validator
While the test validator is running, run the solana program deploy
command in
a separate terminal to deploy the program to the local validator.
solana program deploy ./target/deploy/hello_world.so
Example output:
Program Id: 4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz
Signature:
5osMiNMiDZGM7L1e2tPHxU8wdB8gwG8fDnXLg5G7SbhwFz4dHshYgAijk4wSQL5cXiu8z1MMou5kLadAQuHp7ybH
You can inspect the program ID and transaction signature on
Solana Explorer.
Note that the cluster on Solana Explorer must also be localhost. The "Custom RPC
URL" option on Solana Explorer defaults to http://localhost:8899
.
Invoke the Program #
Next, we'll demonstrate how to invoke the program using a Rust client.
First create an examples
directory and a client.rs
file.
mkdir -p examples
touch examples/client.rs
Add the following to Cargo.toml
.
[[example]]
name = "client"
path = "examples/client.rs"
Add the solana-client
dependency.
cargo add solana-client@1.18.26 --dev
Add the following code to examples/client.rs
. This is a Rust client script
that funds a new keypair to pay for transaction fees and then invokes the hello
world program.
use solana_client::rpc_client::RpcClient;
use solana_sdk::{
commitment_config::CommitmentConfig,
instruction::Instruction,
pubkey::Pubkey,
signature::{Keypair, Signer},
transaction::Transaction,
};
use std::str::FromStr;
#[tokio::main]
async fn main() {
// Program ID (replace with your actual program ID)
let program_id = Pubkey::from_str("4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz").unwrap();
// Connect to the Solana devnet
let rpc_url = String::from("http://127.0.0.1:8899");
let client = RpcClient::new_with_commitment(rpc_url, CommitmentConfig::confirmed());
// Generate a new keypair for the payer
let payer = Keypair::new();
// Request airdrop
let airdrop_amount = 1_000_000_000; // 1 SOL
let signature = client
.request_airdrop(&payer.pubkey(), airdrop_amount)
.expect("Failed to request airdrop");
// Wait for airdrop confirmation
loop {
let confirmed = client.confirm_transaction(&signature).unwrap();
if confirmed {
break;
}
}
// Create the instruction
let instruction = Instruction::new_with_borsh(
program_id,
&(), // Empty instruction data
vec![], // No accounts needed
);
// Add the instruction to new transaction
let mut transaction = Transaction::new_with_payer(&[instruction], Some(&payer.pubkey()));
transaction.sign(&[&payer], client.get_latest_blockhash().unwrap());
// Send and confirm the transaction
match client.send_and_confirm_transaction(&transaction) {
Ok(signature) => println!("Transaction Signature: {}", signature),
Err(err) => eprintln!("Error sending transaction: {}", err),
}
}
Before running the script, replace the program ID in the code snippet above with the one for your program.
You can get your program ID by running the following command.
solana address -k ./target/deploy/hello_world-keypair.json
#[tokio::main]
async fn main() {
- let program_id = Pubkey::from_str("4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz").unwrap();
+ let program_id = Pubkey::from_str("YOUR_PROGRAM_ID).unwrap();
}
}
Run the client script with the following command.
cargo run --example client
Example output:
Transaction Signature: 54TWxKi3Jsi3UTeZbhLGUFX6JQH7TspRJjRRFZ8NFnwG5BXM9udxiX77bAACjKAS9fGnVeEazrXL4SfKrW7xZFYV
You can inspect the transaction signature on Solana Explorer (local cluster) to see "Hello, world!" in the program log.
Update the Program #
Solana programs can be updated by redeploying to the same program ID. Update the
program in src/lib.rs
to print "Hello, Solana!" instead of "Hello, world!".
pub fn process_instruction(
_program_id: &Pubkey,
_accounts: &[AccountInfo],
_instruction_data: &[u8],
) -> ProgramResult {
- msg!("Hello, world!");
+ msg!("Hello, Solana!");
Ok(())
}
Test the updated program by running the cargo test-sbf
command.
cargo test-sbf
You should see "Hello, Solana!" in the program log.
running 1 test
[2024-10-23T19:28:28.842639000Z INFO solana_program_test] "hello_world" SBF program from /code/misc/delete/hello_world/target/deploy/hello_world.so, modified 4 minutes, 31 seconds, 435 ms, 566 µs and 766 ns ago
[2024-10-23T19:28:28.934854000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM invoke [1]
[2024-10-23T19:28:28.936735000Z DEBUG solana_runtime::message_processor::stable_log] Program log: Hello, Solana!
[2024-10-23T19:28:28.938774000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM consumed 140 of 200000 compute units
[2024-10-23T19:28:28.938793000Z DEBUG solana_runtime::message_processor::stable_log] Program 1111111QLbz7JHiBTspS962RLKV8GndWFwiEaqKM success
test test::test_hello_world ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.14s
Run the cargo build-sbf
command to generate an updated .so
file.
cargo build-sbf
Redeploy the program using the solana program deploy
command.
solana program deploy ./target/deploy/hello_world.so
Run the client code again and inspect the transaction signature on Solana Explorer to see "Hello, Solana!" in the program log.
cargo run --example client
Close the Program #
You can close your Solana program to reclaim the SOL allocated to the account. Closing a program is irreversible, so it should be done with caution.
To close a program, use the solana program close <PROGRAM_ID>
command. For
example:
solana program close 4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz
--bypass-warning
Example output:
Closed Program Id 4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz, 0.1350588 SOL
reclaimed
Note that once a program is closed, its program ID cannot be reused. Attempting to deploy a program with a previously closed program ID will result in an error.
Error: Program 4Ujf5fXfLx2PAwRqcECCLtgDxHKPznoJpa43jUBxFfMz has been closed, use
a new Program Id
If you need to redeploy a program with the same source code after closing a program, you must generate a new program ID. To generate a new keypair for the program, run the following command:
solana-keygen new -o ./target/deploy/hello_world-keypair.json --force
Alternatively, you can delete the existing keypair file (e.g.
./target/deploy/hello_world-keypair.json
) and run cargo build-sbf
again,
which will generate a new keypair file.