Adding New Signers to Kora

Architecture Overview

Kora uses the external solana-keychain crate for all signing operations. This architecture provides a unified signing interface for signing Solana transactions. To add a new signer to Kora, you'll need to:

First: Add your signer implementation to the solana-keychain crate
Second: Add configuration support for your signer in Kora

Step-by-Step Integration Guide

Quick Integration Checklist

Part 1: Add Signer to solana-keychain Crate

Implement your signer following the solana-keychain integration guide
Wait for PR approval and crate publication

Part 2: Add Kora Configuration Support

Add Signer Support in Kora

First, ensure your signer is supported in the solana-keychain crate. If it is not, follow the guide at: https://github.com/solana-foundation/solana-keychain/blob/main/docs/ADDING_SIGNERS.md

Step 1: Update Cargo.toml

Update Cargo.toml's dependency so that solana-keychain crate uses the latest version (that includes your signer):

[dependencies]
solana-keychain = { version = "X.Y.Z", default-features = false, features = [
    "all",
    "sdk-v3",
] }

Step 2: Define Your Configuration Struct

In crates/lib/src/signer/config.rs, add a new configuration struct for your signer that defines which environment variables are needed. For example:

/// YourService signer configuration
#[derive(Clone, Serialize, Deserialize)]
pub struct YourServiceSignerConfig {
    pub api_key_env: String,
    pub api_secret_env: String,
    pub wallet_id_env: String,
}

Step 2: Add Your Signer to `SignerTypeConfig` Enum

Add your signer variant to the SignerTypeConfig enum in crates/lib/src/signer/config.rs:

/// Signer type-specific configuration
#[derive(Clone, Serialize, Deserialize)]
#[serde(tag = "type", rename_all = "snake_case")]
pub enum SignerTypeConfig {
    // Existing signer variants
    Memory { #[serde(flatten)] config: MemorySignerConfig },
    // ... existing variants ...

    // Add your signer here
    YourService {
        #[serde(flatten)]
        config: YourServiceSignerConfig,
    },
}

Step 3: Add Build Logic

In the same file (config.rs), add a method to build your signer from configuration in the SignerConfig implementation:

impl SignerConfig {
    pub async fn build_signer_from_config(config: &SignerConfig) -> Result<Signer, KoraError> {
        match &config.config {
            // ... existing cases

            SignerTypeConfig::YourService { config: your_service_config } => {
                Self::build_your_service_signer(your_service_config, &config.name).await
            }
        }
    }

    // Add this new method
    async fn build_your_service_signer(
        config: &YourServiceSignerConfig,
        signer_name: &str,
    ) -> Result<Signer, KoraError> {
        // Update the environment variable names to match your signer's configuration
        let api_key = get_env_var_for_signer(&config.api_key_env, signer_name)?;
        let api_secret = get_env_var_for_signer(&config.api_secret_env, signer_name)?;
        let wallet_id = get_env_var_for_signer(&config.wallet_id_env, signer_name)?;

        // Call the constructor from solana-keychain crate
        Signer::from_your_service(api_key, api_secret, wallet_id)
            .await
            .map_err(|e| {
                KoraError::SigningError(format!(
                    "Failed to create YourService signer '{signer_name}': {}",
                    sanitize_error!(e)
                ))
            })
    }
}

Note: The method name Signer::from_your_service() should match what you implemented in the solana-keychain crate.

Step 4: Add Validation Logic

Add validation for your signer's configuration in the validate_individual_signer_config method:

impl SignerConfig {
    pub fn validate_individual_signer_config(&self, index: usize) -> Result<(), KoraError> {
        // ... existing validation

        match &self.config {
            // ... existing cases

            SignerTypeConfig::YourService { config } => {
                Self::validate_your_service_config(config, &self.name)
            }
        }
    }

    // Add this new validation method
    fn validate_your_service_config(
        config: &YourServiceSignerConfig,
        signer_name: &str,
    ) -> Result<(), KoraError> {
        // Update the environment variable names to match your signer's configuration
        let env_vars = [
            ("api_key_env", &config.api_key_env),
            ("api_secret_env", &config.api_secret_env),
            ("wallet_id_env", &config.wallet_id_env),
        ];

        for (field_name, env_var) in env_vars {
            if env_var.is_empty() {
                return Err(KoraError::ValidationError(format!(
                    "YourService signer '{signer_name}' must specify non-empty {field_name}"
                )));
            }
        }
        Ok(())
    }
}

Step 5: Export Your Configuration

Add your new config struct to the module exports in crates/lib/src/signer/mod.rs (or at the top of the file if it's public):

pub use config::{
    MemorySignerConfig,
    PrivySignerConfig,
    SignerTypeConfig,
    TurnkeySignerConfig,
    VaultSignerConfig,
    YourServiceSignerConfig,  // Add this
    // ... other exports
};

Testing Your Integration

Add Test Mock Builder

To make testing easier, add a builder method to SignerPoolConfigBuilder in crates/lib/src/tests/config_mock.rs:

impl SignerPoolConfigBuilder {
    // ... existing methods

    pub fn with_your_service_signer(
        mut self,
        name: String,
        api_key_env: String,
        api_secret_env: String,
        wallet_id_env: String,
        weight: Option<u32>,
    ) -> Self {
        let signer = SignerConfig {
            name,
            weight,
            config: SignerTypeConfig::YourService {
                config: YourServiceSignerConfig {
                    api_key_env,
                    api_secret_env,
                    wallet_id_env,
                },
            },
        };
        self.config.signers.push(signer);
        self
    }
}

This allows other tests to easily create mock configurations that include your signer:

use crate::tests::config_mock::SignerPoolConfigBuilder;

let config = SignerPoolConfigBuilder::new()
    .with_your_service_signer(
        "yourservice_test".to_string(),
        "YOUR_SERVICE_API_KEY".to_string(),
        "YOUR_SERVICE_API_SECRET".to_string(),
        "YOUR_SERVICE_WALLET_ID".to_string(),
        Some(1)
    )
    .build();

Environment Variables

Add the example environment variables to the following files:

.env.example (root of the project)
.env (root of the project, for local testing)
./sdks/ts/.env.example
./sdks/ts/.env

# YourService Signer Configuration
YOUR_SERVICE_API_KEY=your_api_key_here
YOUR_SERVICE_API_SECRET=your_api_secret_here
YOUR_SERVICE_WALLET_ID=your_wallet_id_here

Integration Tests

Kora uses a unified test runner (tests/src/bin/test_runner.rs) that manages all integration testing phases including TypeScript tests. To add tests for your new signer:

1. Add Test Configuration

Create a new signer configuration file in tests/src/common/fixtures/ for your service:

# tests/src/common/fixtures/signers-your-service.toml
[signer_pool]
strategy = "round_robin"

[[signers]]
name = "yourservice_main"
type = "your_service"
api_key_env = "YOUR_SERVICE_API_KEY"
api_secret_env = "YOUR_SERVICE_API_SECRET"
wallet_id_env = "YOUR_SERVICE_WALLET_ID"

2. Add Test Phase to Test Runner

Update tests/src/test_runner/test_cases.toml to include a test phase for your signer:

[test.your_service]
name = "YourService Signer Tests"
config = "tests/src/common/fixtures/kora-test.toml"
signers = "tests/src/common/fixtures/signers-your-service.toml"
port = "8090"  # Use a unique port
tests = ["your_service"]

3. Running Tests

Make sure your environment is set up:

# Install binaries and dependencies
just install
just install-ts-sdk
just build-ts-sdk

# Set environment variables for your service
export YOUR_SERVICE_API_KEY="your_key"
export YOUR_SERVICE_API_SECRET="your_secret"
export YOUR_SERVICE_WALLET_ID="your_wallet"

Run tests using the unified test runner:

# Run all integration tests (includes your new signer phase)
just test-integration

# Run tests with verbose output
just test-integration-verbose

# Run specific test phase with filter
cargo run -p tests --bin test_runner -- --phases your_service

Documentation Requirements

When submitting your PR, include:

1. Update the Signers Guide

Add signer documentation following the ADDING_SIGNERS.md guide, explaining the prerequisites, setup, and usage.

## YourService Signer

[YourService](https://yourservice.com) provides [brief description of your
service].

### Prerequisites

- YourService account
- API credentials
- Funded wallet

### Setup

1. Get your API credentials from [dashboard link]
2. Create a wallet...
3. Configure environment variables:

\```bash YOUR_SERVICE_API_KEY="your_api_key"
YOUR_SERVICE_API_SECRET="your_api_secret"
YOUR_SERVICE_WALLET_ID="your_wallet_id" \```

### Configure signers.toml

\```toml [signer_pool] strategy = "round_robin"

[[signers]] name = "yourservice_main" type = "your_service" api_key_env =
"YOUR_SERVICE_API_KEY" api_secret_env = "YOUR_SERVICE_API_SECRET" wallet_id_env
= "YOUR_SERVICE_WALLET_ID" weight = 1 \```

### Run Kora with YourService Signer

\```bash kora rpc start --signers-config signers.toml \```

For signer implementation: Open an issue in the solana-keychain repository
For Kora integration: Open an issue in the Kora repository for design discussions
Join our community channels
Review existing signer configurations in crates/lib/src/signer/config.rs

Example PR Structure

For Kora repository:

feat(signer): add YourService signer configuration support

- Add YourServiceSignerConfig struct
- Add YourService variant to SignerTypeConfig enum
- Add build and validation logic for YourService
- Add example configuration files
- Add documentation to SIGNERS.md
- Add integration tests

Welcome to the Kora ecosystem! We're excited to have your key management solution as part of the platform.