How to Set Up a Solana Transaction Sender with Syncro Sender

Introduction

If your execution depends on transaction landing, set up speed matters.

Syncro Sender is designed to integrate directly into your existing flow with minimal changes. You can start sending transactions in minutes using either a public or a private endpoint.

This guide walks through how to set up Syncro Sender and start sending transactions immediately. For a full technical reference, see the Syncro Sender documentation.

What You Need Before Starting

Before using Syncro Sender, make sure you have:

• A signed Solana transaction
• Base64 encoded transaction data
• A standard RPC endpoint for reads such as blockhash and confirmation

Syncro Sender is used for transaction delivery, not simulation or state queries.

Step 1: Choose Your Endpoint

Syncro Sender supports two access modes.

Public endpoint (no API key)

• No authentication required
• Requires a tip of 0.0001 SOL (100,000 lamports) inside the transaction
• Rate limited to 1 request per second
• Best for quick testing

Available endpoints:

• Frankfurt: http://sfls-geo-fra.l2.p2p.org/public
• New York: http://sfls-geo-nyc.l2.p2p.org/public
• London: http://sfls-geo-lon.l2.p2p.org/public
• Tokyo: http://sfls-geo-tky.l2.p2p.org/public
• Singapore: http://sfls-geo-sgp.l2.p2p.org/public
• Amsterdam: http://sfls-eu1.l2.p2p.org/public

Private endpoint (API key)

• Requires API key authentication
• Requires a tip of 0.001 SOL (1,000,000 lamports). For the first month, the tip is reduced to 0.0001 SOL as part of the production benchmark period
• Supports up to 50 requests per second
• Supports full RPC methods

To get access, request it via the Syncro Sender page or contact the team.

Step 2: Add a Tip to Your Transaction

A tip is required for both public and private endpoints.

Minimum tip

• Public: 100,000 lamports (0.0001 SOL)
• Private: 1,000,000 lamports (0.001 SOL)

How to add the tip

Add a System Program transfer instruction to a valid tip account:

transaction.addInstruction(
SystemProgram.transfer(
yourPublicKey,
'BPZrtYhdoAhiHWV5EgGLoV7bZFbMamBZurGDq4DmST8v',
100000
)
);transaction.addInstruction(
  SystemProgram.transfer(
    yourPublicKey,
    'BPZrtYhdoAhiHWV5EgGLoV7bZFbMamBZurGDq4DmST8v',
    100000
  )
);

Common errors

• Missing tip → request fails
• Insufficient tip → request fails

Error example:

"Insufficient tip: provided X lamports, required Y lamports"

Step 3: Send Your Transaction

Public endpoint request

curl -X POST <https://sfls.l2.p2p.org/public> \\
  -H "Content-Type: application/json" \\
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "sendTransaction",
    "params": ["<BASE64_ENCODED_TX_WITH_TIP>", {"encoding": "base64"}]
  }'

Private endpoint request

curl -X POST <https://sfls.l2.p2p.org> \\
  -H "Content-Type: application/json" \\
  -H "Authorization: Bearer YOUR_API_KEY" \\
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "sendTransaction",
    "params": ["<BASE64_ENCODED_TX>", {"encoding": "base64"}]
  }'

Response

{
  "jsonrpc": "2.0",
  "result": "<TRANSACTION_SIGNATURE>",
  "id": 1
}

Step 4: Test and Compare Performance

Once integrated, test Syncro Sender alongside your current setup.

Focus on:

• landing success rate
• time to confirmation
• consistency under load

Use your standard RPC to monitor transaction status. Private endpoint users can also use Syncro Sender for all standard Solana RPC requests, including status checks and confirmation queries.

Performance Best Practices

To get the best results:

• Use skipPreflight: true to reduce latency
• Use base64 encoding
• Reuse HTTP connections with keep alive
• Add a priority fee for validator scheduling

Retry strategy

• 429 → wait and retry
• 500 → retry with backoff
• 400 → fix request
• network error → retry

Submitting the same transaction multiple times is safe.

Common Mistakes to Avoid

• Sending transactions without a tip
• Using Syncro Sender for read requests on the public endpoint
• Not adding priority fees for competitive execution
• Opening new connections for every request
• Ignoring rate limit headers

When to Use Public vs Private

Use case	Recommendation
Testing	Public endpoint
Production trading	Private endpoint
High frequency workflows	Private endpoint

What This Setup Actually Changes

Syncro Sender does not change your transaction logic.

It changes how your transactions are delivered.

That means:

• better routing
• higher landing probability
• more consistent execution

Get Started

You can start immediately using the public endpoint.

For production use cases, request access to the private endpoint.

For the full technical reference and advanced configuration options, visit the Syncro Sender documentation.

👉 Syncro Sender: https://www.p2p.org/products/syncro-solana-transaction-sender
👉 Docs: https://docs.p2p.org/docs/syncro-sender-overview

FAQ

Do I need an API key to use Syncro Sender?

No. The public endpoint requires only a tip of 0.0001 SOL in the transaction.

What happens if I do not include a tip?

The transaction will be rejected with an error.

Can I use Syncro Sender for read requests?

Only on private endpoints with this feature enabled.

How do I check if my transaction landed?

Use a standard Solana RPC method such as getSignatureStatuses.

What encoding should I use?

Base64 encoding is required and recommended.