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name: debridge creator: raunit-dev description: Complete deBridge Protocol SDK for building cross-chain bridges, message passing, and token transfers on Solana. Use when building cross-chain applications, bridging assets between Solana and EVM chains, or implementing trustless external calls.

deBridge Solana SDK Development Guide

A comprehensive guide for building Solana programs with the deBridge Solana SDK - enabling decentralized cross-chain transfers of arbitrary messages and value between blockchains.

Overview

deBridge is a cross-chain infrastructure protocol enabling:

• Cross-Chain Transfers: Bridge assets between Solana and 20+ EVM chains
• Message Passing: Send arbitrary messages across blockchains
• External Calls: Execute smart contract calls on destination chains
• Sub-Second Settlement: ~2 second median settlement time
• Capital Efficiency: Intent-based architecture with 4bps lowest spreads

Key Features

• 26+ security audits (Halborn, Zokyo, Ackee Blockchain)
• $200K bug bounty on Immunefi
• 100% uptime since launch
• Zero security incidents

Quick Start

Installation

Add the SDK to your Anchor/Solana program:

cargo add --git ssh://git@github.com/debridge-finance/debridge-solana-sdk.git debridge-solana-sdk

Or add to Cargo.toml:

[dependencies]
debridge-solana-sdk = { git = "ssh://git@github.com/debridge-finance/debridge-solana-sdk.git" }

Basic Setup (Anchor)

use anchor_lang::prelude::*;
use debridge_solana_sdk::prelude::*;

declare_id!("YourProgramId11111111111111111111111111111");

#[program]
pub mod my_bridge_program {
    use super::*;

    pub fn send_cross_chain(
        ctx: Context<SendCrossChain>,
        target_chain_id: [u8; 32],
        receiver: Vec<u8>,
        amount: u64,
    ) -> Result<()> {
        // Invoke deBridge send
        debridge_sending::invoke_debridge_send(
            debridge_sending::SendIx {
                target_chain_id,
                receiver,
                is_use_asset_fee: false,  // Use native SOL for fees
                amount,
                submission_params: None,
                referral_code: None,
            },
            ctx.remaining_accounts,
        )?;

        Ok(())
    }
}

#[derive(Accounts)]
pub struct SendCrossChain<'info> {
    #[account(mut)]
    pub sender: Signer<'info>,
    // Additional accounts passed via remaining_accounts
}

Core Concepts

1. Chain IDs

deBridge uses 32-byte chain identifiers for all supported networks:

use debridge_solana_sdk::chain_ids::*;

// Solana
let solana = SOLANA_CHAIN_ID;  // Solana mainnet

// EVM Chains
let ethereum = ETHEREUM_CHAIN_ID;     // Chain ID: 1
let polygon = POLYGON_CHAIN_ID;       // Chain ID: 137
let bnb = BNB_CHAIN_CHAIN_ID;         // Chain ID: 56
let arbitrum = ARBITRUM_CHAIN_ID;     // Chain ID: 42161
let avalanche = AVALANCHE_CHAIN_ID;   // Chain ID: 43114
let fantom = FANTOM_CHAIN_ID;         // Chain ID: 250
let heco = HECO_CHAIN_ID;             // Chain ID: 128

2. Program IDs

use debridge_solana_sdk::{DEBRIDGE_ID, SETTINGS_ID};

// Main deBridge program for sending/claiming
let debridge_program = DEBRIDGE_ID;

// Settings and confirmation storage program
let settings_program = SETTINGS_ID;

3. Fee Structure

deBridge supports multiple fee payment methods:

// Native Fee (SOL)
is_use_asset_fee: false  // Pay fees in SOL

// Asset Fee
is_use_asset_fee: true   // Pay fees in the bridged token

// Fee Constants
const BPS_DENOMINATOR: u64 = 10000;  // Basis points divisor

4. Flags

Control transfer behavior with flags:

use debridge_solana_sdk::flags::*;

// Available flags (bit positions)
const UNWRAP_ETH: u8 = 0;              // Unwrap to native ETH on destination
const REVERT_IF_EXTERNAL_FAIL: u8 = 1; // Revert if external call fails
const PROXY_WITH_SENDER: u8 = 2;       // Include sender in proxy call
const SEND_HASHED_DATA: u8 = 3;        // Send data as hash
const DIRECT_WALLET_FLOW: u8 = 31;     // Use direct wallet flow

// Setting flags on submission params
let mut flags = [0u8; 32];
flags.set_reserved_flag(UNWRAP_ETH);
flags.set_reserved_flag(REVERT_IF_EXTERNAL_FAIL);

Sending Cross-Chain Transfers

Basic Token Transfer

use debridge_solana_sdk::prelude::*;

pub fn send_tokens(
    ctx: Context<SendTokens>,
    amount: u64,
) -> Result<()> {
    debridge_sending::invoke_debridge_send(
        debridge_sending::SendIx {
            target_chain_id: chain_ids::ETHEREUM_CHAIN_ID,
            receiver: recipient_eth_address.to_vec(),
            is_use_asset_fee: false,
            amount,
            submission_params: None,
            referral_code: Some(12345),  // Optional referral
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Transfer with Fixed Native Fee

pub fn send_with_native_fee(
    ctx: Context<Send>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,
    amount: u64,
) -> Result<()> {
    // Get the fixed fee for the target chain
    let fee = debridge_sending::get_chain_native_fix_fee(
        &target_chain_id,
        ctx.remaining_accounts,
    )?;

    debridge_sending::invoke_debridge_send(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: false,
            amount,
            submission_params: None,
            referral_code: None,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Transfer with Asset Fee

pub fn send_with_asset_fee(
    ctx: Context<Send>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,
    amount: u64,
) -> Result<()> {
    // Check if asset fee is available for this chain
    let is_available = debridge_sending::is_asset_fee_available(
        &target_chain_id,
        ctx.remaining_accounts,
    )?;

    if !is_available {
        return Err(error!(ErrorCode::AssetFeeNotAvailable));
    }

    debridge_sending::invoke_debridge_send(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: true,  // Use asset for fees
            amount,
            submission_params: None,
            referral_code: None,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Transfer with Exact Amount

pub fn send_exact_amount(
    ctx: Context<Send>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,
    exact_receive_amount: u64,
) -> Result<()> {
    // Calculate total amount including fees
    let total_with_fees = debridge_sending::add_all_fees(
        exact_receive_amount,
        &target_chain_id,
        ctx.remaining_accounts,
    )?;

    debridge_sending::invoke_debridge_send(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: true,
            amount: total_with_fees,
            submission_params: None,
            referral_code: None,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Transfer from PDA (Signed)

pub fn send_from_pda(
    ctx: Context<SendFromPda>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,
    amount: u64,
    pda_seeds: Vec<Vec<u8>>,
) -> Result<()> {
    // Use signed variant for PDA-owned tokens
    debridge_sending::invoke_debridge_send_signed(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: false,
            amount,
            submission_params: None,
            referral_code: None,
        },
        ctx.remaining_accounts,
        &pda_seeds,
    )?;

    Ok(())
}

Message Passing

Send messages without token transfers:

use debridge_solana_sdk::prelude::*;

pub fn send_message(
    ctx: Context<SendMessage>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,
    message_data: Vec<u8>,
) -> Result<()> {
    // Create submission params with message
    let submission_params = debridge_sending::SendSubmissionParamsInput {
        execution_fee: 0,
        flags: [0u8; 32],
        fallback_address: receiver.clone(),
        external_call_shortcut: compute_keccak256(&message_data),
    };

    // Send message (zero amount)
    debridge_sending::invoke_send_message(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: false,
            amount: 0,  // No token transfer
            submission_params: Some(submission_params),
            referral_code: None,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

External Calls

Execute smart contract calls on destination chains:

Initialize External Call Buffer

pub fn init_external_call(
    ctx: Context<InitExternalCall>,
    target_chain_id: [u8; 32],
    external_call_data: Vec<u8>,
) -> Result<()> {
    let shortcut = compute_keccak256(&external_call_data);

    debridge_sending::invoke_init_external_call(
        debridge_sending::InitExternalCallIx {
            external_call_len: external_call_data.len() as u32,
            chain_id: target_chain_id,
            external_call_shortcut: shortcut,
            external_call: external_call_data,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Send with External Call

pub fn send_with_external_call(
    ctx: Context<SendWithExternalCall>,
    target_chain_id: [u8; 32],
    receiver: Vec<u8>,  // Target contract address
    amount: u64,
    external_call_data: Vec<u8>,
    execution_fee: u64,  // Fee for executor on destination
) -> Result<()> {
    let shortcut = compute_keccak256(&external_call_data);

    // Set flags for external call behavior
    let mut flags = [0u8; 32];
    flags.set_reserved_flag(flags::REVERT_IF_EXTERNAL_FAIL);

    let submission_params = debridge_sending::SendSubmissionParamsInput {
        execution_fee,
        flags,
        fallback_address: ctx.accounts.fallback.key().to_bytes().to_vec(),
        external_call_shortcut: shortcut,
    };

    debridge_sending::invoke_debridge_send(
        debridge_sending::SendIx {
            target_chain_id,
            receiver,
            is_use_asset_fee: false,
            amount,
            submission_params: Some(submission_params),
            referral_code: None,
        },
        ctx.remaining_accounts,
    )?;

    Ok(())
}

Claim Verification

Verify claims on the receiving side:

Validate Incoming Claims

use debridge_solana_sdk::check_claiming::*;

pub fn receive_tokens(ctx: Context<ReceiveTokens>) -> Result<()> {
    // Get and validate the parent claim instruction
    let claim_ix = ValidatedExecuteExtCallIx::try_from_current_ix()?;

    // Validate submission details
    let validation = SubmissionAccountValidation {
        receiver_validation: Some(ctx.accounts.receiver.key()),
        token_mint_validation: Some(ctx.accounts.token_mint.key()),
        source_chain_id_validation: Some(chain_ids::ETHEREUM_CHAIN_ID),
        ..Default::default()
    };

    claim_ix.validate_submission_account(
        &ctx.accounts.submission_account,
        &validation,
    )?;

    // Proceed with claim logic
    Ok(())
}

Get Submission Key

pub fn get_claim_info(ctx: Context<ClaimInfo>) -> Result<Pubkey> {
    let claim_ix = ValidatedExecuteExtCallIx::try_from_current_ix()?;
    let submission_key = claim_ix.get_submission_key()?;
    Ok(submission_key)
}

Fee Queries

Get Transfer Fees

// Get base transfer fee (in BPS)
let transfer_fee = debridge_sending::get_transfer_fee(
    ctx.remaining_accounts,
)?;

// Get transfer fee for specific chain
let chain_fee = debridge_sending::get_transfer_fee_for_chain(
    &target_chain_id,
    ctx.remaining_accounts,
)?;

// Get default native fix fee
let default_fee = debridge_sending::get_default_native_fix_fee(
    ctx.remaining_accounts,
)?;

// Get chain-specific native fix fe