fix: use split transaction for escrow settlement to avoid rent issues

- Settlement now sends beneficiary + fee in single atomic transaction
- Avoids insufficient rent error on small SOL escrows
- Falls back to sequential sends if split unavailable
- Added sendSplitTransaction to BlockchainProvider interface
- Added tests for settlement logic
- Bump to v0.4.14

Author: ralyodio

package.json

@@ -1,6 +1,6 @@
 {
   "name": "coinpayportal",
-  "version": "0.4.13",
+  "version": "0.4.14",
   "private": true,
   "type": "module",
   "bin": {

packages/sdk/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@profullstack/coinpay",
-  "version": "0.4.13",
+  "version": "0.4.14",
   "description": "CoinPay SDK & CLI — Accept cryptocurrency payments (BTC, ETH, SOL, POL, BCH, USDC) with wallet and swap support",
   "type": "module",
   "main": "./src/index.js",

src/app/api/escrow/[id]/settle/route.test.ts

@@ -0,0 +1,79 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+
+/**
+ * Tests for escrow settlement route logic.
+ * Verifies that split transactions are preferred for release+fee scenarios.
+ */
+
+describe('Escrow Settlement Logic', () => {
+  it('should use split transaction when releasing with fee', () => {
+    const action = 'release';
+    const feeAmount = 0.001;
+    const hasSplitTx = true;
+    const commissionWallet = 'CommissionWallet123';
+
+    const useSplit = action === 'release' && feeAmount > 0 && hasSplitTx && !!commissionWallet;
+    expect(useSplit).toBe(true);
+  });
+
+  it('should NOT use split transaction for refunds', () => {
+    const action = 'refund';
+    const feeAmount = 0.001;
+    const hasSplitTx = true;
+    const commissionWallet = 'CommissionWallet123';
+
+    const useSplit = action === 'release' && feeAmount > 0 && hasSplitTx && !!commissionWallet;
+    expect(useSplit).toBe(false);
+  });
+
+  it('should NOT use split transaction when no commission wallet', () => {
+    const action = 'release';
+    const feeAmount = 0.001;
+    const hasSplitTx = true;
+    const commissionWallet = null;
+
+    const useSplit = action === 'release' && feeAmount > 0 && hasSplitTx && !!commissionWallet;
+    expect(useSplit).toBe(false);
+  });
+
+  it('should NOT use split transaction when fee is 0', () => {
+    const action = 'release';
+    const feeAmount = 0;
+    const hasSplitTx = true;
+    const commissionWallet = 'CommissionWallet123';
+
+    const useSplit = action === 'release' && feeAmount > 0 && hasSplitTx && !!commissionWallet;
+    expect(useSplit).toBe(false);
+  });
+
+  it('should fall back to sequential when provider lacks sendSplitTransaction', () => {
+    const action = 'release';
+    const feeAmount = 0.001;
+    const hasSplitTx = false;
+    const commissionWallet = 'CommissionWallet123';
+
+    const useSplit = action === 'release' && feeAmount > 0 && hasSplitTx && !!commissionWallet;
+    expect(useSplit).toBe(false);
+  });
+
+  it('should calculate correct amounts for beneficiary and fee', () => {
+    const depositedAmount = 0.011896577;
+    const feeAmount = 0.000118965765629796;
+    const amountToSend = depositedAmount - feeAmount;
+
+    expect(amountToSend).toBeCloseTo(0.011777611, 8);
+    expect(amountToSend + feeAmount).toBeCloseTo(depositedAmount, 8);
+  });
+
+  it('should send full deposited amount on refund (no fee)', () => {
+    const depositedAmount = 0.011896577;
+    const feeAmount = 0.000118965765629796;
+    const action = 'refund';
+
+    const amountToSend = action === 'refund'
+      ? depositedAmount
+      : depositedAmount - feeAmount;
+
+    expect(amountToSend).toBe(depositedAmount);
+  });
+});

src/app/api/escrow/[id]/settle/route.ts

@@ -120,9 +120,38 @@ export async function POST(
     let txHash: string | undefined;
     let feeTxHash: string | undefined;
 
-    if (provider.sendTransaction) {
-      // Forward to destination (beneficiary or depositor)
-      // sendTransaction signature: (from, to, amount, privateKey) → string
+    if (!provider.sendTransaction) {
+      return NextResponse.json(
+        { error: `No transaction provider for chain ${escrow.chain}` },
+        { status: 500 }
+      );
+    }
+
+    // Use split transaction when releasing with fee — single atomic tx
+    // This avoids rent/balance issues from sequential sends
+    if (action === 'release' && escrow.fee_amount > 0 && provider.sendSplitTransaction && addressData.commission_wallet) {
+      try {
+        const recipients = [
+          { address: destinationAddress, amount: String(amountToSend) },
+          { address: addressData.commission_wallet, amount: String(escrow.fee_amount) },
+        ];
+        console.log(`[Settle] Using split transaction for escrow ${escrowId}: ${JSON.stringify(recipients)}`);
+        txHash = await provider.sendSplitTransaction(
+          addressData.address,
+          recipients,
+          privateKey
+        );
+        // Both beneficiary and fee are in the same tx
+        feeTxHash = txHash;
+      } catch (splitError) {
+        console.error(`Split transaction failed for escrow ${escrowId}, falling back to sequential:`, splitError);
+        // Fall back to sequential sends
+        txHash = undefined;
+      }
+    }
+
+    // Fallback: sequential sends (refunds, or if split failed, or no commission)
+    if (!txHash) {
       txHash = await provider.sendTransaction(
         addressData.address,
         destinationAddress,
@@ -131,7 +160,7 @@ export async function POST(
       );
 
       // If release (not refund), also send platform fee to commission wallet
-      if (action === 'release' && escrow.fee_amount > 0) {
+      if (action === 'release' && escrow.fee_amount > 0 && addressData.commission_wallet) {
         try {
           feeTxHash = await provider.sendTransaction(
             addressData.address,
@@ -144,11 +173,6 @@ export async function POST(
           // Non-fatal — main settlement still succeeded
         }
       }
-    } else {
-      return NextResponse.json(
-        { error: `No transaction provider for chain ${escrow.chain}` },
-        { status: 500 }
-      );
     }
 
     // Mark as settled

src/lib/blockchain/providers.ts

@@ -51,6 +51,7 @@ export interface BlockchainProvider {
   getTransaction(txHash: string): Promise<TransactionDetails>;
   getRequiredConfirmations(): number;
   sendTransaction?(from: string, to: string, amount: string, privateKey: string): Promise<string>;
+  sendSplitTransaction?(from: string, recipients: Array<{ address: string; amount: string }>, privateKey: string): Promise<string>;
 }
 
 /**