diff --git a/test/sync-live-fallback.test.js b/test/sync-live-fallback.test.js
new file mode 100644
index 0000000..fda50db
--- /dev/null
+++ b/test/sync-live-fallback.test.js
@@ -0,0 +1,118 @@
+#!/usr/bin/env bun
+/**
+ * Live Sync Fallback Test
+ *
+ * Tests the JSON fallback path by disabling binary endpoint.
+ * Compares performance against binary path.
+ *
+ * Usage:
+ *   bun test/sync-live-fallback.test.js [--daemon URL] [--start HEIGHT] [--blocks N]
+ */
+
+import { WalletSync, SYNC_STATUS, DEFAULT_BATCH_SIZE } from '../src/wallet-sync.js';
+import { MemoryStorage } from '../src/wallet-store.js';
+import { DaemonRPC } from '../src/rpc/daemon.js';
+import { randomScalar, scalarMultBase } from '../src/crypto/index.js';
+import { bytesToHex } from '../src/address.js';
+
+const args = process.argv.slice(2);
+function getArg(name, fallback) {
+  const idx = args.indexOf(name);
+  return idx >= 0 && idx + 1 < args.length ? args[idx + 1] : fallback;
+}
+
+const DAEMON_URL = getArg('--daemon', 'http://core2.whiskymine.io:19081');
+const START_HEIGHT = parseInt(getArg('--start', '1000'), 10);
+const BLOCK_COUNT = parseInt(getArg('--blocks', '100'), 10);
+
+function generateTestKeys() {
+  const viewSec = randomScalar();
+  const spendSec = randomScalar();
+  const spendPub = scalarMultBase(spendSec);
+  return {
+    viewSecretKey: bytesToHex(viewSec),
+    spendSecretKey: bytesToHex(spendSec),
+    spendPublicKey: bytesToHex(spendPub),
+  };
+}
+
+async function runSync(daemon, label) {
+  const storage = new MemoryStorage();
+  await storage.open();
+  await storage.setSyncHeight(START_HEIGHT);
+
+  const keys = generateTestKeys();
+  const sync = new WalletSync({ storage, daemon, keys, batchSize: DEFAULT_BATCH_SIZE });
+
+  const stats = { batches: 0, blocks: 0, batchSizes: [] };
+
+  sync.on('newBlock', () => { stats.blocks++; });
+  sync.on('batchComplete', (data) => {
+    stats.batches++;
+    stats.batchSizes.push(data.batchSize);
+  });
+
+  const targetHeight = START_HEIGHT + BLOCK_COUNT;
+  const origGetInfo = daemon.getInfo.bind(daemon);
+  daemon.getInfo = async () => {
+    const r = await origGetInfo();
+    if (r.success) r.result.height = targetHeight;
+    return r;
+  };
+
+  const t0 = Date.now();
+  try {
+    await sync.start(START_HEIGHT);
+  } catch (e) {
+    console.error(`  [${label}] Sync failed: ${e.message}`);
+  }
+  const elapsed = Date.now() - t0;
+
+  // Restore getInfo
+  daemon.getInfo = origGetInfo;
+
+  console.log(`  [${label}] ${stats.blocks} blocks in ${(elapsed / 1000).toFixed(2)}s (${(stats.blocks / (elapsed / 1000)).toFixed(1)} blocks/sec)`);
+  console.log(`  [${label}] ${stats.batches} batches, sizes: [${stats.batchSizes.join(', ')}]`);
+  console.log(`  [${label}] Status: ${sync.status}`);
+
+  await storage.close();
+  return { elapsed, blocks: stats.blocks, status: sync.status };
+}
+
+async function main() {
+  console.log('=== Sync Fallback Path Comparison ===\n');
+  console.log(`Daemon:  ${DAEMON_URL}`);
+  console.log(`Range:   ${START_HEIGHT} → ${START_HEIGHT + BLOCK_COUNT}\n`);
+
+  const daemon = new DaemonRPC({ url: DAEMON_URL, timeout: 30000 });
+  const info = await daemon.getInfo();
+  if (!info.success) {
+    console.error('Failed to connect:', info.error);
+    process.exit(1);
+  }
+  console.log(`Daemon height: ${info.result.height}\n`);
+
+  // 1. Binary path
+  console.log('--- Binary Bulk Fetch ---');
+  const binResult = await runSync(daemon, 'binary');
+
+  // 2. JSON fallback path (disable binary endpoint)
+  console.log('\n--- JSON Fallback (parallel) ---');
+  const origGetBlocksByHeight = daemon.getBlocksByHeight;
+  daemon.getBlocksByHeight = null; // Force JSON fallback
+  const jsonResult = await runSync(daemon, 'json');
+  daemon.getBlocksByHeight = origGetBlocksByHeight; // Restore
+
+  // 3. Compare
+  console.log('\n--- Comparison ---');
+  const speedup = jsonResult.elapsed / binResult.elapsed;
+  console.log(`Binary: ${(binResult.elapsed / 1000).toFixed(2)}s`);
+  console.log(`JSON:   ${(jsonResult.elapsed / 1000).toFixed(2)}s`);
+  console.log(`Binary is ${speedup.toFixed(1)}x faster`);
+
+  const pass = binResult.status === 'complete' && jsonResult.status === 'complete';
+  console.log(`\nBoth paths: ${pass ? 'PASS' : 'FAIL'}`);
+  process.exit(pass ? 0 : 1);
+}
+
+main().catch(e => { console.error('Fatal:', e); process.exit(1); });
diff --git a/test/sync-live.test.js b/test/sync-live.test.js
new file mode 100644
index 0000000..5f3039f
--- /dev/null
+++ b/test/sync-live.test.js
@@ -0,0 +1,231 @@
+#!/usr/bin/env bun
+/**
+ * Live Sync Engine Test
+ *
+ * Tests wallet-sync.js against a real Salvium daemon.
+ * Syncs a range of blocks and reports:
+ *   - Binary bulk fetch vs JSON fallback path
+ *   - Adaptive batch sizing behavior
+ *   - Throughput (blocks/sec)
+ *   - Transaction scanning (miner_tx / protocol_tx / regular)
+ *
+ * Usage:
+ *   bun test/sync-live.test.js [--daemon URL] [--start HEIGHT] [--blocks N]
+ *
+ * Defaults:
+ *   --daemon  http://core2.whiskymine.io:19081
+ *   --start   1000
+ *   --blocks  200
+ */
+
+import { WalletSync, SYNC_STATUS, DEFAULT_BATCH_SIZE } from '../src/wallet-sync.js';
+import { MemoryStorage, WalletOutput } from '../src/wallet-store.js';
+import { DaemonRPC } from '../src/rpc/daemon.js';
+import { randomScalar, scalarMultBase } from '../src/crypto/index.js';
+import { bytesToHex } from '../src/address.js';
+
+// ── CLI args ──────────────────────────────────────────────────────────────────
+const args = process.argv.slice(2);
+function getArg(name, fallback) {
+  const idx = args.indexOf(name);
+  return idx >= 0 && idx + 1 < args.length ? args[idx + 1] : fallback;
+}
+
+const DAEMON_URL = getArg('--daemon', 'http://core2.whiskymine.io:19081');
+const START_HEIGHT = parseInt(getArg('--start', '1000'), 10);
+const BLOCK_COUNT = parseInt(getArg('--blocks', '200'), 10);
+
+// ── Stats ─────────────────────────────────────────────────────────────────────
+const stats = {
+  binaryBatches: 0,
+  jsonBatches: 0,
+  batchSizes: [],
+  msPerBlock: [],
+  blocksPerSec: [],
+  events: { newBlock: 0, syncProgress: 0, batchComplete: 0 },
+  errors: [],
+  txCounts: { minerTx: 0, protocolTx: 0, regular: 0 },
+};
+
+// ── Helpers ───────────────────────────────────────────────────────────────────
+function generateTestKeys() {
+  // Generate random wallet keys for scanning (won't find outputs, but exercises the code)
+  const viewSec = randomScalar();
+  const spendSec = randomScalar();
+  const spendPub = scalarMultBase(spendSec);
+  return {
+    viewSecretKey: bytesToHex(viewSec),
+    spendSecretKey: bytesToHex(spendSec),
+    spendPublicKey: bytesToHex(spendPub),
+  };
+}
+
+// ── Main ──────────────────────────────────────────────────────────────────────
+async function main() {
+  console.log('=== Live Sync Engine Test ===\n');
+  console.log(`Daemon:  ${DAEMON_URL}`);
+  console.log(`Range:   ${START_HEIGHT} → ${START_HEIGHT + BLOCK_COUNT}`);
+  console.log(`Initial batch size: ${DEFAULT_BATCH_SIZE}\n`);
+
+  // 1. Connect to daemon
+  const daemon = new DaemonRPC({ url: DAEMON_URL, timeout: 30000 });
+  const info = await daemon.getInfo();
+  if (!info.success) {
+    console.error('Failed to connect to daemon:', info.error);
+    process.exit(1);
+  }
+  const chainHeight = info.result.height;
+  console.log(`Daemon height: ${chainHeight}`);
+  if (START_HEIGHT + BLOCK_COUNT > chainHeight) {
+    console.error(`Requested range exceeds chain height (${chainHeight}). Adjust --start or --blocks.`);
+    process.exit(1);
+  }
+
+  // 2. Quick sanity: test binary endpoint availability
+  console.log('\nTesting binary endpoint (getBlocksByHeight)...');
+  try {
+    const binTest = await daemon.getBlocksByHeight([START_HEIGHT]);
+    if (binTest.success && binTest.result.blocks?.length === 1) {
+      console.log('  Binary endpoint: AVAILABLE');
+      const blk = binTest.result.blocks[0];
+      console.log(`  Block blob size: ${blk.block?.length || blk.block?.byteLength || '?'} bytes`);
+      console.log(`  Embedded txs: ${blk.txs?.length || 0}`);
+    } else {
+      console.log('  Binary endpoint: NOT AVAILABLE (will use JSON fallback)');
+    }
+  } catch (e) {
+    console.log(`  Binary endpoint: ERROR — ${e.message}`);
+  }
+
+  // 3. Create sync engine with test wallet
+  const storage = new MemoryStorage();
+  await storage.open();
+  await storage.setSyncHeight(START_HEIGHT);
+
+  const keys = generateTestKeys();
+  const sync = new WalletSync({
+    storage,
+    daemon,
+    keys,
+    batchSize: DEFAULT_BATCH_SIZE,
+  });
+
+  // 4. Wire up events
+  sync.on('newBlock', (data) => {
+    stats.events.newBlock++;
+    if (data.hasMinerTx) stats.txCounts.minerTx++;
+    if (data.hasProtocolTx) stats.txCounts.protocolTx++;
+    stats.txCounts.regular += data.txCount || 0;
+  });
+
+  sync.on('syncProgress', (data) => {
+    stats.events.syncProgress++;
+    // Log every 50 blocks
+    if (stats.events.syncProgress % 50 === 0) {
+      console.log(`  Progress: ${data.currentHeight} / ${data.targetHeight} (${data.percentComplete.toFixed(1)}%)`);
+    }
+  });
+
+  sync.on('batchComplete', (data) => {
+    stats.events.batchComplete++;
+    stats.batchSizes.push(data.batchSize);
+    stats.msPerBlock.push(data.msPerBlock);
+    stats.blocksPerSec.push(data.blocksPerSec);
+  });
+
+  sync.on('syncError', (error) => {
+    stats.errors.push(error.message);
+  });
+
+  // Override target height so we only sync BLOCK_COUNT blocks
+  // We do this by patching daemon.getInfo to return our target
+  const originalGetInfo = daemon.getInfo.bind(daemon);
+  const targetHeight = START_HEIGHT + BLOCK_COUNT;
+  daemon.getInfo = async function () {
+    const result = await originalGetInfo();
+    if (result.success) {
+      result.result.height = targetHeight;
+    }
+    return result;
+  };
+
+  // 5. Run sync
+  console.log(`\nSyncing ${BLOCK_COUNT} blocks (${START_HEIGHT} → ${targetHeight})...\n`);
+  const syncStart = Date.now();
+
+  try {
+    await sync.start(START_HEIGHT);
+  } catch (e) {
+    console.error(`\nSync failed: ${e.message}`);
+    if (e.stack) console.error(e.stack);
+  }
+
+  const syncElapsed = Date.now() - syncStart;
+
+  // 6. Report results
+  console.log('\n=== Results ===\n');
+  console.log(`Status: ${sync.status}`);
+  console.log(`Time: ${(syncElapsed / 1000).toFixed(1)}s`);
+  console.log(`Blocks synced: ${stats.events.newBlock}`);
+  console.log(`Overall throughput: ${(stats.events.newBlock / (syncElapsed / 1000)).toFixed(1)} blocks/sec`);
+
+  console.log('\n--- Batch Sizing ---');
+  console.log(`Total batches: ${stats.events.batchComplete}`);
+  if (stats.batchSizes.length > 0) {
+    console.log(`Batch size range: ${Math.min(...stats.batchSizes)} → ${Math.max(...stats.batchSizes)}`);
+    const avgBatch = stats.batchSizes.reduce((a, b) => a + b, 0) / stats.batchSizes.length;
+    console.log(`Average batch size: ${avgBatch.toFixed(1)}`);
+    console.log(`Batch size progression: [${stats.batchSizes.join(', ')}]`);
+  }
+
+  console.log('\n--- Per-Block Timing ---');
+  if (stats.msPerBlock.length > 0) {
+    const avgMs = stats.msPerBlock.reduce((a, b) => a + b, 0) / stats.msPerBlock.length;
+    console.log(`Average ms/block: ${avgMs.toFixed(1)}`);
+    console.log(`Min ms/block: ${Math.min(...stats.msPerBlock)}`);
+    console.log(`Max ms/block: ${Math.max(...stats.msPerBlock)}`);
+    const avgBps = stats.blocksPerSec.reduce((a, b) => a + b, 0) / stats.blocksPerSec.length;
+    console.log(`Average blocks/sec (batch): ${avgBps.toFixed(1)}`);
+  }
+
+  console.log('\n--- Transactions ---');
+  console.log(`Miner TXs processed: ${stats.txCounts.minerTx}`);
+  console.log(`Protocol TXs processed: ${stats.txCounts.protocolTx}`);
+  console.log(`Regular TXs processed: ${stats.txCounts.regular}`);
+
+  console.log('\n--- Events ---');
+  console.log(`newBlock events: ${stats.events.newBlock}`);
+  console.log(`syncProgress events: ${stats.events.syncProgress}`);
+  console.log(`batchComplete events: ${stats.events.batchComplete}`);
+
+  if (stats.errors.length > 0) {
+    console.log('\n--- Errors ---');
+    for (const err of stats.errors) {
+      console.log(`  ${err}`);
+    }
+  }
+
+  // 7. Verify
+  console.log('\n--- Verification ---');
+  const finalHeight = await storage.getSyncHeight();
+  const expected = targetHeight;
+  const pass = sync.status === SYNC_STATUS.COMPLETE && finalHeight >= expected - 1;
+  console.log(`Final sync height: ${finalHeight}`);
+  console.log(`Expected: >= ${expected - 1}`);
+  console.log(`Status: ${pass ? 'PASS' : 'FAIL'}`);
+
+  await storage.close();
+
+  if (!pass) {
+    console.log('\nTest FAILED');
+    process.exit(1);
+  } else {
+    console.log('\nTest PASSED');
+    process.exit(0);
+  }
+}
+
+main().catch(e => {
+  console.error('Fatal:', e);
+  process.exit(1);
+});
diff --git a/test/wallet-sync.test.js b/test/wallet-sync.test.js
index 562ba14..7932b0a 100644
--- a/test/wallet-sync.test.js
+++ b/test/wallet-sync.test.js
@@ -97,6 +97,7 @@ class MockDaemon {
   async getBlock(opts) {
     const height = opts.height;
     this.callLog.push(`getBlock(${height})`);
+    const txHashes = this.blocks[height]?.txHashes || [];
     return {
       success: true,
       result: {
@@ -105,7 +106,11 @@ class MockDaemon {
           hash: `block_hash_${height}`,
           timestamp: 1700000000 + height * 120
         },
-        tx_hashes: this.blocks[height]?.txHashes || [],
+        json: JSON.stringify({
+          miner_tx: { version: 2, unlock_time: height + 60, vin: [{ gen: { height } }], vout: [], extra: [] },
+          tx_hashes: txHashes
+        }),
+        tx_hashes: txHashes,
         miner_tx_hash: `miner_tx_${height}`
       }
     };
@@ -153,8 +158,8 @@ test('SYNC_STATUS has correct values', () => {
   assertEqual(SYNC_STATUS.ERROR, 'error');
 });
 
-test('DEFAULT_BATCH_SIZE is 100', () => {
-  assertEqual(DEFAULT_BATCH_SIZE, 100);
+test('DEFAULT_BATCH_SIZE is 10', () => {
+  assertEqual(DEFAULT_BATCH_SIZE, 10);
 });
 
 test('SYNC_UNLOCK_BLOCKS is 10', () => {