diff --git a/lib/wallet/records.js b/lib/wallet/records.js
index 460ae1c7..4279d5b3 100644
--- a/lib/wallet/records.js
+++ b/lib/wallet/records.js
@@ -237,8 +237,7 @@ function BlockMapRecord(height) {
     return new BlockMapRecord(height);
 
   this.height = height != null ? height : -1;
-  this.txs = [];
-  this.index = new Map();
+  this.txs = new Map();
 }
 
 /**
@@ -255,8 +254,7 @@ BlockMapRecord.prototype.fromRaw = function fromRaw(data) {
   for (let i = 0; i < count; i++) {
     let hash = br.readHash('hex');
     let tx = TXMapRecord.fromReader(hash, br);
-    this.txs.push(tx);
-    this.index.set(tx.hash, tx);
+    this.txs.set(tx.hash, tx);
   }
 
   return this;
@@ -283,7 +281,7 @@ BlockMapRecord.prototype.getSize = function getSize() {
 
   size += 4;
 
-  for (let tx of this.txs) {
+  for (let tx of this.txs.values()) {
     size += 32;
     size += tx.getSize();
   }
@@ -301,10 +299,10 @@ BlockMapRecord.prototype.toRaw = function toRaw() {
   let size = this.getSize();
   let bw = new StaticWriter(size);
 
-  bw.writeU32(this.txs.length);
+  bw.writeU32(this.txs.size);
 
-  for (let tx of this.txs) {
-    bw.writeHash(tx.hash);
+  for (let [hash, tx] of this.txs) {
+    bw.writeHash(hash);
     tx.toWriter(bw);
   }
 
@@ -319,14 +317,11 @@ BlockMapRecord.prototype.toRaw = function toRaw() {
  */
 
 BlockMapRecord.prototype.add = function add(hash, wid) {
-  let tx = this.index.get(hash);
+  let tx = this.txs.get(hash);
 
   if (!tx) {
     tx = new TXMapRecord(hash);
-    tx.wids.push(wid);
-    this.txs.push(tx);
-    this.index.set(tx.hash, tx);
-    return true;
+    this.txs.set(tx.hash, tx);
   }
 
   return tx.add(wid);
@@ -340,7 +335,7 @@ BlockMapRecord.prototype.add = function add(hash, wid) {
  */
 
 BlockMapRecord.prototype.remove = function remove(hash, wid) {
-  let tx = this.index.get(hash);
+  let tx = this.txs.get(hash);
 
   if (!tx)
     return false;
@@ -348,15 +343,26 @@ BlockMapRecord.prototype.remove = function remove(hash, wid) {
   if (!tx.remove(wid))
     return false;
 
-  if (tx.wids.length === 0) {
-    let result = util.binaryRemove(this.txs, tx, cmpid);
-    assert(result);
-    this.index.delete(tx.hash);
-  }
+  if (tx.wids.size === 0)
+    this.txs.delete(tx.hash);
 
   return true;
 };
 
+/**
+ * Convert tx map to an array.
+ * @returns {Array}
+ */
+
+BlockMapRecord.prototype.toArray = function toArray() {
+  let txs = [];
+
+  for (let tx of this.txs.values())
+    txs.push(tx);
+
+  return txs;
+};
+
 /**
  * TX Hash
  * @constructor
@@ -364,18 +370,19 @@ BlockMapRecord.prototype.remove = function remove(hash, wid) {
 
 function TXMapRecord(hash, wids) {
   this.hash = hash || encoding.NULL_HASH;
-  this.wids = wids || [];
-  this.id = TXMapRecord.id++;
+  this.wids = wids || new Set();
 }
 
-TXMapRecord.id = 0;
-
 TXMapRecord.prototype.add = function add(wid) {
-  return util.binaryInsert(this.wids, wid, cmp, true) !== -1;
+  if (this.wids.has(wid))
+    return false;
+
+  this.wids.add(wid);
+  return true;
 };
 
 TXMapRecord.prototype.remove = function remove(wid) {
-  return util.binaryRemove(this.wids, wid, cmp);
+  return this.wids.delete(wid);
 };
 
 TXMapRecord.prototype.toWriter = function toWriter(bw) {
@@ -416,15 +423,19 @@ TXMapRecord.fromRaw = function fromRaw(hash, data) {
 function OutpointMapRecord(hash, index, wids) {
   this.hash = hash || encoding.NULL_HASH;
   this.index = index != null ? index : -1;
-  this.wids = wids || [];
+  this.wids = wids || new Set();
 }
 
 OutpointMapRecord.prototype.add = function add(wid) {
-  return util.binaryInsert(this.wids, wid, cmp, true) !== -1;
+  if (this.wids.has(wid))
+    return false;
+
+  this.wids.add(wid);
+  return true;
 };
 
 OutpointMapRecord.prototype.remove = function remove(wid) {
-  return util.binaryRemove(this.wids, wid, cmp);
+  return this.wids.delete(wid);
 };
 
 OutpointMapRecord.prototype.toWriter = function toWriter(bw) {
@@ -464,15 +475,19 @@ OutpointMapRecord.fromRaw = function fromRaw(hash, index, data) {
 
 function PathMapRecord(hash, wids) {
   this.hash = hash || encoding.NULL_HASH;
-  this.wids = wids || [];
+  this.wids = wids || new Set();
 }
 
 PathMapRecord.prototype.add = function add(wid) {
-  return util.binaryInsert(this.wids, wid, cmp, true) !== -1;
+  if (this.wids.has(wid))
+    return false;
+
+  this.wids.add(wid);
+  return true;
 };
 
 PathMapRecord.prototype.remove = function remove(wid) {
-  return util.binaryRemove(this.wids, wid, cmp);
+  return this.wids.delete(wid);
 };
 
 PathMapRecord.prototype.toWriter = function toWriter(bw) {
@@ -701,30 +716,22 @@ TXRecord.fromRaw = function fromRaw(data) {
  * Helpers
  */
 
-function cmp(a, b) {
-  return a - b;
-}
-
-function cmpid(a, b) {
-  return a.id - b.id;
-}
-
 function parseWallets(br) {
   let count = br.readU32();
-  let wids = [];
+  let wids = new Set();
 
   for (let i = 0; i < count; i++)
-    wids.push(br.readU32());
+    wids.add(br.readU32());
 
   return wids;
 }
 
 function sizeWallets(wids) {
-  return 4 + wids.length * 4;
+  return 4 + wids.size * 4;
 }
 
 function serializeWallets(bw, wids) {
-  bw.writeU32(wids.length);
+  bw.writeU32(wids.size);
 
   for (let wid of wids)
     bw.writeU32(wid);
diff --git a/lib/wallet/txdb.js b/lib/wallet/txdb.js
index aef5f0bc..9ccd2f58 100644
--- a/lib/wallet/txdb.js
+++ b/lib/wallet/txdb.js
@@ -520,7 +520,7 @@ TXDB.prototype.removeOutpointMap = async function removeOutpointMap(hash, i) {
   if (!map.remove(this.wallet.wid))
     return;
 
-  if (map.wids.length === 0) {
+  if (map.wids.size === 0) {
     this.walletdb.unwriteOutpointMap(this.wallet, hash, i);
     return;
   }
@@ -563,7 +563,7 @@ TXDB.prototype.removeBlockMap = async function removeBlockMap(hash, height) {
   if (!block.remove(hash, this.wallet.wid))
     return;
 
-  if (block.txs.length === 0) {
+  if (block.txs.size === 0) {
     this.walletdb.unwriteBlockMap(this.wallet, height);
     return;
   }
@@ -795,6 +795,7 @@ TXDB.prototype.insert = async function insert(wtx, block) {
   let hash = wtx.hash;
   let height = block ? block.height : -1;
   let details = new Details(this, wtx, block);
+  let accounts = new Set();
   let own = false;
   let updated = false;
 
@@ -838,6 +839,7 @@ TXDB.prototype.insert = async function insert(wtx, block) {
       // Build the tx details object
       // as we go, for speed.
       details.setInput(i, path, coin);
+      accounts.add(path.account);
 
       // Write an undo coin for the credit
       // and add it to the stxo set.
@@ -886,6 +888,7 @@ TXDB.prototype.insert = async function insert(wtx, block) {
       continue;
 
     details.setOutput(i, path);
+    accounts.add(path.account);
 
     // Attempt to resolve an input we
     // did not know was ours at the time.
@@ -928,7 +931,7 @@ TXDB.prototype.insert = async function insert(wtx, block) {
   // Do some secondary indexing for account-based
   // queries. This saves us a lot of time for
   // queries later.
-  for (let account of details.accounts) {
+  for (let account of accounts) {
     this.put(layout.T(account, hash), null);
     this.put(layout.M(account, wtx.ps, hash), null);
 
@@ -1013,6 +1016,7 @@ TXDB.prototype._confirm = async function confirm(wtx, block) {
   let hash = wtx.hash;
   let height = block.height;
   let details = new Details(this, wtx, block);
+  let accounts = new Set();
 
   wtx.setBlock(block);
 
@@ -1055,6 +1059,7 @@ TXDB.prototype._confirm = async function confirm(wtx, block) {
       assert(path);
 
       details.setInput(i, path, coin);
+      accounts.add(path.account);
 
       // We can now safely remove the credit
       // entirely, now that we know it's also
@@ -1075,6 +1080,7 @@ TXDB.prototype._confirm = async function confirm(wtx, block) {
       continue;
 
     details.setOutput(i, path);
+    accounts.add(path.account);
 
     credit = await this.getCredit(hash, i);
     assert(credit);
@@ -1107,7 +1113,7 @@ TXDB.prototype._confirm = async function confirm(wtx, block) {
   this.put(layout.h(height, hash), null);
 
   // Secondary indexing also needs to change.
-  for (let account of details.accounts) {
+  for (let account of accounts) {
     this.del(layout.P(account, hash));
     this.put(layout.H(account, height, hash), null);
   }
@@ -1157,6 +1163,7 @@ TXDB.prototype.erase = async function erase(wtx, block) {
   let hash = wtx.hash;
   let height = block ? block.height : -1;
   let details = new Details(this, wtx, block);
+  let accounts = new Set();
 
   if (!tx.isCoinbase()) {
     // We need to undo every part of the
@@ -1181,6 +1188,7 @@ TXDB.prototype.erase = async function erase(wtx, block) {
       assert(path);
 
       details.setInput(i, path, coin);
+      accounts.add(path.account);
 
       // Recalculate the balance, remove
       // from stxo set, remove the undo
@@ -1207,6 +1215,7 @@ TXDB.prototype.erase = async function erase(wtx, block) {
       continue;
 
     details.setOutput(i, path);
+    accounts.add(path.account);
 
     credit = Credit.fromTX(tx, i, height);
 
@@ -1233,7 +1242,7 @@ TXDB.prototype.erase = async function erase(wtx, block) {
     this.del(layout.h(height, hash));
 
   // Remove all secondary indexing.
-  for (let account of details.accounts) {
+  for (let account of accounts) {
     this.del(layout.T(account, hash));
     this.del(layout.M(account, wtx.ps, hash));
 
@@ -1354,6 +1363,7 @@ TXDB.prototype.disconnect = async function disconnect(wtx, block) {
   let hash = wtx.hash;
   let height = block.height;
   let details = new Details(this, wtx, block);
+  let accounts = new Set();
 
   assert(block);
 
@@ -1380,6 +1390,7 @@ TXDB.prototype.disconnect = async function disconnect(wtx, block) {
       assert(path);
 
       details.setInput(i, path, coin);
+      accounts.add(path.account);
 
       this.pending.confirmed += coin.value;
 
@@ -1412,6 +1423,7 @@ TXDB.prototype.disconnect = async function disconnect(wtx, block) {
       await this.updateSpentCoin(tx, i, height);
 
     details.setOutput(i, path);
+    accounts.add(path.account);
 
     // Update coin height and confirmed
     // balance. Save once again.
@@ -1434,7 +1446,7 @@ TXDB.prototype.disconnect = async function disconnect(wtx, block) {
   this.del(layout.h(height, hash));
 
   // Secondary indexing also needs to change.
-  for (let account of details.accounts) {
+  for (let account of accounts) {
     this.put(layout.P(account, hash), null);
     this.del(layout.H(account, height, hash));
   }
@@ -2856,7 +2868,6 @@ function Details(txdb, wtx, block) {
 
   this.inputs = [];
   this.outputs = [];
-  this.accounts = [];
 
   this.init();
 }
@@ -2896,10 +2907,8 @@ Details.prototype.setInput = function setInput(i, path, coin) {
     member.address = coin.getAddress();
   }
 
-  if (path) {
+  if (path)
     member.path = path;
-    util.binaryInsert(this.accounts, path.account, cmp, true);
-  }
 };
 
 /**
@@ -2911,10 +2920,8 @@ Details.prototype.setInput = function setInput(i, path, coin) {
 Details.prototype.setOutput = function setOutput(i, path) {
   let member = this.outputs[i];
 
-  if (path) {
+  if (path)
     member.path = path;
-    util.binaryInsert(this.accounts, path.account, cmp, true);
-  }
 };
 
 /**
@@ -3220,14 +3227,6 @@ BlockRecord.fromMeta = function fromMeta(block) {
   return new BlockRecord().fromMeta(block);
 };
 
-/*
- * Helpers
- */
-
-function cmp(a, b) {
-  return a - b;
-}
-
 /*
  * Expose
  */
diff --git a/lib/wallet/walletdb.js b/lib/wallet/walletdb.js
index bd044012..aee1e5dd 100644
--- a/lib/wallet/walletdb.js
+++ b/lib/wallet/walletdb.js
@@ -1880,11 +1880,12 @@ WalletDB.prototype.revert = async function revert(target) {
     try {
       let height = layout.bb(item.key);
       let block = BlockMapRecord.fromRaw(height, item.value);
+      let txs = block.toArray();
 
-      total += block.txs.length;
+      total += txs.length;
 
-      for (let i = block.txs.length - 1; i >= 0; i--) {
-        let tx = block.txs[i];
+      for (let i = txs.length - 1; i >= 0; i--) {
+        let tx = txs[i];
         await this._unconfirm(tx);
       }
     } catch (e) {
@@ -1988,7 +1989,7 @@ WalletDB.prototype.removeBlock = async function removeBlock(entry) {
 
 WalletDB.prototype._removeBlock = async function removeBlock(entry) {
   let tip = BlockMeta.fromEntry(entry);
-  let prev, block;
+  let prev, block, txs;
 
   if (tip.height > this.state.height) {
     this.logger.warning(
@@ -2013,8 +2014,10 @@ WalletDB.prototype._removeBlock = async function removeBlock(entry) {
     return 0;
   }
 
-  for (let i = block.txs.length - 1; i >= 0; i--) {
-    let tx = block.txs[i];
+  txs = block.toArray();
+
+  for (let i = txs.length - 1; i >= 0; i--) {
+    let tx = txs[i];
     await this._unconfirm(tx);
   }
 
@@ -2022,9 +2025,9 @@ WalletDB.prototype._removeBlock = async function removeBlock(entry) {
   await this.syncState(prev);
 
   this.logger.warning('Disconnected wallet block %s (tx=%d).',
-    util.revHex(tip.hash), block.txs.length);
+    util.revHex(tip.hash), block.txs.size);
 
-  return block.txs.length;
+  return block.txs.size;
 };
 
 /**
@@ -2086,7 +2089,7 @@ WalletDB.prototype._insert = async function insert(tx, block) {
 
   this.logger.info(
     'Incoming transaction for %d wallets in WalletDB (%s).',
-    wids.length, tx.txid());
+    wids.size, tx.txid());
 
   // If this is our first transaction
   // in a block, set the start block here.