diff --git a/lib/bcoin/txdb.js b/lib/bcoin/txdb.js
index 4cadaaa4..41c6c31d 100644
--- a/lib/bcoin/txdb.js
+++ b/lib/bcoin/txdb.js
@@ -14,11 +14,11 @@
  *   p/[hash] -> dummy (pending flag)
  *   m/[time]/[hash] -> dummy (tx by time)
  *   h/[height]/[hash] -> dummy (tx by height)
- *   T/[id]/[hash] -> dummy (tx by wallet id)
- *   P/[id]/[hash] -> dummy (pending tx by wallet id)
- *   M/[id]/[time]/[hash] -> dummy (tx by time + id)
- *   H/[id]/[height]/[hash] -> dummy (tx by height + id)
- *   C/[id]/[hash]/[index] -> dummy (coin by address)
+ *   T/[id]/[name]/[hash] -> dummy (tx by wallet id)
+ *   P/[id]/[name]/[hash] -> dummy (pending tx by wallet/account id)
+ *   M/[id]/[name]/[time]/[hash] -> dummy (tx by time + id/account)
+ *   H/[id]/[name]/[height]/[hash] -> dummy (tx by height + id/account)
+ *   C/[id]/[name]/[hash]/[index] -> dummy (coin by id/account)
  */
 
 var bcoin = require('./env');
@@ -40,7 +40,8 @@ var BufferWriter = require('./writer');
  * @param {Boolean?} options.indexAddress - Index addresses/IDs.
  * @param {Boolean?} options.indexExtra - Index timestamps, heights, etc.
  * @param {Boolean?} options.verify - Verify transactions as they
- * come in (note that this will not happen on the worker pool).
+ * come in (note that this will not happen on the worker
+ * pool -- only used for SPV).
  */
 
 function TXDB(db, options) {
@@ -52,7 +53,7 @@ function TXDB(db, options) {
   if (!options)
     options = {};
 
-  this.wdb = db;
+  this.walletdb = db;
   this.db = db.db;
   this.options = options;
   this.network = bcoin.network.get(options.network);
@@ -126,27 +127,8 @@ TXDB.prototype._testFilter = function _testFilter(addresses) {
  * @param {Function} callback - Returns [Error, {@link AddressMap}].
  */
 
-function uniq(obj) {
-  var uniq = {};
-  var out = [];
-  var i, key, value;
-
-  for (i = 0; i < obj.length; i++) {
-    value = obj[i];
-    key = value.id + '/' + value.account;
-
-    if (uniq[key])
-      continue;
-
-    uniq[key] = true;
-    out.push(value);
-  }
-
-  return out;
-}
-
 TXDB.prototype.getMap = function getMap(tx, callback) {
-  var input, output, addresses, table, map;
+  var i, input, output, address, addresses, table, map;
 
   input = tx.getInputHashes();
   output = tx.getOutputHashes();
@@ -155,7 +137,7 @@ TXDB.prototype.getMap = function getMap(tx, callback) {
   if (!this._testFilter(addresses))
     return callback();
 
-  function cb(err, table) {
+  this.mapAddresses(addresses, function(err, table) {
     if (err)
       return callback(err);
 
@@ -169,29 +151,29 @@ TXDB.prototype.getMap = function getMap(tx, callback) {
       all: []
     };
 
-    input.forEach(function(address) {
+    for (i = 0; i < input.length; i++) {
+      address = input[i];
       assert(map.table[address]);
       map.input = map.input.concat(map.table[address]);
-    });
+    }
 
-    output.forEach(function(address) {
+    for (i = 0; i < output.length; i++) {
+      address = output[i];
       assert(map.table[address]);
       map.output = map.output.concat(map.table[address]);
-    });
+    }
 
     map.input = uniq(map.input);
     map.output = uniq(map.output);
     map.all = uniq(map.input.concat(map.output));
 
     return callback(null, map);
-  }
-
-  return this.mapAddresses(addresses, cb);
+  });
 };
 
 /**
- * Map an address to a wallet ID.
- * @param {Base58Address|Base58Address[]} address
+ * Map address hashes to a wallet ID.
+ * @param {Hash[]} address - Address hashes.
  * @param {Function} callback - Returns [Error, {@link AddressTable}].
  */
 
@@ -201,7 +183,7 @@ TXDB.prototype.mapAddresses = function mapAddresses(address, callback) {
   var i, keys, values;
 
   return utils.forEachSerial(address, function(address, next) {
-    self.wdb.getAddress(address, function(err, paths) {
+    self.walletdb.getAddress(address, function(err, paths) {
       if (err)
         return next(err);
 
@@ -389,6 +371,7 @@ TXDB.prototype._add = function add(tx, map, callback, force) {
     // Consume unspent money or add orphans
     utils.forEachSerial(tx.inputs, function(input, next, i) {
       var key, address;
+      var prevout = input.prevout;
 
       if (tx.isCoinbase())
         return next();
@@ -399,11 +382,11 @@ TXDB.prototype._add = function add(tx, map, callback, force) {
       if (!address || !map.table[address].length)
         return next();
 
-      self.getCoin(input.prevout.hash, input.prevout.index, function(err, coin) {
+      self.getCoin(prevout.hash, prevout.index, function(err, coin) {
         if (err)
           return next(err);
 
-        key = input.prevout.hash + '/' + input.prevout.index;
+        key = prevout.hash + '/' + prevout.index;
 
         if (coin) {
           // Add TX to inputs and spend money
@@ -432,21 +415,21 @@ TXDB.prototype._add = function add(tx, map, callback, force) {
 
         input.coin = null;
 
-        self.isSpent(input.prevout.hash, input.prevout.index, function(err, spentBy) {
+        self.isSpent(prevout.hash, prevout.index, function(err, spentBy) {
           if (err)
             return next(err);
 
           // Are we double-spending?
           // Replace older txs with newer ones.
           if (spentBy) {
-            return self.getTX(input.prevout.hash, function(err, prev) {
+            return self.getTX(prevout.hash, function(err, prev) {
               if (err)
                 return next(err);
 
               if (!prev)
                 return callback(new Error('Could not find double-spent coin.'));
 
-              input.coin = bcoin.coin.fromTX(prev, input.prevout.index);
+              input.coin = bcoin.coin.fromTX(prev, prevout.index);
 
               // Skip invalid transactions
               if (self.options.verify) {
@@ -577,7 +560,7 @@ TXDB.prototype._add = function add(tx, map, callback, force) {
           if (err)
             return callback(err);
 
-          self.wdb.sync(tx, map, function(err) {
+          self.walletdb.sync(tx, map, function(err) {
             if (err)
               return callback(err);
 
@@ -768,7 +751,7 @@ TXDB.prototype._confirm = function _confirm(tx, map, callback, force) {
         if (err)
           return callback(err);
 
-        self.wdb.sync(tx, map, function(err) {
+        self.walletdb.sync(tx, map, function(err) {
           if (err)
             return callback(err);
 
@@ -1070,47 +1053,22 @@ TXDB.prototype._unconfirm = function unconfirm(tx, map, callback, force) {
 
 /**
  * Get hashes of all transactions in the database.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link Hash}[]].
  */
 
-TXDB.prototype.getHistoryHashes = function getHistoryHashes(address, callback) {
-  var self = this;
-  var txs = [];
-
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
-  }
-
-  callback = utils.ensure(callback);
-
-  if (Array.isArray(address)) {
-    return utils.forEachSerial(address, function(address, next) {
-      self.getHistoryHashes(address, function(err, tx) {
-        if (err)
-          return next(err);
-
-        txs = txs.concat(tx);
-
-        next();
-      });
-    }, function(err) {
-      if (err)
-        return callback(err);
-
-      txs = utils.uniq(txs);
-
-      return callback(null, txs);
-    });
+TXDB.prototype.getHistoryHashes = function getHistoryHashes(id, callback) {
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
   this.db.iterate({
-    gte: address ? 'T/' + address + '/' : 't',
-    lte: address ? 'T/' + address + '/~' : 't~',
+    gte: id ? 'T/' + id + '/' : 't',
+    lte: id ? 'T/' + id + '/~' : 't~',
     transform: function(key) {
       key = key.split('/');
-      if (address)
+      if (id)
         return key[3];
       return key[1];
     }
@@ -1119,48 +1077,22 @@ TXDB.prototype.getHistoryHashes = function getHistoryHashes(address, callback) {
 
 /**
  * Get hashes of all unconfirmed transactions in the database.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link Hash}[]].
  */
 
-TXDB.prototype.getUnconfirmedHashes = function getUnconfirmedHashes(address, callback) {
-  var self = this;
-  var txs = [];
-
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
-  }
-
-  callback = utils.ensure(callback);
-
-  if (Array.isArray(address)) {
-    return utils.forEachSerial(address, function(address, next) {
-      assert(address);
-      self.getUnconfirmedHashes(address, function(err, tx) {
-        if (err)
-          return next(err);
-
-        txs = txs.concat(tx);
-
-        next();
-      });
-    }, function(err) {
-      if (err)
-        return callback(err);
-
-      txs = utils.uniq(txs);
-
-      return callback(null, txs);
-    });
+TXDB.prototype.getUnconfirmedHashes = function getUnconfirmedHashes(id, callback) {
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
   this.db.iterate({
-    gte: address ? 'P/' + address + '/' : 'p',
-    lte: address ? 'P/' + address + '/~' : 'p~',
+    gte: id ? 'P/' + id + '/' : 'p',
+    lte: id ? 'P/' + id + '/~' : 'p~',
     transform: function(key) {
       key = key.split('/');
-      if (address)
+      if (id)
         return key[3];
       return key[1];
     }
@@ -1169,45 +1101,22 @@ TXDB.prototype.getUnconfirmedHashes = function getUnconfirmedHashes(address, cal
 
 /**
  * Get all coin hashes in the database.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link Hash}[]].
  */
 
-TXDB.prototype.getCoinHashes = function getCoinHashes(address, callback) {
-  var self = this;
-  var coins = [];
-
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
-  }
-
-  callback = utils.ensure(callback);
-
-  if (Array.isArray(address)) {
-    return utils.forEachSerial(address, function(address, next) {
-      self.getCoinHashes(address, function(err, coin) {
-        if (err)
-          return next(err);
-
-        coins = coins.concat(coin);
-
-        next();
-      });
-    }, function(err) {
-      if (err)
-        return callback(err);
-
-      return callback(null, coins);
-    });
+TXDB.prototype.getCoinHashes = function getCoinHashes(id, callback) {
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
   this.db.iterate({
-    gte: address ? 'C/' + address + '/' : 'c',
-    lte: address ? 'C/' + address + '/~' : 'c~',
+    gte: id ? 'C/' + id + '/' : 'c',
+    lte: id ? 'C/' + id + '/~' : 'c~',
     transform: function(key) {
       key = key.split('/');
-      if (address)
+      if (id)
         return [key[3], +key[4]];
       return [key[1], +key[2]];
     }
@@ -1216,7 +1125,7 @@ TXDB.prototype.getCoinHashes = function getCoinHashes(address, callback) {
 
 /**
  * Get TX hashes by height range.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Object} options
  * @param {Number} options.start - Start height.
  * @param {Number} options.end - End height.
@@ -1225,27 +1134,25 @@ TXDB.prototype.getCoinHashes = function getCoinHashes(address, callback) {
  * @param {Function} callback - Returns [Error, {@link Hash}[]].
  */
 
-TXDB.prototype.getHeightRangeHashes = function getHeightRangeHashes(address, options, callback) {
-  if (typeof address !== 'string') {
+TXDB.prototype.getHeightRangeHashes = function getHeightRangeHashes(id, options, callback) {
+  if (typeof id !== 'string') {
     callback = options;
-    options = address;
-    address = null;
+    options = id;
+    id = null;
   }
 
-  callback = utils.ensure(callback);
-
   this.db.iterate({
-    gte: address
-      ? 'H/' + address + '/' + pad32(options.start) + '/'
+    gte: id
+      ? 'H/' + id + '/' + pad32(options.start) + '/'
       : 'h/' + pad32(options.start) + '/',
-    lte: address
-      ? 'H/' + address + '/' + pad32(options.end) + '/~'
+    lte: id
+      ? 'H/' + id + '/' + pad32(options.end) + '/~'
       : 'h/' + pad32(options.end) + '/~',
     limit: options.limit,
     reverse: options.reverse,
     transform: function(key) {
       key = key.split('/');
-      if (address)
+      if (id)
         return key[4];
       return key[2];
     }
@@ -1264,7 +1171,7 @@ TXDB.prototype.getHeightHashes = function getHeightHashes(height, callback) {
 
 /**
  * Get TX hashes by timestamp range.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Object} options
  * @param {Number} options.start - Start height.
  * @param {Number} options.end - End height.
@@ -1273,26 +1180,24 @@ TXDB.prototype.getHeightHashes = function getHeightHashes(height, callback) {
  * @param {Function} callback - Returns [Error, {@link Hash}[]].
  */
 
-TXDB.prototype.getRangeHashes = function getRangeHashes(address, options, callback) {
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+TXDB.prototype.getRangeHashes = function getRangeHashes(id, options, callback) {
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  callback = utils.ensure(callback);
-
   this.db.iterate({
-    gte: address
-      ? 'M/' + address + '/' + pad32(options.start) + '/'
+    gte: id
+      ? 'M/' + id + '/' + pad32(options.start) + '/'
       : 'm/' + pad32(options.start) + '/',
-    lte: address
-      ? 'M/' + address + '/' + pad32(options.end) + '/~'
+    lte: id
+      ? 'M/' + id + '/' + pad32(options.end) + '/~'
       : 'm/' + pad32(options.end) + '/~',
     limit: options.limit,
     reverse: options.reverse,
     transform: function(key) {
       key = key.split('/');
-      if (address)
+      if (id)
         return key[4];
       return key[2];
     }
@@ -1301,7 +1206,7 @@ TXDB.prototype.getRangeHashes = function getRangeHashes(address, options, callba
 
 /**
  * Get transactions by timestamp range.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Object} options
  * @param {Number} options.start - Start height.
  * @param {Number} options.end - End height.
@@ -1310,16 +1215,16 @@ TXDB.prototype.getRangeHashes = function getRangeHashes(address, options, callba
  * @param {Function} callback - Returns [Error, {@link TX}[]].
  */
 
-TXDB.prototype.getRange = function getLast(address, options, callback) {
+TXDB.prototype.getRange = function getLast(id, options, callback) {
   var self = this;
   var txs = [];
 
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  return this.getRangeHashes(address, options, function(err, hashes) {
+  return this.getRangeHashes(id, options, function(err, hashes) {
     if (err)
       return callback(err);
 
@@ -1346,19 +1251,19 @@ TXDB.prototype.getRange = function getLast(address, options, callback) {
 
 /**
  * Get last N transactions.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Number} limit - Max number of transactions.
  * @param {Function} callback - Returns [Error, {@link TX}[]].
  */
 
-TXDB.prototype.getLast = function getLast(address, limit, callback) {
+TXDB.prototype.getLast = function getLast(id, limit, callback) {
   if (typeof limit === 'function') {
     callback = limit;
-    limit = address;
-    address = null;
+    limit = id;
+    id = null;
   }
 
-  return this.getRange(address, {
+  return this.getRange(id, {
     start: 0,
     end: 0xffffffff,
     reverse: true,
@@ -1368,20 +1273,20 @@ TXDB.prototype.getLast = function getLast(address, limit, callback) {
 
 /**
  * Get all transactions.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link TX}[]].
  */
 
-TXDB.prototype.getHistory = function getHistory(address, callback) {
+TXDB.prototype.getHistory = function getHistory(id, callback) {
   var self = this;
   var txs = [];
 
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  return this.getHistoryHashes(address, function(err, hashes) {
+  return this.getHistoryHashes(id, function(err, hashes) {
     if (err)
       return callback(err);
 
@@ -1408,32 +1313,34 @@ TXDB.prototype.getHistory = function getHistory(address, callback) {
 
 /**
  * Get last active timestamp and height.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, Number(ts), Number(height)].
  */
 
-TXDB.prototype.getLastTime = function getLastTime(address, callback) {
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+TXDB.prototype.getLastTime = function getLastTime(id, callback) {
+  var i, tx, lastTs, lastHeight;
+
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  return this.getHistory(address, function(err, txs) {
-    var lastTs, lastHeight;
-
+  return this.getHistory(id, function(err, txs) {
     if (err)
       return callback(err);
 
     lastTs = 0;
     lastHeight = -1;
 
-    txs.forEach(function(tx) {
+    for (i = 0; i < txs.length; i++) {
+      tx = txs[i];
+
       if (tx.ts > lastTs)
         lastTs = tx.ts;
 
       if (tx.height > lastHeight)
         lastHeight = tx.height;
-    });
+    }
 
     return callback(null, lastTs, lastHeight);
   });
@@ -1441,20 +1348,20 @@ TXDB.prototype.getLastTime = function getLastTime(address, callback) {
 
 /**
  * Get unconfirmed transactions.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link TX}[]].
  */
 
-TXDB.prototype.getUnconfirmed = function getUnconfirmed(address, callback) {
+TXDB.prototype.getUnconfirmed = function getUnconfirmed(id, callback) {
   var self = this;
   var txs = [];
 
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  return this.getUnconfirmedHashes(address, function(err, hashes) {
+  return this.getUnconfirmedHashes(id, function(err, hashes) {
     if (err)
       return callback(err);
 
@@ -1481,20 +1388,20 @@ TXDB.prototype.getUnconfirmed = function getUnconfirmed(address, callback) {
 
 /**
  * Get coins.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link Coin}[]].
  */
 
-TXDB.prototype.getCoins = function getCoins(address, callback) {
+TXDB.prototype.getCoins = function getCoins(id, callback) {
   var self = this;
   var coins = [];
 
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  return this.getCoinHashes(address, function(err, hashes) {
+  return this.getCoinHashes(id, function(err, hashes) {
     if (err)
       return callback(err);
 
@@ -1629,8 +1536,8 @@ TXDB.prototype.hasTX = function hasTX(hash, callback) {
  */
 
 TXDB.prototype.getCoin = function getCoin(hash, index, callback) {
-  this.db.fetch('c/' + hash + '/' + index, function(coin) {
-    coin = bcoin.coin.fromRaw(coin);
+  this.db.fetch('c/' + hash + '/' + index, function(data) {
+    var coin = bcoin.coin.fromRaw(data);
     coin.hash = hash;
     coin.index = index;
     return coin;
@@ -1649,39 +1556,21 @@ TXDB.prototype.hasCoin = function hasCoin(hash, index, callback) {
 
 /**
  * Calculate balance.
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Function} callback - Returns [Error, {@link Balance}].
  */
 
-TXDB.prototype.getBalance = function getBalance(address, callback) {
+TXDB.prototype.getBalance = function getBalance(id, callback) {
   var self = this;
   var confirmed = 0;
   var unconfirmed = 0;
 
-  if (typeof address === 'function') {
-    callback = address;
-    address = null;
+  if (typeof id === 'function') {
+    callback = id;
+    id = null;
   }
 
-  // return this.getCoins(address, function(err, coins) {
-  //   if (err)
-  //     return callback(err);
-  //
-  //   for (i = 0; i < coins.length; i++) {
-  //     if (coins[i].height === -1)
-  //       unconfirmed += coins[i].value;
-  //     else
-  //       confirmed += coins[i].value;
-  //   }
-  //
-  //   return callback(null, {
-  //     confirmed: confirmed,
-  //     unconfirmed: unconfirmed,
-  //     total: confirmed + unconfirmed
-  //   });
-  // });
-
-  return this.getCoinHashes(address, function(err, hashes) {
+  return this.getCoinHashes(id, function(err, hashes) {
     if (err)
       return callback(err);
 
@@ -1711,30 +1600,31 @@ TXDB.prototype.getBalance = function getBalance(address, callback) {
 };
 
 /**
- * @param {WalletID|WalletID[]} address - By address (can be null).
+ * @param {WalletID?} id
  * @param {Number} age - Age delta (delete transactions older than `now - age`).
  * @param {Function} callback
  */
 
-TXDB.prototype.zap = function zap(address, age, callback, force) {
+TXDB.prototype.zap = function zap(id, age, callback, force) {
   var self = this;
 
-  if (typeof address !== 'string') {
+  if (typeof age === 'function') {
     force = callback;
     callback = age;
-    age = address;
-    address = null;
+    age = id;
+    id = null;
   }
 
-  var unlock = this._lock(zap, [address, age, callback], force);
+  var unlock = this._lock(zap, [id, age, callback], force);
   if (!unlock)
     return;
 
   callback = utils.wrap(callback, unlock);
 
-  assert(utils.isNumber(age));
+  if (!utils.isNumber(age))
+    return callback(new Error('Age must be a number.'));
 
-  return this.getRange(address, {
+  return this.getRange(id, {
     start: 0,
     end: bcoin.now() - age
   }, function(err, txs) {
@@ -1748,12 +1638,35 @@ TXDB.prototype.zap = function zap(address, age, callback, force) {
       utils.forEachSerial(txs, function(tx, next) {
         if (tx.ts !== 0)
           return next();
-        self.lazyRemove(tx, next);
+        self.lazyRemove(tx, next, true);
       }, callback);
     });
   });
 };
 
+/*
+ * Helpers
+ */
+
+function uniq(obj) {
+  var uniq = {};
+  var out = [];
+  var i, key, value;
+
+  for (i = 0; i < obj.length; i++) {
+    value = obj[i];
+    key = value.id + '/' + value.account;
+
+    if (uniq[key])
+      continue;
+
+    uniq[key] = true;
+    out.push(value);
+  }
+
+  return out;
+}
+
 /*
  * Expose
  */
diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 98afee98..a19c2d97 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -2277,14 +2277,14 @@ utils.parallel = function parallel(stack, callback) {
 
   for (i = 0; i < stack.length; i++) {
     try {
-      if (0 && stack[i].length >= 2) {
-        stack[i](error, next);
-        error = null;
-      } else {
-        if (error)
-          continue;
-        stack[i](next);
-      }
+      // if (stack[i].length >= 2) {
+      //   stack[i](error, next);
+      //   error = null;
+      //   continue;
+      // }
+      if (error)
+        continue;
+      stack[i](next);
     } catch (e) {
       pending--;
       error = e;
@@ -2306,14 +2306,13 @@ utils.serial = function serial(stack, callback) {
     if (!cb)
       return callback(err);
 
-    if (0)
-    if (cb.length >= 2) {
-      try {
-        return cb(err, next);
-      } catch (e) {
-        return next(e);
-      }
-    }
+    // if (cb.length >= 2) {
+    //   try {
+    //     return cb(err, next);
+    //   } catch (e) {
+    //     return next(e);
+    //   }
+    // }
 
     if (err)
       return utils.nextTick(next.bind(null, err));
diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index 59fa4c81..dd67f312 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -76,6 +76,7 @@ function Wallet(options) {
   if (!this.id)
     this.id = this.getID();
 
+  // An in-memory database for testing.
   if (!this.db) {
     this.db = new bcoin.walletdb({
       network: this.network,
@@ -83,9 +84,6 @@ function Wallet(options) {
       db: 'memory'
     });
   }
-
-  // Non-alphanumeric IDs will break leveldb sorting.
-  assert(/^[a-zA-Z0-9]+$/.test(this.id), 'Wallet IDs must be alphanumeric.');
 }
 
 utils.inherits(Wallet, EventEmitter);
@@ -214,6 +212,7 @@ Wallet.prototype.addKey = function addKey(account, key, callback) {
     key = account;
     account = 0;
   }
+
   this.getAccount(account, function(err, account) {
     if (err)
       return callback(err);
@@ -238,6 +237,7 @@ Wallet.prototype.removeKey = function removeKey(account, key, callback) {
     key = account;
     account = 0;
   }
+
   this.getAccount(account, function(err, account) {
     if (err)
       return callback(err);
@@ -294,7 +294,7 @@ Wallet.prototype.createAccount = function createAccount(options, callback) {
 
   options = {
     network: this.network,
-    wid: this.id,
+    id: this.id,
     name: this.accountDepth === 0 ? 'default' : options.name,
     witness: options.witness,
     accountKey: key.hdPublicKey,
@@ -854,31 +854,31 @@ Wallet.prototype.zap = function zap(account, age, callback) {
 };
 
 /**
- * Scan for addresses.
- * @param {Function} getByAddress - Must be a callback which accepts
- * a callback and returns transactions by address.
- * @param {Function} callback - Returns [Error, Boolean, TX[]].
+ * Scan for active accounts and addresses. Used for importing a wallet.
+ * @param {Function} getByAddress - Must be a function which accepts
+ * a {@link Base58Address} as well as a callback and returns
+ * transactions by address.
+ * @param {Function} callback - Return [Error, Number] (total number
+ * of addresses allocated).
  */
 
 Wallet.prototype.scan = function scan(getByAddress, callback) {
   var self = this;
-  var result = false;
-  var txs = [];
+  var total = 0;
 
   (function next() {
     self.createAccount(self.options, function(err, account) {
       if (err)
         return callback(err);
 
-      account.scan(getByAddress, function(err, res, tx) {
+      account.scan(getByAddress, function(err, result) {
         if (err)
           return callback(err);
 
-        if (!res)
-          return callback(null, result, txs);
+        if (result === 0)
+          return callback(null, total);
 
-        result = true;
-        txs = txs.concat(tx);
+        total += result;
 
         next();
       });
@@ -978,6 +978,7 @@ Wallet.prototype.addTX = function addTX(tx, callback) {
 
 /**
  * Get all transactions in transaction history (accesses db).
+ * @param {(String|Number)?} account
  * @param {Function} callback - Returns [Error, {@link TX}[]].
  */
 
@@ -1444,8 +1445,8 @@ Wallet.fromJSON = function fromJSON(json) {
 
 Wallet.isWallet = function isWallet(obj) {
   return obj
-    && typeof obj.receiveDepth === 'number'
-    && obj.deriveAddress === 'function';
+    && typeof obj.accountDepth === 'number'
+    && obj.scriptInputs === 'function';
 };
 
 /**
@@ -1454,11 +1455,9 @@ Wallet.isWallet = function isWallet(obj) {
  * @constructor
  * @param {Object} options
  * @param {WalletDB} options.db
- * present, no coins will be available.
- * @param {(HDPrivateKey|HDPublicKey)?} options.master - Master HD key. If not
- * present, it will be generated.
+ * @param {HDPublicKey} options.accountKey
  * @param {Boolean?} options.witness - Whether to use witness programs.
- * @param {Number?} options.accountIndex - The BIP44 account index (default=0).
+ * @param {Number} options.accountIndex - The BIP44 account index.
  * @param {Number?} options.receiveDepth - The index of the _next_ receiving
  * address.
  * @param {Number?} options.changeDepth - The index of the _next_ change
@@ -1467,8 +1466,8 @@ Wallet.isWallet = function isWallet(obj) {
  * (default=pubkeyhash).
  * @param {Number?} options.m - `m` value for multisig.
  * @param {Number?} options.n - `n` value for multisig.
- * @param {String?} options.wid - Account ID (used for storage)
- * (default=account key "address").
+ * @param {String?} options.id - Wallet ID
+ * @param {String?} options.name - Account name
  */
 
 function Account(options) {
@@ -1481,19 +1480,20 @@ function Account(options) {
 
   assert(options, 'Options are required.');
   assert(options.db, 'Database is required.');
-  assert(options.wid, 'Wallet ID is required.');
+  assert(options.id, 'Wallet ID is required.');
   assert(options.accountKey, 'Account key is required.');
+  assert(utils.isNumber(options.accountIndex), 'Account index is required.');
 
   this.options = options;
   this.network = bcoin.network.get(options.network);
   this.db = options.db;
   this.lookahead = options.lookahead != null ? options.lookahead : 5;
 
-  this.wid = options.wid;
+  this.id = options.id;
   this.name = options.name;
   this.witness = options.witness || false;
   this.accountKey = options.accountKey;
-  this.accountIndex = options.accountIndex || 0;
+  this.accountIndex = options.accountIndex;
   this.receiveDepth = options.receiveDepth || 1;
   this.changeDepth = options.changeDepth || 1;
   this.type = options.type || 'pubkeyhash';
@@ -1949,7 +1949,7 @@ Account.prototype.save = function save(callback) {
  */
 
 Account.prototype.saveAddress = function saveAddress(address, callback) {
-  this.db.saveAddress(this.wid, address, callback);
+  this.db.saveAddress(this.id, address, callback);
 };
 
 /**
@@ -2032,92 +2032,62 @@ Account.prototype.setChangeDepth = function setChangeDepth(depth, callback) {
  * Scan for addresses.
  * @param {Function} getByAddress - Must be a callback which accepts
  * a callback and returns transactions by address.
- * @param {Function} callback - Returns [Boolean, TX[]].
+ * @param {Function} callback - Return [Error, Number] (total number
+ * of addresses allocated).
  */
 
 Account.prototype.scan = function scan(getByAddress, callback) {
   var self = this;
-  var result = false;
+  var total = 0;
 
-  return this._scan(getByAddress, function(err, depth, txs) {
-    if (err)
-      return callback(err);
+  if (!this.initialized)
+    return callback(new Error('Account is uninitialized.'));
 
-    self.setChangeDepth(depth.changeDepth + 1, function(err, res) {
+  function addTX(txs, calback) {
+    if (!Array.isArray(txs) || txs.length === 0)
+      return callback(null, false);
+
+    utils.forEachSerial(txs, function(tx, next) {
+      self.db.addTX(tx, next);
+    }, function(err) {
       if (err)
         return callback(err);
 
-      if (res)
-        result = true;
-
-      self.setReceiveDepth(depth.receiveDepth + 1, function(err, res) {
-        if (err)
-          return callback(err);
-
-        if (res)
-          result = true;
-
-        return callback(null, result, txs);
-      });
+      return callback(null, true);
     });
-  });
-};
-
-Account.prototype._scan = function _scan(getByAddress, callback) {
-  var self = this;
-  var depth = { changeDepth: 0, receiveDepth: 0 };
-  var all = [];
-
-  assert(this.initialized);
+  }
 
   (function chainCheck(change) {
-    var addressIndex = 0;
-    var total = 0;
     var gap = 0;
 
     (function next() {
-      var address = self.deriveAddress(change, addressIndex++);
-
-      getByAddress(address.getAddress(), function(err, txs) {
-        var result;
-
+      self.createAddress(change, function(err, address) {
         if (err)
           return callback(err);
 
-        if (txs) {
-          if (typeof txs === 'boolean')
-            result = txs;
-          else if (typeof txs === 'number')
-            result = txs > 0;
-          else if (Array.isArray(txs))
-            result = txs.length > 0;
-          else
-            result = false;
+        getByAddress(address.getAddress(), function(err, txs) {
+          if (err)
+            return callback(err);
 
-          if (Array.isArray(txs) && (txs[0] instanceof bcoin.tx))
-            all = all.concat(txs);
-        }
+          addTX(txs, function(err, result) {
+            if (err)
+              return callback(err);
 
-        if (result) {
-          total++;
-          gap = 0;
-          return next();
-        }
+            if (result) {
+              total++;
+              gap = 0;
+              return next();
+            }
 
-        if (++gap < 20)
-          return next();
+            if (++gap < 20)
+              return next();
 
-        assert(depth.receiveDepth === 0 || change === true);
+            if (!change)
+              return chainCheck(true);
 
-        if (change === false)
-          depth.receiveDepth = addressIndex - gap;
-        else
-          depth.changeDepth = addressIndex - gap;
-
-        if (change === false)
-          return chainCheck(true);
-
-        return callback(null, depth, all);
+            return callback(null, total);
+          });
+        });
       });
     })();
   })(false);
@@ -2130,9 +2100,9 @@ Account.prototype._scan = function _scan(getByAddress, callback) {
 
 Account.prototype.inspect = function inspect() {
   return {
-    wid: this.wid,
+    id: this.id,
     name: this.name,
-    network: this.network.type,
+    network: this.network,
     initialized: this.initialized,
     type: this.type,
     m: this.m,
@@ -2167,7 +2137,7 @@ Account.prototype.inspect = function inspect() {
 Account.prototype.toJSON = function toJSON() {
   return {
     network: this.network.type,
-    wid: this.wid,
+    id: this.id,
     name: this.name,
     initialized: this.initialized,
     type: this.type,
@@ -2198,7 +2168,7 @@ Account.prototype.toJSON = function toJSON() {
 Account.parseJSON = function parseJSON(json) {
   return {
     network: json.network,
-    wid: json.wid,
+    id: json.id,
     name: json.name,
     initialized: json.initialized,
     type: json.type,
@@ -2225,7 +2195,7 @@ Account.prototype.toRaw = function toRaw(writer) {
   var i;
 
   p.writeU32(this.network.magic);
-  p.writeVarString(this.wid, 'utf8');
+  p.writeVarString(this.id, 'utf8');
   p.writeVarString(this.name, 'utf8');
   p.writeU8(this.initialized ? 1 : 0);
   p.writeU8(this.type === 'pubkeyhash' ? 0 : 1);
@@ -2258,7 +2228,7 @@ Account.prototype.toRaw = function toRaw(writer) {
 Account.parseRaw = function parseRaw(data) {
   var p = new BufferReader(data);
   var network = bcoin.network.fromMagic(p.readU32());
-  var wid = p.readVarString('utf8');
+  var id = p.readVarString('utf8');
   var name = p.readVarString('utf8');
   var initialized = p.readU8() === 1;
   var type = p.readU8() === 0 ? 'pubkeyhash' : 'multisig';
@@ -2277,7 +2247,7 @@ Account.parseRaw = function parseRaw(data) {
 
   return {
     network: network.type,
-    wid: wid,
+    id: id,
     name: name,
     initialized: initialized,
     type: type,
diff --git a/lib/bcoin/walletdb.js b/lib/bcoin/walletdb.js
index 3ccf58a2..d313cf7c 100644
--- a/lib/bcoin/walletdb.js
+++ b/lib/bcoin/walletdb.js
@@ -10,6 +10,8 @@
  *  (inherits all from txdb)
  *  W/[address] -> id & path data
  *  w/[id] -> wallet
+ *  a/[id]/[index] -> account
+ *  i/[id]/[name] -> account index
  */
 
 var bcoin = require('./env');
@@ -346,140 +348,12 @@ WalletDB.prototype.get = function get(id, callback) {
  */
 
 WalletDB.prototype.save = function save(wallet, callback) {
+  if (!isAlpha(wallet.id))
+    return callback(new Error('Wallet IDs must be alphanumeric.'));
+
   this.db.put('w/' + wallet.id, wallet.toRaw(), callback);
 };
 
-/**
- * Get an account from the database.
- * @param {WalletID} id
- * @param {Function} callback - Returns [Error, {@link Wallet}].
- */
-
-WalletDB.prototype.getAccountIndex = function getAccountIndex(wid, name, callback) {
-  return this.db.get('i/' + wid + '/' + name, function(err, index) {
-    if (err && err.type !== 'NotFoundError')
-      return callback();
-
-    if (!index)
-      return callback(null, -1);
-
-    return callback(null, index.readUInt32LE(0, true));
-  });
-};
-
-WalletDB.prototype.getAccount = function getAccount(wid, id, callback) {
-  var self = this;
-  var aid = wid + '/' + id;
-  var account;
-
-  if (id == null)
-    return callback();
-
-  if (typeof id === 'string') {
-    return this.getAccountIndex(wid, id, function(err, index) {
-      if (err)
-        return callback(err);
-
-      if (index === -1)
-        return callback();
-
-      return self.getAccount(wid, index, callback);
-    });
-  }
-
-  this.db.get('a/' + aid, function(err, data) {
-    if (err && err.type !== 'NotFoundError')
-      return callback(err);
-
-    if (!data)
-      return callback();
-
-    try {
-      data = bcoin.account.parseRaw(data);
-      data.db = self;
-      account = new bcoin.account(data);
-    } catch (e) {
-      return callback(e);
-    }
-
-    account.open(function(err) {
-      if (err)
-        return callback(err);
-
-      return callback(null, account);
-    });
-  });
-};
-
-/**
- * Remove wallet from the database. Destroy wallet if passed in.
- * @param {WalletID} id
- * @param {Function} callback
- */
-
-WalletDB.prototype.remove = function remove(id, callback) {
-  this.db.del('w/' + id, function(err) {
-    if (err && err.type !== 'NotFoundError')
-      return callback(err);
-
-    return callback();
-  });
-};
-
-/**
- * Save a wallet to the database.
- * @param {Wallet} wallet
- * @param {Function} callback
- */
-
-WalletDB.prototype.saveAccount = function saveAccount(account, callback) {
-  var index = new Buffer(4);
-  var batch = this.db.batch();
-  index.writeUInt32LE(account.accountIndex, 0, true);
-  batch.put('a/' + account.wid + '/' + account.accountIndex, account.toRaw());
-  batch.put('i/' + account.wid + '/' + account.name, index);
-  batch.write(callback);
-};
-
-WalletDB.prototype.createAccount = function createAccount(options, callback) {
-  var self = this;
-  var account;
-
-  this.hasAccount(options.wid, options.accountIndex, function(err, exists) {
-    if (err)
-      return callback(err);
-
-    if (err)
-      return callback(err);
-
-    if (exists)
-      return callback(new Error('account already exists.'));
-
-    options = utils.merge({}, options);
-
-    if (self.network.witness)
-      options.witness = options.witness !== false;
-
-    options.network = self.network;
-    options.db = self;
-    account = new bcoin.account(options);
-
-    account.open(function(err) {
-      if (err)
-        return callback(err);
-
-      return callback(null, account);
-    });
-  });
-};
-
-WalletDB.prototype.hasAccount = function hasAccount(wid, account, callback) {
-  if (!wid || account == null)
-    return callback(null, false);
-
-  this.db.has('a/' + wid + '/' + account, callback);
-};
-
 /**
  * Create a new wallet, save to database, setup watcher.
  * @param {Object} options - See {@link Wallet}.
@@ -502,9 +376,6 @@ WalletDB.prototype.create = function create(options, callback) {
 
     options = utils.merge({}, options);
 
-    if (self.network.witness)
-      options.witness = options.witness !== false;
-
     options.network = self.network;
     options.db = self;
     wallet = new bcoin.wallet(options);
@@ -551,6 +422,160 @@ WalletDB.prototype.ensure = function ensure(options, callback) {
   });
 };
 
+/**
+ * Get an account from the database.
+ * @param {WalletID} id
+ * @param {String|Number} name - Account name/index.
+ * @param {Function} callback - Returns [Error, {@link Wallet}].
+ */
+
+WalletDB.prototype.getAccount = function getAccount(id, name, callback) {
+  var self = this;
+  var account;
+
+  return this.getAccountIndex(id, name, function(err, index) {
+    if (err)
+      return callback(err);
+
+    if (index === -1)
+      return callback();
+
+    self.db.get('a/' + id + '/' + index, function(err, data) {
+      if (err && err.type !== 'NotFoundError')
+        return callback(err);
+
+      if (!data)
+        return callback();
+
+      try {
+        data = bcoin.account.parseRaw(data);
+        data.db = self;
+        account = new bcoin.account(data);
+      } catch (e) {
+        return callback(e);
+      }
+
+      account.open(function(err) {
+        if (err)
+          return callback(err);
+
+        return callback(null, account);
+      });
+    });
+  });
+};
+
+/**
+ * Lookup the corresponding account name's index.
+ * @param {WalletID} id
+ * @param {String|Number} name - Account name/index.
+ * @param {Function} callback - Returns [Error, Number].
+ */
+
+WalletDB.prototype.getAccountIndex = function getAccountIndex(id, name, callback) {
+  if (name == null)
+    return callback(null, -1);
+
+  if (typeof name === 'number')
+    return callback(null, name);
+
+  return this.db.get('i/' + id + '/' + name, function(err, index) {
+    if (err && err.type !== 'NotFoundError')
+      return callback();
+
+    if (!index)
+      return callback(null, -1);
+
+    return callback(null, index.readUInt32LE(0, true));
+  });
+};
+
+
+/**
+ * Save an account to the database.
+ * @param {Account} account
+ * @param {Function} callback
+ */
+
+WalletDB.prototype.saveAccount = function saveAccount(account, callback) {
+  var index, batch;
+
+  if (!isAlpha(account.name))
+    return callback(new Error('Account names must be alphanumeric.'));
+
+  batch = this.db.batch();
+
+  index = new Buffer(4);
+  index.writeUInt32LE(account.accountIndex, 0, true);
+
+  batch.put('a/' + account.id + '/' + account.accountIndex, account.toRaw());
+  batch.put('i/' + account.id + '/' + account.name, index);
+
+  batch.write(callback);
+};
+
+/**
+ * Create an account.
+ * @param {Object} options - See {@link Account} options.
+ * @param {Function} callback - Returns [Error, {@link Account}].
+ */
+
+WalletDB.prototype.createAccount = function createAccount(options, callback) {
+  var self = this;
+  var account;
+
+  this.hasAccount(options.id, options.accountIndex, function(err, exists) {
+    if (err)
+      return callback(err);
+
+    if (err)
+      return callback(err);
+
+    if (exists)
+      return callback(new Error('Account already exists.'));
+
+    options = utils.merge({}, options);
+
+    if (self.network.witness)
+      options.witness = options.witness !== false;
+
+    options.network = self.network;
+    options.db = self;
+    account = new bcoin.account(options);
+
+    account.open(function(err) {
+      if (err)
+        return callback(err);
+
+      return callback(null, account);
+    });
+  });
+};
+
+/**
+ * Test for the existence of an account.
+ * @param {WalletID} id
+ * @param {String|Number} account
+ * @param {Function} callback - Returns [Error, Boolean].
+ */
+
+WalletDB.prototype.hasAccount = function hasAccount(id, account, callback) {
+  var self = this;
+
+  if (!id)
+    return callback(null, false);
+
+  this.getAccountIndex(id, account, function(err, index) {
+    if (err)
+      return callback(err);
+
+    if (index === -1)
+      return callback(null, false);
+
+    self.db.has('a/' + id + '/' + index, callback);
+  });
+};
+
 /**
  * Save an address to the path map.
  * The path map exists in the form of:
@@ -958,6 +983,10 @@ function serializePaths(out) {
   return p.render();
 }
 
+function isAlpha(key) {
+  return /^[a-zA-Z0-9]+$/.test(key);
+}
+
 /*
  * Expose
  */