diff --git a/lib/storage.js b/lib/storage.js
index c9e6ac4..c1f1a2c 100644
--- a/lib/storage.js
+++ b/lib/storage.js
@@ -17,6 +17,7 @@ var collections = {
   TXS: 'txs',
   ADDRESSES: 'addresses',
   NOTIFICATIONS: 'notifications',
+  COPAYERS_LOOKUP: 'copayers_lookup',
 };
 
 var Storage = function(opts) {
@@ -74,44 +75,38 @@ Storage.prototype.storeWallet = function(wallet, cb) {
 };
 
 Storage.prototype.storeWalletAndUpdateCopayersLookup = function(wallet, cb) {
-  return this.storeWallet(wallet, cb);
-};
+  var self = this;
 
-Storage.prototype.fetchCopayerLookup2 = function(copayerId, cb) {
-  this.db.collection(collections.WALLETS).findOne({
-    'copayers.id': copayerId
-  }, function(err, result) {
-    if (err) return cb(err);
-    if (!result) return cb();
-    var copayer = _.find(result.copayers, {
-      id: copayerId
-    });
-    return cb(null, {
-      walletId: result.id,
+  var copayerLookups = _.map(wallet.copayers, function(copayer) {
+    return {
+      copayerId: copayer.id,
+      walletId: wallet.id,
       requestPubKey: copayer.requestPubKey,
+    };
+  });
+
+  this.db.collection(collections.COPAYERS_LOOKUP).remove({
+    walletId: wallet.id
+  }, {
+    w: 1
+  }, function(err) {
+    if (err) return cb(err);
+    self.db.collection(collections.COPAYERS_LOOKUP).insert(copayerLookups, {
+      w: 1
+    }, function(err) {
+      if (err) return cb(err);
+      return self.storeWallet(wallet, cb);
     });
   });
 };
 
 Storage.prototype.fetchCopayerLookup = function(copayerId, cb) {
-  this.db.collection(collections.WALLETS).find({}).toArray(function(err, result) {
+  this.db.collection(collections.COPAYERS_LOOKUP).findOne({
+    copayerId: copayerId
+  }, function(err, result) {
     if (err) return cb(err);
-
-    result = _.find(result, function(w) {
-      return _.any(w.copayers, {
-        id: copayerId
-      });
-    });
-
-
     if (!result) return cb();
-    var copayer = _.find(result.copayers, {
-      id: copayerId
-    });
-    return cb(null, {
-      walletId: result.id,
-      requestPubKey: copayer.requestPubKey,
-    });
+    return cb(null, result);
   });
 };
 
@@ -278,18 +273,11 @@ Storage.prototype.removeWallet = function(walletId, cb) {
       }, next);
     },
     function(next) {
-      self.db.collection(collections.ADDRESSES).remove({
-        walletId: walletId
-      }, next);
-    },
-    function(next) {
-      self.db.collection(collections.TXS).remove({
-        walletId: walletId
-      }, next);
-    },
-    function(next) {
-      self.db.collection(collections.NOTIFICATIONS).remove({
-        walletId: walletId
+      var otherCollections = _.without(_.values(collections), collections.WALLETS);
+      async.each(otherCollections, function(col, next) {
+        self.db.collection(col).remove({
+          walletId: walletId
+        }, next);
       }, next);
     },
   ], cb);
diff --git a/test/integration/server.js b/test/integration/server.js
index 87cae74..165fc31 100644
--- a/test/integration/server.js
+++ b/test/integration/server.js
@@ -11,7 +11,9 @@ var log = require('npmlog');
 log.debug = log.verbose;
 
 var fs = require('fs');
-var tingodb = require('tingodb')();
+var tingodb = require('tingodb')({
+  memStore: true
+});
 
 var Utils = require('../../lib/utils');
 var WalletUtils = require('bitcore-wallet-utils');
@@ -212,15 +214,8 @@ helpers.createAddresses = function(server, wallet, main, change, cb) {
 var db, storage, blockchainExplorer;
 
 function openDb(cb) {
-  var tingodb = require('tingodb')();
-  var dbDir = './db/test/';
-  fs.mkdir(dbDir, function(err) {
-    if (err && err.code != 'EEXIST') {
-      throw new Error('Could not create test db directory at ./db/test/');
-    }
-    db = new tingodb.Db(dbDir, {});
-    return cb();
-  });
+  db = new tingodb.Db('./db/test', {});
+  return cb();
 };
 
 function resetDb(cb) {
diff --git a/test/storage.js b/test/storage.js
index f3240b7..5f5ff87 100644
--- a/test/storage.js
+++ b/test/storage.js
@@ -5,34 +5,41 @@ var async = require('async');
 var chai = require('chai');
 var sinon = require('sinon');
 var should = chai.should();
-var mongodb = require('mongodb');
+var tingodb = require('tingodb')({
+  memStore: true
+});
 
 var Storage = require('../lib/storage');
 var Model = require('../lib/model');
 
+var db, storage;
 
-function initDb(cb) {
-  var url = 'mongodb://localhost:27017';
-  mongodb.MongoClient.connect(url, function(err, db) {
-    should.not.exist(err);
-    db.dropDatabase(function(err) {
-      return cb(null, db);
-    });
+function openDb(cb) {
+  db = new tingodb.Db('./db/test', {});
+  return cb();
+};
+
+function resetDb(cb) {
+  if (!db) return cb();
+  db.dropDatabase(function(err) {
+    return cb();
   });
 };
 
 
 describe('Storage', function() {
-  var storage;
-  beforeEach(function(done) {
-    initDb(function(err, db) {
-      should.not.exist(err);
+  before(function(done) {
+    openDb(function() {
       storage = new Storage({
         db: db
       });
       done();
     });
   });
+  beforeEach(function(done) {
+    resetDb(done);
+  });
+
   describe('Store & fetch wallet', function() {
     it('should correctly store and fetch wallet', function(done) {
       var wallet = Model.Wallet.create({