diff --git a/lib/bcoin/blockdb.js b/lib/bcoin/blockdb.js
index 45cf4d2d..ee22765d 100644
--- a/lib/bcoin/blockdb.js
+++ b/lib/bcoin/blockdb.js
@@ -59,7 +59,7 @@ function BlockDB(options) {
     maxOpenFiles: 8192,
     // blockRestartInterval: 16,
     db: bcoin.isBrowser
-      ? require('memdown')
+      ? require('level-js')
       : require('level' + 'down')
   });
 }
diff --git a/lib/bcoin/pool.js b/lib/bcoin/pool.js
index 4f5375fb..c8543c57 100644
--- a/lib/bcoin/pool.js
+++ b/lib/bcoin/pool.js
@@ -1199,8 +1199,10 @@ Pool.prototype.addWallet = function addWallet(wallet, callback) {
 
   function search() {
     // Relay pending TXs
-    // NOTE: It is important to do it after search, because search could
-    // add TS to pending TXs, thus making them confirmed
+    // NOTE: It is important to do it after
+    // search, because search could add TS
+    // to pending TXs, thus making them
+    // confirmed.
     wallet.pending().forEach(function(tx) {
       self.sendTX(tx);
     });
diff --git a/lib/bcoin/walletdb.js b/lib/bcoin/walletdb.js
index c98f32c8..dbe90118 100644
--- a/lib/bcoin/walletdb.js
+++ b/lib/bcoin/walletdb.js
@@ -33,7 +33,10 @@ function WalletDB(options) {
   EventEmitter.call(this);
 
   this.options = options;
+
   this.file = options.file;
+  this.dir = options.dir;
+  this.type = options.type;
 
   if (!this.file)
     this.file = bcoin.dir + '/wallet-' + network.type + '.db';
@@ -42,7 +45,7 @@ function WalletDB(options) {
     this.dir = bcoin.dir + '/wallet-' + network.type;
 
   if (!this.type)
-    this.type = 'file';
+    this.type = 'leveldb';
 
   WalletDB.global = this;
 
@@ -83,7 +86,7 @@ WalletDB.prototype._init = function _init() {
     if (!WalletDB._db[this.file]) {
       WalletDB._db[this.file] = new levelup(this.file, {
         keyEncoding: 'ascii',
-        valueEncoding: 'json',
+        valueEncoding: 'utf8',
         createIfMissing: true,
         errorIfExists: false,
         compression: true,
@@ -93,7 +96,7 @@ WalletDB.prototype._init = function _init() {
         maxOpenFiles: 1024,
         // blockRestartInterval: 16,
         db: bcoin.isBrowser
-          ? require('memdown')
+          ? require('level-js')
           : require('level' + 'down')
       });
     }
@@ -129,6 +132,8 @@ WalletDB.prototype.saveDB = function saveFile(id, json, callback) {
 
   callback = utils.asyncify(callback);
 
+  json = JSON.stringify(json);
+
   this.db.put(key, json, callback);
 };
 
diff --git a/package.json b/package.json
index 17f6e363..cb93dc00 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
     "hash.js": "1.0.3",
     "inherits": "2.0.1",
     "leveldown": "1.4.4",
-    "memdown": "1.1.2",
+    "level-js": "2.2.3",
     "levelup": "1.3.1",
     "request": "2.67.0"
   },