diff --git a/.travis.yml b/.travis.yml
index bdd37d199..75f962332 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,6 @@
 language: python
 
 python:
-  - "2.7"
   - "3.6"
 
 install:
diff --git a/setup.py b/setup.py
index 57a7fe88e..c0c2f9d9b 100644
--- a/setup.py
+++ b/setup.py
@@ -18,7 +18,6 @@ setup(
         'Intended Audience :: Developers',
         'Intended Audience :: System Administrators',
         'License :: OSI Approved :: MIT License',
-        'Programming Language :: Python :: 2.7',
         'Programming Language :: Python :: 3',
         'Operating System :: OS Independent',
         'Topic :: Internet',
diff --git a/tests/unit/test_wallet.py b/tests/unit/test_wallet.py
index 5ca3bd904..12d591322 100644
--- a/tests/unit/test_wallet.py
+++ b/tests/unit/test_wallet.py
@@ -11,7 +11,7 @@ class TestWalletCreation(unittest.TestCase):
 
     def setUp(self):
         self.manager = WalletManager()
-        config = {'wallet_path': '/tmp/wallet'}
+        config = {'data_path': '/tmp/wallet'}
         self.btc_ledger = self.manager.get_or_create_ledger(BTCLedger.get_id(), config)
         self.bch_ledger = self.manager.get_or_create_ledger(BCHLedger.get_id(), config)
 
@@ -28,6 +28,7 @@ class TestWalletCreation(unittest.TestCase):
 
     def test_load_and_save_wallet(self):
         wallet_dict = {
+            'version': 1,
             'name': 'Main Wallet',
             'accounts': [
                 {
@@ -61,11 +62,11 @@ class TestWalletCreation(unittest.TestCase):
 
     def test_read_write(self):
         manager = WalletManager()
-        config = {'wallet_path': '/tmp/wallet'}
+        config = {'data_path': '/tmp/wallet'}
         ledger = manager.get_or_create_ledger(BTCLedger.get_id(), config)
 
         with tempfile.NamedTemporaryFile(suffix='.json') as wallet_file:
-            wallet_file.write(b'{}')
+            wallet_file.write(b'{"version": 1}')
             wallet_file.seek(0)
 
             # create and write wallet to a file
diff --git a/torba/baseaccount.py b/torba/baseaccount.py
index d2a5b0c82..524133495 100644
--- a/torba/baseaccount.py
+++ b/torba/baseaccount.py
@@ -64,7 +64,7 @@ class KeyChain:
         defer.returnValue(addresses[0])
 
 
-class BaseAccount:
+class BaseAccount(object):
 
     mnemonic_class = Mnemonic
     private_key_class = PrivateKey
diff --git a/torba/baseledger.py b/torba/baseledger.py
index 5e0396bd3..247be00c9 100644
--- a/torba/baseledger.py
+++ b/torba/baseledger.py
@@ -109,7 +109,7 @@ class BaseLedger(six.with_metaclass(LedgerRegistry)):
 
     @property
     def path(self):
-        return os.path.join(self.config['wallet_path'], self.get_id())
+        return os.path.join(self.config['data_path'], self.get_id())
 
     def get_input_output_fee(self, io):
         """ Fee based on size of the input / output. """
diff --git a/torba/wallet.py b/torba/wallet.py
index 0ff419089..e41208329 100644
--- a/torba/wallet.py
+++ b/torba/wallet.py
@@ -44,6 +44,7 @@ class Wallet:
 
     def to_dict(self):
         return {
+            'version': WalletStorage.LATEST_VERSION,
             'name': self.name,
             'accounts': [a.to_dict() for a in self.accounts]
         }
diff --git a/tox.ini b/tox.ini
index d006596dc..746107260 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,16 +1,16 @@
 [tox]
-#envlist = py{27,36}-unit,py36-integration-{torba.coin.bitcoincash,torba.coin.bitcoinsegwit}
-envlist = py{27,36}-unit,py36-integration-torba.coin.bitcoinsegwit
+#envlist = unit,integration-{torba.coin.bitcoincash,torba.coin.bitcoinsegwit}
+envlist = unit,integration-torba.coin.bitcoinsegwit
 
 [testenv]
 deps =
   coverage
-  py36-integration: ../orchstr8
-  py36-integration: ../electrumx
+  integration: ../orchstr8
+  integration: ../electrumx
 extras = test
 changedir = {toxinidir}/tests
-setenv = py36-integration: LEDGER={envname}
+setenv = integration: LEDGER={envname}
 commands =
-  py{27,36}-unit: coverage run -p --source={envsitepackagesdir}/torba -m twisted.trial unit
-  py36-integration: orchstr8 download
-  py36-integration: coverage run -p --source={envsitepackagesdir}/torba -m twisted.trial --reactor=asyncio integration
+  unit: coverage run -p --source={envsitepackagesdir}/torba -m twisted.trial unit
+  integration: orchstr8 download
+  integration: coverage run -p --source={envsitepackagesdir}/torba -m twisted.trial --reactor=asyncio integration