diff --git a/lib/tests/test_transaction.py b/lib/tests/test_transaction.py
new file mode 100644
index 000000000..f892eef10
--- /dev/null
+++ b/lib/tests/test_transaction.py
@@ -0,0 +1,114 @@
+import unittest
+from lib import transaction
+
+import pprint
+
+unsigned_blob = '01000000012a5c9a94fcde98f5581cd00162c60a13936ceb75389ea65bf38633b424eb4031000000005701ff4c53ff0488b21e03ef2afea18000000089689bff23e1e7fb2f161daa37270a97a3d8c2e537584b2d304ecb47b86d21fc021b010d3bd425f8cf2e04824bfdf1f1f5ff1d51fadd9a41f9e3fb8dd3403b1bfe00000000ffffffff0140420f00000000001976a914230ac37834073a42146f11ef8414ae929feaafc388ac00000000'
+signed_blob = '01000000012a5c9a94fcde98f5581cd00162c60a13936ceb75389ea65bf38633b424eb4031000000006c493046022100a82bbc57a0136751e5433f41cf000b3f1a99c6744775e76ec764fb78c54ee100022100f9e80b7de89de861dc6fb0c1429d5da72c2b6b2ee2406bc9bfb1beedd729d985012102e61d176da16edd1d258a200ad9759ef63adf8e14cd97f53227bae35cdb84d2f6ffffffff0140420f00000000001976a914230ac37834073a42146f11ef8414ae929feaafc388ac00000000'
+
+
+class TestTransaction(unittest.TestCase):
+
+    def test_tx_unsigned(self):
+        expected = {
+            'inputs': [{
+                'address': '1446oU3z268EeFgfcwJv6X2VBXHfoYxfuD',
+                'is_coinbase': False,
+                'num_sig': 1,
+                'prevout_hash': '3140eb24b43386f35ba69e3875eb6c93130ac66201d01c58f598defc949a5c2a',
+                'prevout_n': 0,
+                'pubkeys': ['02e61d176da16edd1d258a200ad9759ef63adf8e14cd97f53227bae35cdb84d2f6'],
+                'scriptSig': '01ff4c53ff0488b21e03ef2afea18000000089689bff23e1e7fb2f161daa37270a97a3d8c2e537584b2d304ecb47b86d21fc021b010d3bd425f8cf2e04824bfdf1f1f5ff1d51fadd9a41f9e3fb8dd3403b1bfe00000000',
+                'sequence': 4294967295,
+                'signatures': [None],
+                'x_pubkeys': ['ff0488b21e03ef2afea18000000089689bff23e1e7fb2f161daa37270a97a3d8c2e537584b2d304ecb47b86d21fc021b010d3bd425f8cf2e04824bfdf1f1f5ff1d51fadd9a41f9e3fb8dd3403b1bfe00000000']}],
+            'lockTime': 0,
+            'outputs': [{
+                'address': '14CHYaaByjJZpx4oHBpfDMdqhTyXnZ3kVs',
+                'prevout_n': 0,
+                'scriptPubKey': '76a914230ac37834073a42146f11ef8414ae929feaafc388ac',
+                'type': 'address',
+                'value': 1000000}],
+                'version': 1
+        }
+        tx = transaction.Transaction(unsigned_blob)
+        self.assertEquals(tx.deserialize(), expected)
+        self.assertEquals(tx.deserialize(), None)
+
+        self.assertEquals(tx.as_dict(), {'hex': unsigned_blob, 'complete': False})
+        self.assertEquals(tx.get_outputs(), [('14CHYaaByjJZpx4oHBpfDMdqhTyXnZ3kVs', 1000000)])
+        self.assertEquals(tx.get_output_addresses(), ['14CHYaaByjJZpx4oHBpfDMdqhTyXnZ3kVs'])
+
+        self.assertTrue(tx.has_address('14CHYaaByjJZpx4oHBpfDMdqhTyXnZ3kVs'))
+        self.assertTrue(tx.has_address('1446oU3z268EeFgfcwJv6X2VBXHfoYxfuD'))
+        self.assertFalse(tx.has_address('1CQj15y1N7LDHp7wTt28eoD1QhHgFgxECH'))
+
+        self.assertEquals(tx.inputs_to_sign(), set(x_pubkey for i in expected['inputs'] for x_pubkey in i['x_pubkeys']))
+        self.assertEquals(tx.serialize(), unsigned_blob)
+
+        tx.update_signatures(signed_blob)
+        self.assertEquals(tx.raw, signed_blob)
+
+        tx.update(unsigned_blob)
+        tx.raw = None
+        blob = str(tx)
+        self.assertEquals(transaction.deserialize(blob), expected)
+
+    def test_tx_signed(self):
+        expected = {
+            'inputs': [{
+                'address': '1446oU3z268EeFgfcwJv6X2VBXHfoYxfuD',
+                'is_coinbase': False,
+                'num_sig': 1,
+                'prevout_hash': '3140eb24b43386f35ba69e3875eb6c93130ac66201d01c58f598defc949a5c2a',
+                'prevout_n': 0,
+                'pubkeys': ['02e61d176da16edd1d258a200ad9759ef63adf8e14cd97f53227bae35cdb84d2f6'],
+                'scriptSig': '493046022100a82bbc57a0136751e5433f41cf000b3f1a99c6744775e76ec764fb78c54ee100022100f9e80b7de89de861dc6fb0c1429d5da72c2b6b2ee2406bc9bfb1beedd729d985012102e61d176da16edd1d258a200ad9759ef63adf8e14cd97f53227bae35cdb84d2f6',
+                'sequence': 4294967295,
+                'signatures': ['3046022100a82bbc57a0136751e5433f41cf000b3f1a99c6744775e76ec764fb78c54ee100022100f9e80b7de89de861dc6fb0c1429d5da72c2b6b2ee2406bc9bfb1beedd729d985'],
+                'x_pubkeys': ['02e61d176da16edd1d258a200ad9759ef63adf8e14cd97f53227bae35cdb84d2f6']}],
+            'lockTime': 0,
+            'outputs': [{
+                'address': '14CHYaaByjJZpx4oHBpfDMdqhTyXnZ3kVs',
+                'prevout_n': 0,
+                'scriptPubKey': '76a914230ac37834073a42146f11ef8414ae929feaafc388ac',
+                'type': 'address',
+                'value': 1000000}],
+            'version': 1
+        }
+        tx = transaction.Transaction(signed_blob)
+        self.assertEquals(tx.deserialize(), expected)
+        self.assertEquals(tx.deserialize(), None)
+        self.assertEquals(tx.as_dict(), {'hex': signed_blob, 'complete': True})
+
+        self.assertEquals(tx.inputs_to_sign(), set())
+        self.assertEquals(tx.serialize(), signed_blob)
+
+        tx.update_signatures(signed_blob)
+
+    def test_errors(self):
+        with self.assertRaises(TypeError):
+            transaction.Transaction.pay_script(output_type=None, addr='')
+
+        with self.assertRaises(BaseException):
+            transaction.parse_xpub('')
+
+    def test_parse_xpub(self):
+        res = transaction.parse_xpub('fe4e13b0f311a55b8a5db9a32e959da9f011b131019d4cebe6141b9e2c93edcbfc0954c358b062a9f94111548e50bde5847a3096b8b7872dcffadb0e9579b9017b01000200')
+        self.assertEquals(res, ('04ee98d63800824486a1cf5b4376f2f574d86e0a3009a6448105703453f3368e8e1d8d090aaecdd626a45cc49876709a3bbb6dc96a4311b3cac03e225df5f63dfc', '19h943e4diLc68GXW7G75QNe2KWuMu7BaJ'))
+
+        res = transaction.parse_xpub('fd007d260305ef27224bbcf6cf5238d2b3638b5a78d5')
+        self.assertEquals(res, (None, '1CQj15y1N7LDHp7wTt28eoD1QhHgFgxECH'))
+
+    def test_sign_tx(self):
+        tx = transaction.Transaction(unsigned_blob)
+        tx.deserialize()
+
+        x_pubkey = 'ff0488b21e03ef2afea18000000089689bff23e1e7fb2f161daa37270a97a3d8c2e537584b2d304ecb47b86d21fc021b010d3bd425f8cf2e04824bfdf1f1f5ff1d51fadd9a41f9e3fb8dd3403b1bfe00000000'
+        privkey = 'L187zmkzzGgf9QdB23MrZvwJ52WoZuQHtkddjmePtbVjXxicJND2'
+
+        tx.sign(keypairs={x_pubkey: privkey})
+        self.assertEquals(tx.serialize(), signed_blob)
+
+        tx.sign(keypairs={x_pubkey: privkey})
+        self.assertEquals(tx.serialize(), signed_blob)