diff --git a/CHANGELOG b/CHANGELOG
index d8813b8..a0dc11b 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+- 0.2.1
+	* Fix bug in wire format generation for tx
 - 0.2.0
 	* Consolidate genertic blcok, tx and tx result objects
 - 0.1.3
diff --git a/chainlib/block.py b/chainlib/block.py
index 93a20f7..32b91ca 100644
--- a/chainlib/block.py
+++ b/chainlib/block.py
@@ -19,7 +19,7 @@ class Block(Src):
  
     tx_generator = Tx
 
-    def __init__(self, src):
+    def __init__(self, src=None):
         self.number = None
         self.txs = []
         self.author = None
@@ -27,7 +27,7 @@ class Block(Src):
         self.get_tx = self.tx_index_by_hash
         self.tx = self.tx_by_index
 
-        super(Block, self).__init__(src)
+        super(Block, self).__init__(src=src)
 
 
     def tx_by_index(self, idx):
diff --git a/chainlib/tx.py b/chainlib/tx.py
index 505a5f7..266896f 100644
--- a/chainlib/tx.py
+++ b/chainlib/tx.py
@@ -28,8 +28,6 @@ class Tx(Src):
 
         self.result = None
     
-        self.generate_wire = self.wire
-
         super(Tx, self).__init__(src)
 
         if block != None:
@@ -61,9 +59,9 @@ class Tx(Src):
         return self.result.status.name
 
 
-    def wire(self):
-        raise NotImplementedError()
-
+    def generate_wire(self, chain_spec):
+        pass
+   
 
     def as_dict(self):
         raise NotImplementedError()
@@ -78,7 +76,7 @@ class Tx(Src):
 
 class TxResult(Src):
 
-    def __init__(self, src):
+    def __init__(self, src=None):
         self.status = Status.UNKNOWN
         self.tx_index = None
         self.block_hash = None
diff --git a/setup.cfg b/setup.cfg
index eca3099..2556118 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -3,7 +3,7 @@ name=chainlib
 license=WTFPL2
 author_email=dev@holbrook.no
 description=Generic blockchain access library and tooling
-version=0.2.0
+version=0.2.1
 url=https://gitlab.com/chaintools/chainlib
 author=Louis Holbrook