diff --git a/squinnondation/messages.py b/squinnondation/messages.py
index 051ab58..5a68bec 100644
--- a/squinnondation/messages.py
+++ b/squinnondation/messages.py
@@ -83,6 +83,12 @@ class Pad1TLV(TLV):
         """
         return 1
 
+    @staticmethod
+    def construct() -> "Pad1TLV":
+        tlv = Pad1TLV()
+        tlv.type = 0
+        return tlv
+
 
 class PadNTLV(TLV):
     """
@@ -116,6 +122,13 @@ class PadNTLV(TLV):
         # TODO Add some easter eggs
         squirrel.add_system_message(f"I received {self.length} zeros, am I so a bag guy ? :cold_sweat:")
 
+    @staticmethod
+    def construct(length: int) -> "Pad1TLV":
+        tlv = PadNTLV()
+        tlv.type = 1
+        tlv.length = length
+        tlv.mbz = b'0'*length
+        return tlv
 
 class HelloTLV(TLV):
     type: int = 2
@@ -147,7 +160,7 @@ class HelloTLV(TLV):
         timeH = time.time()
         timeHL = None
         if not squirrel.is_active(sender) :
-            sender.id = source_id #The sender we are given misses an id
+            sender.id = self.source_id #The sender we are given misses an id
         else :
             timeHL = squirrel.activehazelnuts[(sender.address, sender.port)]
         if self.is_long and dest_id == squirrel.id :
@@ -165,6 +178,18 @@ class HelloTLV(TLV):
     def is_long(self) -> bool:
         return self.length == 16
 
+    @staticmethod
+    def construct(length: str, squirrel: Any) -> "HelloTLV":
+        tlv = HelloTLV()
+        tlv.type = 2
+        tlv.source_id = squirrel.id if squirrel else 0
+        if length == "short":
+            tlv.length = 8
+        else :
+            tlv.length = 16
+        tlv.dest_id = None
+        return tlv
+
 
 class NeighbourTLV(TLV):
     type: int = 3
@@ -189,6 +214,14 @@ class NeighbourTLV(TLV):
             squirrel.potentialhazelnuts[(ip_address, port)] = squirrel.new_hazel(ip_address, port)
         squirrel.add_system_message(f"New potential friend {self.ip_address}:{self.port}!")
 
+    @staticmethod
+    def construct(address: IPv6Address, port: int) -> "Pad1TLV":
+        tlv = NeighbourTLV()
+        tlv.type = 3
+        tlv.length = 18 #A priori...
+        tlv.ip_address = address
+        tlv.port = port
+        return tlv
 
 class DataTLV(TLV):
     type: int = 4
@@ -320,6 +353,14 @@ class GoAwayTLV(TLV):
             squirrel.potentialhazelnuts[(sender.address, sender.port)] = sender
         squirrel.add_system_message("Some told me that he went away : "+message)
 
+    @staticmethod
+    def construct(GAtype: GoAwayType, message: str) -> "Pad1TLV":
+        tlv = GoAwayTLV()
+        tlv.type = 6
+        tlv.code = GAtype
+        tlv.message = message.encode("UTF-8")
+        tlv.length = 1 + len(tlv.message)
+        return tlv
 
 class WarningTLV(TLV):
     type: int = 7