diff --git a/src/Internal/Values/Vault.elm b/src/Internal/Values/Vault.elm
index 5153553..2725744 100644
--- a/src/Internal/Values/Vault.elm
+++ b/src/Internal/Values/Vault.elm
@@ -45,7 +45,7 @@ import Internal.Values.User as User exposing (User)
 type alias Vault =
     { accountData : Dict String Json.Value
     , rooms : Hashdict Room
-    , user : User
+    , user : Maybe User
     }
 
 
@@ -81,7 +81,7 @@ coder =
             , coder = Hashdict.coder .roomId Room.coder
             }
         )
-        (Json.field.required
+        (Json.field.optional.value
             { fieldName = "user"
             , toField = .user
             , description = Text.fields.vault.user
@@ -106,11 +106,11 @@ getAccountData key vault =
 
 {-| Initiate a new Vault type.
 -}
-init : User -> Vault
-init user =
+init : Maybe User -> Vault
+init mUser =
     { accountData = Dict.empty
     , rooms = Hashdict.empty .roomId
-    , user = user
+    , user = mUser
     }
 
 
@@ -156,4 +156,4 @@ update vu vault =
             setAccountData key value vault
 
         SetUser user ->
-            { vault | user = user }
+            { vault | user = Just user }
diff --git a/src/Matrix.elm b/src/Matrix.elm
index 0991107..f59136a 100644
--- a/src/Matrix.elm
+++ b/src/Matrix.elm
@@ -1,5 +1,5 @@
 module Matrix exposing
-    ( Vault, fromUserId
+    ( Vault, fromUserId, fromUsername
     , VaultUpdate, update
     , addAccessToken, sendMessageEvent
     )
@@ -19,7 +19,7 @@ support a monolithic public registry. (:
 
 ## Vault
 
-@docs Vault, fromUserId
+@docs Vault, fromUserId, fromUsername
 
 
 ## Keeping the Vault up-to-date
@@ -91,6 +91,27 @@ fromUserId uid =
         |> Maybe.map Vault
 
 
+{-| Using a username and an address, create a Vault.
+
+The username can either be the localpart or the full Matrix ID. For example,
+you can either insert `alice` or `@alice:example.org`.
+
+-}
+fromUsername : { username : String, host : String, port_ : Maybe Int } -> Vault
+fromUsername { username, host, port_ } =
+    { serverName =
+        port_
+            |> Maybe.map String.fromInt
+            |> Maybe.map ((++) ":")
+            |> Maybe.withDefault ""
+            |> (++) host
+    , content = Internal.init (User.fromString username)
+    }
+        |> Envelope.init
+        |> Envelope.mapContext (\c -> { c | username = Just username })
+        |> Vault
+
+
 {-| Send a message event to a room.
 
 This function can be used in a scenario where the user does not want to sync
@@ -99,15 +120,25 @@ exists and the user is able to send a message to, and instead just sends the
 request to the Matrix API.
 
 -}
-sendMessageEvent : Vault -> { content : E.Value, eventType : String, roomId : String, toMsg : VaultUpdate -> msg, transactionId : String } -> Cmd msg
-sendMessageEvent (Vault vault) data =
-    Api.sendMessageEvent vault
-        { content = data.content
-        , eventType = data.eventType
-        , roomId = data.roomId
-        , toMsg = Types.VaultUpdate >> data.toMsg
-        , transactionId = data.transactionId
-        }
+sendMessageEvent :
+    { content : E.Value
+    , eventType : String
+    , roomId : String
+    , toMsg : VaultUpdate -> msg
+    , transactionId : String
+    , vault : Vault
+    }
+    -> Cmd msg
+sendMessageEvent data =
+    case data.vault of
+        Vault vault ->
+            Api.sendMessageEvent vault
+                { content = data.content
+                , eventType = data.eventType
+                , roomId = data.roomId
+                , toMsg = Types.VaultUpdate >> data.toMsg
+                , transactionId = data.transactionId
+                }
 
 
 {-| Using new VaultUpdate information, update the Vault accordingly.
diff --git a/tests/Test/Values/Vault.elm b/tests/Test/Values/Vault.elm
index 96922a8..3982791 100644
--- a/tests/Test/Values/Vault.elm
+++ b/tests/Test/Values/Vault.elm
@@ -19,4 +19,4 @@ vault =
             |> Fuzz.map Dict.fromList
         )
         (TestHashdict.fuzzer .roomId TestRoom.fuzzer)
-        TestUser.fuzzer
+        (Fuzz.maybe TestUser.fuzzer)