diff --git a/lib/tesla/middleware/message_pack.ex b/lib/tesla/middleware/message_pack.ex
index 8f627840..e6ade1a8 100644
--- a/lib/tesla/middleware/message_pack.ex
+++ b/lib/tesla/middleware/message_pack.ex
@@ -59,9 +59,9 @@ defmodule Tesla.Middleware.MessagePack do
     with true <- encodable?(env),
          {:ok, body} <- encode_body(env.body, opts) do
       {:ok,
-        env
-        |> Tesla.put_body(body)
-        |> Tesla.put_headers([{"content-type", encode_content_type(opts)}])}
+       env
+       |> Tesla.put_body(body)
+       |> Tesla.put_headers([{"content-type", encode_content_type(opts)}])}
     else
       false -> {:ok, env}
       error -> error
@@ -71,7 +71,7 @@ defmodule Tesla.Middleware.MessagePack do
   defp encode_body(body, opts), do: process(body, :encode, opts)
 
   defp encode_content_type(opts),
-       do: Keyword.get(opts, :encode_content_type, @default_encode_content_type)
+    do: Keyword.get(opts, :encode_content_type, @default_encode_content_type)
 
   defp encodable?(%{body: nil}), do: false
   defp encodable?(%{body: body}) when is_binary(body), do: false
@@ -109,7 +109,7 @@ defmodule Tesla.Middleware.MessagePack do
   end
 
   defp content_types(opts),
-       do: @default_decode_content_types ++ Keyword.get(opts, :decode_content_types, [])
+    do: @default_decode_content_types ++ Keyword.get(opts, :decode_content_types, [])
 
   defp process(data, op, opts) do
     case do_process(data, op, opts) do
diff --git a/test/tesla/middleware/message_pack_test.exs b/test/tesla/middleware/message_pack_test.exs
index d0eb5bb3..aa4a7fc3 100644
--- a/test/tesla/middleware/message_pack_test.exs
+++ b/test/tesla/middleware/message_pack_test.exs
@@ -79,7 +79,8 @@ defmodule Tesla.Middleware.MessagePackTest do
     end
 
     test "return error when decoding invalid msgpack format" do
-      assert {:error, {Tesla.Middleware.MessagePack, :decode, _}} = Client.get("/invalid-msgpack-format")
+      assert {:error, {Tesla.Middleware.MessagePack, :decode, _}} =
+               Client.get("/invalid-msgpack-format")
     end
   end
 
@@ -93,7 +94,8 @@ defmodule Tesla.Middleware.MessagePackTest do
         {status, headers, body} =
           case env.url do
             "/decode" ->
-              {200, [{"content-type", "application/x-custom-msgpack"}], Msgpax.pack!(%{"value" => 123})}
+              {200, [{"content-type", "application/x-custom-msgpack"}],
+               Msgpax.pack!(%{"value" => 123})}
           end
 
         {:ok, %{env | status: status, headers: headers, body: body}}