diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8ec2137..3d49ebf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [1.0.3] - 2024-02-19
+### Fixed
+- Upgrade dependencies to get rid of warnings with newer elixir. elixir 1.14 is the lowest supported version in mix.exs.
+
 ## [1.0.2] - 2022-02-14
 ### Fixed
 - Arguments with struct values are now passed through Jabbax instead of raising an error [@vtm9](https://github.com/vtm9).
@@ -35,6 +39,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 [Unreleased]: https://github.com/surgeventures/jabbax/compare/v1.0.2...HEAD
 
+[1.0.3]: https://github.com/surgeventures/jabbax/compare/v1.0.2...v1.0.3
 [1.0.2]: https://github.com/surgeventures/jabbax/compare/v1.0.1...v1.0.2
 [1.0.1]: https://github.com/surgeventures/jabbax/compare/v1.0.0...v1.0.1
 [1.0.1]: https://github.com/surgeventures/jabbax/compare/v0.2.1...v1.0.0
diff --git a/README.md b/README.md
index 4f3cf21..672e61a 100644
--- a/README.md
+++ b/README.md
@@ -197,8 +197,8 @@ Here's an example Jabbax config that you could add to your `config.exs`, along w
 
 ```elixir
 config :jabbax,
-  json_encoder: Poison,
-  json_decoder: Poison
+  json_encoder: Jason,
+  json_decoder: Jason
 ```
 
 ## License
diff --git a/config/config.exs b/config/config.exs
index d2d855e..46ec75b 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -1 +1 @@
-use Mix.Config
+require Config
diff --git a/lib/jabbax/deserializer.ex b/lib/jabbax/deserializer.ex
index 56fe0b6..efb09c5 100644
--- a/lib/jabbax/deserializer.ex
+++ b/lib/jabbax/deserializer.ex
@@ -54,9 +54,7 @@ defmodule Jabbax.Deserializer do
 
   defp deserialize_relationships(relationship_map)
        when is_map(relationship_map) or is_list(relationship_map) do
-    relationship_map
-    |> Enum.map(&deserialize_relationship_pair/1)
-    |> Enum.into(%{})
+    Map.new(relationship_map, &deserialize_relationship_pair/1)
   end
 
   defp deserialize_relationships(relationship),
@@ -107,9 +105,7 @@ defmodule Jabbax.Deserializer do
   defp dig_and_deserialize_links(_), do: %{}
 
   defp deserialize_links(link_map) do
-    link_map
-    |> Enum.map(&deserialize_link_pair/1)
-    |> Enum.into(%{})
+    Map.new(link_map, &deserialize_link_pair/1)
   end
 
   defp deserialize_link_pair({name, link}) do
@@ -195,9 +191,7 @@ defmodule Jabbax.Deserializer do
   defp deserialize_key_values(nil), do: %{}
 
   defp deserialize_key_values(key_values_map = %{}) do
-    key_values_map
-    |> Enum.map(&deserialize_key_value_pair/1)
-    |> Enum.into(%{})
+    Map.new(key_values_map, &deserialize_key_value_pair/1)
   end
 
   defp deserialize_key_value_pair({name, value}) do
diff --git a/lib/jabbax/serializer.ex b/lib/jabbax/serializer.ex
index c09f43a..03dd747 100644
--- a/lib/jabbax/serializer.ex
+++ b/lib/jabbax/serializer.ex
@@ -73,9 +73,7 @@ defmodule Jabbax.Serializer do
   defp serialize_relationships(relationship_map) when relationship_map == %{}, do: nil
 
   defp serialize_relationships(relationship_map = %{}) do
-    relationship_map
-    |> Enum.map(&serialize_relationship_pair/1)
-    |> Enum.into(%{})
+    Map.new(relationship_map, &serialize_relationship_pair/1)
   end
 
   defp serialize_relationships(arg) do
@@ -113,9 +111,7 @@ defmodule Jabbax.Serializer do
   defp serialize_links(link_map) when link_map == %{}, do: nil
 
   defp serialize_links(link_map = %{}) do
-    link_map
-    |> Enum.map(&serialize_link_pair/1)
-    |> Enum.into(%{})
+    Map.new(link_map, &serialize_link_pair/1)
   end
 
   defp serialize_links(arg) do
@@ -219,9 +215,7 @@ defmodule Jabbax.Serializer do
   defp serialize_key_values(key_values_map) when key_values_map == %{}, do: nil
 
   defp serialize_key_values(key_values_map = %{}) do
-    key_values_map
-    |> Enum.map(&serialize_key_value_pair/1)
-    |> Enum.into(%{})
+    Map.new(key_values_map, &serialize_key_value_pair/1)
   end
 
   defp serialize_key_values(arg) do
@@ -247,8 +241,7 @@ defmodule Jabbax.Serializer do
   defp struct_to_map_with_present_keys(struct = %{}) do
     struct
     |> Map.from_struct()
-    |> Enum.filter(fn {_, value} -> value != nil end)
-    |> Enum.into(%{})
+    |> Map.filter(fn {_, value} -> value != nil end)
   end
 
   defp put_empty_data(doc = %{data: _}), do: doc
diff --git a/mix.exs b/mix.exs
index 8ffa9f4..c68562f 100644
--- a/mix.exs
+++ b/mix.exs
@@ -4,8 +4,8 @@ defmodule Jabbax.Mixfile do
   def project do
     [
       app: :jabbax,
-      version: "1.0.2",
-      elixir: "~> 1.4",
+      version: "1.0.3",
+      elixir: "~> 1.14",
       build_embedded: Mix.env() == :prod,
       start_permanent: Mix.env() == :prod,
       deps: deps(),
@@ -33,16 +33,16 @@ defmodule Jabbax.Mixfile do
   end
 
   def application do
-    [extra_applications: [:logger], env: [json_encoder: Poison, json_decoder: Poison]]
+    [extra_applications: [:logger], env: [json_encoder: Jason, json_decoder: Jason]]
   end
 
   defp deps do
     [
-      {:credo, "~> 1.5", only: [:dev, :test], runtime: false},
+      {:credo, "~> 1.6", only: [:dev, :test], runtime: false},
       {:ex_doc, ">= 0.0.0", only: :dev, runtime: false},
       {:dialyxir, "~> 1.0", only: [:dev, :test], runtime: false},
       {:plug, "~> 1.12", optional: true},
-      {:poison, "~> 3.0", optional: true}
+      {:jason, "~> 1.0", optional: true}
     ]
   end
 end
diff --git a/mix.lock b/mix.lock
index 0a299fb..abf9571 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,19 +1,18 @@
 %{
-  "bunt": {:hex, :bunt, "0.2.0", "951c6e801e8b1d2cbe58ebbd3e616a869061ddadcc4863d0a2182541acae9a38", [:mix], [], "hexpm", "7af5c7e09fe1d40f76c8e4f9dd2be7cebd83909f31fee7cd0e9eadc567da8353"},
-  "credo": {:hex, :credo, "1.5.6", "e04cc0fdc236fefbb578e0c04bd01a471081616e741d386909e527ac146016c6", [:mix], [{:bunt, "~> 0.2.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2.8", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "4b52a3e558bd64e30de62a648518a5ea2b6e3e5d2b164ef5296244753fc7eb17"},
-  "dialyxir": {:hex, :dialyxir, "1.1.0", "c5aab0d6e71e5522e77beff7ba9e08f8e02bad90dfbeffae60eaf0cb47e29488", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "07ea8e49c45f15264ebe6d5b93799d4dd56a44036cf42d0ad9c960bc266c0b9a"},
-  "earmark_parser": {:hex, :earmark_parser, "1.4.13", "0c98163e7d04a15feb62000e1a891489feb29f3d10cb57d4f845c405852bbef8", [:mix], [], "hexpm", "d602c26af3a0af43d2f2645613f65841657ad6efc9f0e361c3b6c06b578214ba"},
+  "bunt": {:hex, :bunt, "1.0.0", "081c2c665f086849e6d57900292b3a161727ab40431219529f13c4ddcf3e7a44", [:mix], [], "hexpm", "dc5f86aa08a5f6fa6b8096f0735c4e76d54ae5c9fa2c143e5a1fc7c1cd9bb6b5"},
+  "credo": {:hex, :credo, "1.7.4", "68ca5cf89071511c12fd9919eb84e388d231121988f6932756596195ccf7fd35", [:mix], [{:bunt, "~> 0.2.1 or ~> 1.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2 or ~> 1.0", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "9cf776d062c78bbe0f0de1ecaee183f18f2c3ec591326107989b054b7dddefc2"},
+  "dialyxir": {:hex, :dialyxir, "1.4.3", "edd0124f358f0b9e95bfe53a9fcf806d615d8f838e2202a9f430d59566b6b53b", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "bf2cfb75cd5c5006bec30141b131663299c661a864ec7fbbc72dfa557487a986"},
+  "earmark_parser": {:hex, :earmark_parser, "1.4.39", "424642f8335b05bb9eb611aa1564c148a8ee35c9c8a8bba6e129d51a3e3c6769", [:mix], [], "hexpm", "06553a88d1f1846da9ef066b87b57c6f605552cfbe40d20bd8d59cc6bde41944"},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
-  "ex_doc": {:hex, :ex_doc, "0.24.2", "e4c26603830c1a2286dae45f4412a4d1980e1e89dc779fcd0181ed1d5a05c8d9", [:mix], [{:earmark_parser, "~> 1.4.0", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "e134e1d9e821b8d9e4244687fb2ace58d479b67b282de5158333b0d57c6fb7da"},
-  "file_system": {:hex, :file_system, "0.2.10", "fb082005a9cd1711c05b5248710f8826b02d7d1784e7c3451f9c1231d4fc162d", [:mix], [], "hexpm", "41195edbfb562a593726eda3b3e8b103a309b733ad25f3d642ba49696bf715dc"},
-  "jason": {:hex, :jason, "1.2.2", "ba43e3f2709fd1aa1dce90aaabfd039d000469c05c56f0b8e31978e03fa39052", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "18a228f5f0058ee183f29f9eae0805c6e59d61c3b006760668d8d18ff0d12179"},
-  "makeup": {:hex, :makeup, "1.0.5", "d5a830bc42c9800ce07dd97fa94669dfb93d3bf5fcf6ea7a0c67b2e0e4a7f26c", [:mix], [{:nimble_parsec, "~> 0.5 or ~> 1.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "cfa158c02d3f5c0c665d0af11512fed3fba0144cf1aadee0f2ce17747fba2ca9"},
-  "makeup_elixir": {:hex, :makeup_elixir, "0.15.1", "b5888c880d17d1cc3e598f05cdb5b5a91b7b17ac4eaf5f297cb697663a1094dd", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.1", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "db68c173234b07ab2a07f645a5acdc117b9f99d69ebf521821d89690ae6c6ec8"},
-  "makeup_erlang": {:hex, :makeup_erlang, "0.1.1", "3fcb7f09eb9d98dc4d208f49cc955a34218fc41ff6b84df7c75b3e6e533cc65f", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "174d0809e98a4ef0b3309256cbf97101c6ec01c4ab0b23e926a9e17df2077cbb"},
-  "mime": {:hex, :mime, "2.0.1", "0de4c81303fe07806ebc2494d5321ce8fb4df106e34dd5f9d787b637ebadc256", [:mix], [], "hexpm", "7a86b920d2aedce5fb6280ac8261ac1a739ae6c1a1ad38f5eadf910063008942"},
-  "nimble_parsec": {:hex, :nimble_parsec, "1.1.0", "3a6fca1550363552e54c216debb6a9e95bd8d32348938e13de5eda962c0d7f89", [:mix], [], "hexpm", "08eb32d66b706e913ff748f11694b17981c0b04a33ef470e33e11b3d3ac8f54b"},
-  "plug": {:hex, :plug, "1.12.1", "645678c800601d8d9f27ad1aebba1fdb9ce5b2623ddb961a074da0b96c35187d", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "d57e799a777bc20494b784966dc5fbda91eb4a09f571f76545b72a634ce0d30b"},
-  "plug_crypto": {:hex, :plug_crypto, "1.2.2", "05654514ac717ff3a1843204b424477d9e60c143406aa94daf2274fdd280794d", [:mix], [], "hexpm", "87631c7ad914a5a445f0a3809f99b079113ae4ed4b867348dd9eec288cecb6db"},
-  "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm", "fec8660eb7733ee4117b85f55799fd3833eb769a6df71ccf8903e8dc5447cfce"},
-  "telemetry": {:hex, :telemetry, "1.0.0", "0f453a102cdf13d506b7c0ab158324c337c41f1cc7548f0bc0e130bbf0ae9452", [:rebar3], [], "hexpm", "73bc09fa59b4a0284efb4624335583c528e07ec9ae76aca96ea0673850aec57a"},
+  "ex_doc": {:hex, :ex_doc, "0.31.1", "8a2355ac42b1cc7b2379da9e40243f2670143721dd50748bf6c3b1184dae2089", [:mix], [{:earmark_parser, "~> 1.4.39", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_c, ">= 0.1.1", [hex: :makeup_c, repo: "hexpm", optional: true]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "3178c3a407c557d8343479e1ff117a96fd31bafe52a039079593fb0524ef61b0"},
+  "file_system": {:hex, :file_system, "1.0.0", "b689cc7dcee665f774de94b5a832e578bd7963c8e637ef940cd44327db7de2cd", [:mix], [], "hexpm", "6752092d66aec5a10e662aefeed8ddb9531d79db0bc145bb8c40325ca1d8536d"},
+  "jason": {:hex, :jason, "1.4.1", "af1504e35f629ddcdd6addb3513c3853991f694921b1b9368b0bd32beb9f1b63", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "fbb01ecdfd565b56261302f7e1fcc27c4fb8f32d56eab74db621fc154604a7a1"},
+  "makeup": {:hex, :makeup, "1.1.1", "fa0bc768698053b2b3869fa8a62616501ff9d11a562f3ce39580d60860c3a55e", [:mix], [{:nimble_parsec, "~> 1.2.2 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "5dc62fbdd0de44de194898b6710692490be74baa02d9d108bc29f007783b0b48"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.16.1", "cc9e3ca312f1cfeccc572b37a09980287e243648108384b97ff2b76e505c3555", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.2.3 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "e127a341ad1b209bd80f7bd1620a15693a9908ed780c3b763bccf7d200c767c6"},
+  "makeup_erlang": {:hex, :makeup_erlang, "0.1.4", "29563475afa9b8a2add1b7a9c8fb68d06ca7737648f28398e04461f008b69521", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "f4ed47ecda66de70dd817698a703f8816daa91272e7e45812469498614ae8b29"},
+  "mime": {:hex, :mime, "2.0.5", "dc34c8efd439abe6ae0343edbb8556f4d63f178594894720607772a041b04b02", [:mix], [], "hexpm", "da0d64a365c45bc9935cc5c8a7fc5e49a0e0f9932a761c55d6c52b142780a05c"},
+  "nimble_parsec": {:hex, :nimble_parsec, "1.4.0", "51f9b613ea62cfa97b25ccc2c1b4216e81df970acd8e16e8d1bdc58fef21370d", [:mix], [], "hexpm", "9c565862810fb383e9838c1dd2d7d2c437b3d13b267414ba6af33e50d2d1cf28"},
+  "plug": {:hex, :plug, "1.15.3", "712976f504418f6dff0a3e554c40d705a9bcf89a7ccef92fc6a5ef8f16a30a97", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "cc4365a3c010a56af402e0809208873d113e9c38c401cabd88027ef4f5c01fd2"},
+  "plug_crypto": {:hex, :plug_crypto, "2.0.0", "77515cc10af06645abbfb5e6ad7a3e9714f805ae118fa1a70205f80d2d70fe73", [:mix], [], "hexpm", "53695bae57cc4e54566d993eb01074e4d894b65a3766f1c43e2c61a1b0f45ea9"},
+  "telemetry": {:hex, :telemetry, "1.2.1", "68fdfe8d8f05a8428483a97d7aab2f268aaff24b49e0f599faa091f1d4e7f61c", [:rebar3], [], "hexpm", "dad9ce9d8effc621708f99eac538ef1cbe05d6a874dd741de2e689c47feafed5"},
 }
diff --git a/test/jabbax/parser_test.exs b/test/jabbax/parser_test.exs
index 244218e..a7c3cb4 100644
--- a/test/jabbax/parser_test.exs
+++ b/test/jabbax/parser_test.exs
@@ -3,24 +3,26 @@ defmodule Jabbax.ParserTest do
   use Plug.Test
   use Jabbax.Document
 
-  @sample_json %{
-    "data" => %{
-      "id" => "1",
-      "type" => "user",
-      "attributes" => %{
-        "name" => "Sample User"
+  @sample_json """
+  {
+    "data": {
+      "id": "1",
+      "type": "user",
+      "attributes": {
+        "name": "Sample User"
       }
     },
-    "jsonapi" => %{
-      "version" => "1.0"
+    "jsonapi": {
+      "version": "1.0"
     }
   }
+  """
 
   def parse(conn, opts \\ []) do
     opts =
       opts
       |> Keyword.put_new(:parsers, [Jabbax.Parser])
-      |> Keyword.put_new(:json_decoder, Poison)
+      |> Keyword.put_new(:json_decoder, Jason)
 
     Plug.Parsers.call(conn, Plug.Parsers.init(opts))
   end
@@ -28,17 +30,25 @@ defmodule Jabbax.ParserTest do
   test "JSON API document" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/vnd.api+json")
       |> parse()
 
-    assert connection.body_params == @sample_json
+    assert connection.body_params ==
+             %{
+               "data" => %{
+                 "attributes" => %{"name" => "Sample User"},
+                 "id" => "1",
+                 "type" => "user"
+               },
+               "jsonapi" => %{"version" => "1.0"}
+             }
   end
 
   test "plain JSON content type without JSON parser" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/json")
 
     assert_raise(Plug.Parsers.UnsupportedMediaTypeError, fn ->
@@ -49,7 +59,7 @@ defmodule Jabbax.ParserTest do
   test "no content type" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> parse()
 
     assert connection.body_params == %{}
@@ -75,7 +85,7 @@ defmodule Jabbax.ParserTest do
   test "custom body_reader" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/vnd.api+json")
       |> parse(body_reader: {BodyReader, :read_body, []})
 
diff --git a/test/jabbax/plug_test.exs b/test/jabbax/plug_test.exs
index 2fec4a3..b635dd0 100644
--- a/test/jabbax/plug_test.exs
+++ b/test/jabbax/plug_test.exs
@@ -3,18 +3,20 @@ defmodule Jabbax.PlugTest do
   use Plug.Test
   use Jabbax.Document
 
-  @sample_json %{
-    "data" => %{
-      "id" => "1",
-      "type" => "user",
-      "attributes" => %{
-        "name" => "Sample User"
+  @sample_json """
+  {
+    "data": {
+      "id": "1",
+      "type": "user",
+      "attributes": {
+        "name": "Sample User"
       }
     },
-    "jsonapi" => %{
-      "version" => "1.0"
+    "jsonapi": {
+      "version": "1.0"
     }
   }
+  """
 
   @sample_doc %Document{
     data: %Resource{
@@ -28,13 +30,13 @@ defmodule Jabbax.PlugTest do
   }
 
   def parse(conn, parsers) do
-    Plug.Parsers.call(conn, Plug.Parsers.init(parsers: parsers, json_decoder: Poison))
+    Plug.Parsers.call(conn, Plug.Parsers.init(parsers: parsers, json_decoder: Jason))
   end
 
   test "JSON API document" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/vnd.api+json")
       |> parse([Jabbax.Parser])
       |> Jabbax.Plug.call(Jabbax.Plug.init(nil))
@@ -45,7 +47,7 @@ defmodule Jabbax.PlugTest do
   test "JSON API document with custom assign name" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/vnd.api+json")
       |> parse([Jabbax.Parser])
       |> Jabbax.Plug.call(Jabbax.Plug.init(assign: :custom_doc))
@@ -56,7 +58,7 @@ defmodule Jabbax.PlugTest do
   test "other content type" do
     connection =
       :post
-      |> conn("/", Poison.encode!(@sample_json))
+      |> conn("/", @sample_json)
       |> put_req_header("content-type", "application/json")
       |> parse([:json, Jabbax.Parser])
       |> Jabbax.Plug.call(Jabbax.Plug.init(nil))
@@ -65,26 +67,28 @@ defmodule Jabbax.PlugTest do
   end
 
   test "malformed body" do
-    malformed_body = %{
-      "data" => %{
-        "type" => "employees",
-        "relationships" => %{
-          "service" => %{
-            "dataaa" => %{
-              "type" => "services",
-              "id" => "21"
+    malformed_body = """
+      {
+      "data": {
+        "type": "employees",
+        "relationships": {
+          "service": {
+            "dataaa": {
+              "type": "services",
+              "id": "21"
             }
           }
         }
       },
-      "jsonapi" => %{
-        "version" => "1.0"
+      "jsonapi": {
+        "version": "1.0"
       }
     }
+    """
 
     assert_raise(Plug.Parsers.ParseError, fn ->
       :post
-      |> conn("/", Poison.encode!(malformed_body))
+      |> conn("/", malformed_body)
       |> put_req_header("content-type", "application/vnd.api+json")
       |> parse([Jabbax.Parser])
       |> Jabbax.Plug.call(Jabbax.Plug.init(nil))
diff --git a/test/jabbax_test.exs b/test/jabbax_test.exs
index c12f517..dd9fda6 100644
--- a/test/jabbax_test.exs
+++ b/test/jabbax_test.exs
@@ -10,6 +10,6 @@ defmodule JabbaxTest do
 
   test "encode!" do
     assert Jabbax.encode!(%Document{}) ==
-             ~s({"jsonapi":{"version":"1.0"},"data":null})
+             ~s({"data":null,"jsonapi":{"version":"1.0"}})
   end
 end