diff --git a/lib/arc_ecto/schema.ex b/lib/arc_ecto/schema.ex
index 3b9a56c..df8465d 100644
--- a/lib/arc_ecto/schema.ex
+++ b/lib/arc_ecto/schema.ex
@@ -18,7 +18,7 @@ defmodule Arc.Ecto.Schema do
       end
 
       # Cast supports both atom and string keys, ensure we're matching on both.
-      allowed = Enum.map(allowed, fn key ->
+      cast_keys = Enum.map(allowed, fn key ->
         case key do
           key when is_binary(key) -> key
           key when is_atom(key) -> Atom.to_string(key)
@@ -31,7 +31,7 @@ defmodule Arc.Ecto.Schema do
         %{} ->
           params
           |> Arc.Ecto.Schema.convert_params_to_binary
-          |> Map.take(allowed)
+          |> Map.take(cast_keys)
           |> Enum.reduce([], fn
             # Don't wrap nil casts in the scope object
             {field, nil}, fields -> [{field, nil} | fields]
diff --git a/mix.exs b/mix.exs
index cfcb3c1..5dd5f59 100644
--- a/mix.exs
+++ b/mix.exs
@@ -4,15 +4,17 @@ defmodule Arc.Ecto.Mixfile do
   @version "0.11.0"
 
   def project do
-    [app: :arc_ecto,
-     version: @version,
-     elixir: "~> 1.4",
-     elixirc_paths: elixirc_paths(Mix.env),
-     deps: deps(),
-
-    # Hex
-     description: description(),
-     package: package()]
+    [
+      app: :arc_ecto,
+      version: @version,
+      elixir: "~> 1.4",
+      elixirc_paths: elixirc_paths(Mix.env()),
+      deps: deps(),
+
+      # Hex
+      description: description(),
+      package: package()
+    ]
   end
 
   # Configuration for the OTP application
@@ -24,7 +26,7 @@ defmodule Arc.Ecto.Mixfile do
 
   # Specifies which paths to compile per environment.
   defp elixirc_paths(:test), do: ["lib", "test/support"]
-  defp elixirc_paths(_),     do: ["lib"]
+  defp elixirc_paths(_), do: ["lib"]
 
   defp description do
     """
@@ -33,16 +35,18 @@ defmodule Arc.Ecto.Mixfile do
   end
 
   defp package do
-    [maintainers: ["Sean Stavropoulos"],
-     licenses: ["Apache 2.0"],
-     links: %{"GitHub" => "https://github.com/stavro/arc_ecto"},
-     files: ~w(mix.exs README.md lib)]
+    [
+      maintainers: ["Sean Stavropoulos"],
+      licenses: ["Apache 2.0"],
+      links: %{"GitHub" => "https://github.com/stavro/arc_ecto"},
+      files: ~w(mix.exs README.md lib)
+    ]
   end
 
   defp deps do
     [
-      {:arc,  "~> 0.11.0"},
-      {:ecto, "~> 2.1"},
+      {:arc, "~> 0.11.0"},
+      {:ecto, "~> 3.0.0"},
       {:mock, "~> 0.1.1", only: :test},
       {:ex_doc, ">= 0.0.0", only: :dev}
     ]
diff --git a/mix.lock b/mix.lock
index 3c832cc..aa96867 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,23 +1,20 @@
 %{
   "arc": {:hex, :arc, "0.11.0", "ac7a0cc03035317b6fef9fe94c97d7d9bd183a3e7ce1606aa0c175cfa8d1ba6d", [:mix], [{:ex_aws, "~> 2.0", [hex: :ex_aws, repo: "hexpm", optional: true]}, {:ex_aws_s3, "~> 2.0", [hex: :ex_aws_s3, repo: "hexpm", optional: true]}, {:hackney, "~> 1.0", [hex: :hackney, repo: "hexpm", optional: false]}, {:poison, "~> 2.2 or ~> 3.1", [hex: :poison, repo: "hexpm", optional: true]}, {:sweet_xml, "~> 0.6", [hex: :sweet_xml, repo: "hexpm", optional: true]}], "hexpm"},
   "certifi": {:hex, :certifi, "2.4.2", "75424ff0f3baaccfd34b1214184b6ef616d89e420b258bb0a5ea7d7bc628f7f0", [:rebar3], [{:parse_trans, "~>3.3", [hex: :parse_trans, repo: "hexpm", optional: false]}], "hexpm"},
-  "decimal": {:hex, :decimal, "1.4.0", "fac965ce71a46aab53d3a6ce45662806bdd708a4a95a65cde8a12eb0124a1333", [:mix], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.0.1", "2c2cd903bfdc3de3f189bd9a8d4569a075b88a8981ded9a0d95672f6e2b63141", [:mix], [], "hexpm"},
-  "ecto": {:hex, :ecto, "2.1.4", "d1ba932813ec0e0d9db481ef2c17777f1cefb11fc90fa7c142ff354972dfba7e", [:mix], [{:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: true]}, {:decimal, "~> 1.2", [hex: :decimal, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.8.0", [hex: :mariaex, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: false]}, {:postgrex, "~> 0.13.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
-  "erlcloud": {:hex, :erlcloud, "0.9.2"},
-  "ex_doc": {:hex, :ex_doc, "0.13.1", "658dbfc8cc5b0fac192f0f3254efe66ee6294200804a291549e0aeb052053bba", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"},
+  "decimal": {:hex, :decimal, "1.5.0", "b0433a36d0e2430e3d50291b1c65f53c37d56f83665b43d79963684865beab68", [:mix], [], "hexpm"},
+  "earmark": {:hex, :earmark, "1.2.6", "b6da42b3831458d3ecc57314dff3051b080b9b2be88c2e5aa41cd642a5b044ed", [:mix], [], "hexpm"},
+  "ecto": {:hex, :ecto, "3.0.0", "059250d96f17f9c10f524fcb09d058f566691343e90318a161cf62a48f3912a9", [:mix], [{:decimal, "~> 1.5", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: true]}], "hexpm"},
+  "ex_doc": {:hex, :ex_doc, "0.19.1", "519bb9c19526ca51d326c060cb1778d4a9056b190086a8c6c115828eaccea6cf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.7", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
   "hackney": {:hex, :hackney, "1.14.3", "b5f6f5dcc4f1fba340762738759209e21914516df6be440d85772542d4a5e412", [:rebar3], [{:certifi, "2.4.2", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "6.0.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "1.0.1", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "1.0.2", [hex: :mimerl, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "1.1.4", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}], "hexpm"},
-  "httpoison": {:hex, :httpoison, "0.13.0", "bfaf44d9f133a6599886720f3937a7699466d23bb0cd7a88b6ba011f53c6f562", [:mix], [{:hackney, "~> 1.8", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"},
   "idna": {:hex, :idna, "6.0.0", "689c46cbcdf3524c44d5f3dde8001f364cd7608a99556d8fbd8239a5798d4c10", [:rebar3], [{:unicode_util_compat, "0.4.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm"},
-  "jsx": {:hex, :jsx, "2.1.1"},
-  "lhttpc": {:hex, :lhttpc, "1.3.0"},
-  "meck": {:hex, :meck, "0.8.3", "4628a1334c69610c5bd558b04dc78d723d8ec5445c123856de34c77f462b5ee5", [:rebar], [], "hexpm"},
+  "makeup": {:hex, :makeup, "0.5.5", "9e08dfc45280c5684d771ad58159f718a7b5788596099bdfb0284597d368a882", [:mix], [{:nimble_parsec, "~> 0.4", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.10.0", "0f09c2ddf352887a956d84f8f7e702111122ca32fbbc84c2f0569b8b65cbf7fa", [:mix], [{:makeup, "~> 0.5.5", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm"},
+  "meck": {:hex, :meck, "0.8.12", "1f7b1a9f5d12c511848fec26bbefd09a21e1432eadb8982d9a8aceb9891a3cf2", [:rebar3], [], "hexpm"},
   "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm"},
   "mimerl": {:hex, :mimerl, "1.0.2", "993f9b0e084083405ed8252b99460c4f0563e41729ab42d9074fd5e52439be88", [:rebar3], [], "hexpm"},
-  "mock": {:hex, :mock, "0.1.1", "e21469ca27ba32aa7b18b61699db26f7a778171b21c0e5deb6f1218a53278574", [:mix], [{:meck, "~> 0.8.2", [hex: :meck, repo: "hexpm", optional: false]}], "hexpm"},
-  "mogrify": {:hex, :mogrify, "0.1.0"},
+  "mock": {:hex, :mock, "0.1.3", "657937b03f88fce89b3f7d6becc9f1ec1ac19c71081aeb32117db9bc4d9b3980", [:mix], [{:meck, "~> 0.8.2", [hex: :meck, repo: "hexpm", optional: false]}], "hexpm"},
+  "nimble_parsec": {:hex, :nimble_parsec, "0.4.0", "ee261bb53214943679422be70f1658fff573c5d0b0a1ecd0f18738944f818efe", [:mix], [], "hexpm"},
   "parse_trans": {:hex, :parse_trans, "3.3.0", "09765507a3c7590a784615cfd421d101aec25098d50b89d7aa1d66646bc571c1", [:rebar3], [], "hexpm"},
-  "poolboy": {:hex, :poolboy, "1.5.1", "6b46163901cfd0a1b43d692657ed9d7e599853b3b21b95ae5ae0a777cf9b6ca8", [:rebar], [], "hexpm"},
   "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.4", "f0eafff810d2041e93f915ef59899c923f4568f4585904d010387ed74988e77b", [:make, :mix, :rebar3], [], "hexpm"},
   "unicode_util_compat": {:hex, :unicode_util_compat, "0.4.1", "d869e4c68901dd9531385bb0c8c40444ebf624e60b6962d95952775cac5e90cd", [:rebar3], [], "hexpm"},
 }
diff --git a/test/definition_test.exs b/test/definition_test.exs
index ef1a062..5ac4dda 100644
--- a/test/definition_test.exs
+++ b/test/definition_test.exs
@@ -2,7 +2,7 @@ defmodule ArcTest.Ecto.Definition do
   use ExUnit.Case
 
   test "defines Definition.Type module" do
-    assert DummyDefinitionTwo.Type.type == Arc.Ecto.Type.type
+    assert DummyDefinitionTwo.Type.type() == Arc.Ecto.Type.type()
   end
 
   test "falls back to pre-defined url" do
@@ -11,18 +11,34 @@ defmodule ArcTest.Ecto.Definition do
 
   test "url appends timestamp to url with no query parameters" do
     updated_at = NaiveDateTime.from_erl!({{2015, 1, 1}, {1, 1, 1}})
-    url = DummyDefinitionTwo.url({%{file_name: "test.png", updated_at: updated_at}, :scope}, :original, [])
+
+    url =
+      DummyDefinitionTwo.url(
+        {%{file_name: "test.png", updated_at: updated_at}, :scope},
+        :original,
+        []
+      )
+
     assert url == "fallback?v=63587293261"
   end
 
   test "url appends timestamp to url with query parameters" do
     updated_at = NaiveDateTime.from_erl!({{2015, 1, 1}, {1, 1, 1}})
-    url = DummyDefinitionTwo.url({%{file_name: "test.png", updated_at: updated_at}, :scope}, :signed, [])
+
+    url =
+      DummyDefinitionTwo.url(
+        {%{file_name: "test.png", updated_at: updated_at}, :scope},
+        :signed,
+        []
+      )
+
     assert url == "fallback?a=1&b=2&v=63587293261"
   end
 
   test "url is unchanged if no timestamp is present" do
-    url = DummyDefinitionTwo.url({%{file_name: "test.png", updated_at: nil}, :scope}, :original, [])
+    url =
+      DummyDefinitionTwo.url({%{file_name: "test.png", updated_at: nil}, :scope}, :original, [])
+
     assert url == "fallback"
   end
 end
diff --git a/test/schema_test.exs b/test/schema_test.exs
index e921b24..350a0d1 100644
--- a/test/schema_test.exs
+++ b/test/schema_test.exs
@@ -84,7 +84,7 @@ defmodule ArcTest.Ecto.Schema do
   end
 
   test_with_mock "allow_paths => true", DummyDefinition, [store: fn({"/path/to/my/file.png", %TestUser{}}) -> {:ok, "file.png"} end] do
-    changeset = TestUser.path_changeset(%TestUser{}, %{"avatar" => "/path/to/my/file.png"})
+    TestUser.path_changeset(%TestUser{}, %{"avatar" => "/path/to/my/file.png"})
     assert called DummyDefinition.store({"/path/to/my/file.png", %TestUser{}})
   end
 end