diff --git a/.travis.yml b/.travis.yml
index ddba822..a9cee96 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,7 +22,9 @@ jobs:
     - stage: format
       env:
         - MIX_ENV=dev
-      script: mix format --check-formatted
+      script:
+        mix format --check-formatted
+        mix credo
       elixir: 1.6
     - stage: types
       env:
diff --git a/mix.exs b/mix.exs
index f3d3c84..d001596 100644
--- a/mix.exs
+++ b/mix.exs
@@ -13,7 +13,12 @@ defmodule Hunter.Mixfile do
       build_embedded: Mix.env() == :prod,
       start_permanent: Mix.env() == :prod,
       elixirc_paths: ["lib"],
-      deps: deps()
+      deps: deps(),
+      dialyzer: [
+        plt_add_apps: [:mix, :ex_unit],
+        check_plt: true,
+        flags: [:error_handling, :race_conditions, :underspecs]
+      ]
     ]
   end
 
@@ -31,7 +36,8 @@ defmodule Hunter.Mixfile do
       {:poison, "~> 4.0"},
       {:ex_doc, "~> 0.14", only: :dev, runtime: false},
       {:dialyxir, "~> 1.0.0-rc.3", only: :dev, runtime: false},
-      {:mox, "~> 0.5", only: :test}
+      {:mox, "~> 0.5", only: :test},
+      {:credo, "~> 1.0.0", only: [:dev, :test], runtime: false}
     ]
   end
 
diff --git a/mix.lock b/mix.lock
index a77e218..282c368 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,5 +1,7 @@
 %{
+  "bunt": {:hex, :bunt, "0.2.0", "951c6e801e8b1d2cbe58ebbd3e616a869061ddadcc4863d0a2182541acae9a38", [:mix], [], "hexpm"},
   "certifi": {:hex, :certifi, "2.4.2", "75424ff0f3baaccfd34b1214184b6ef616d89e420b258bb0a5ea7d7bc628f7f0", [:rebar3], [{:parse_trans, "~>3.3", [hex: :parse_trans, repo: "hexpm", optional: false]}], "hexpm"},
+  "credo": {:hex, :credo, "1.0.3", "5278e8953f379b41ebe27c75c96d2e154ebc3f75dfe057c8b68c39133c25bb9f", [:mix], [{:bunt, "~> 0.2.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm"},
   "dialyxir": {:hex, :dialyxir, "1.0.0-rc.4", "71b42f5ee1b7628f3e3a6565f4617dfb02d127a0499ab3e72750455e986df001", [:mix], [{:erlex, "~> 0.1", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm"},
   "earmark": {:hex, :earmark, "1.3.1", "73812f447f7a42358d3ba79283cfa3075a7580a3a2ed457616d6517ac3738cb9", [:mix], [], "hexpm"},
   "erlex": {:hex, :erlex, "0.2.1", "cee02918660807cbba9a7229cae9b42d1c6143b768c781fa6cee1eaf03ad860b", [:mix], [], "hexpm"},
@@ -7,6 +9,7 @@
   "hackney": {:hex, :hackney, "1.15.0", "287a5d2304d516f63e56c469511c42b016423bcb167e61b611f6bad47e3ca60e", [: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, "1.5.0", "71ae9f304bdf7f00e9cd1823f275c955bdfc68282bc5eb5c85c3a9ade865d68e", [: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"},
+  "jason": {:hex, :jason, "1.1.2", "b03dedea67a99223a2eaf9f1264ce37154564de899fd3d8b9a21b1a6fd64afe7", [:mix], [{:decimal, "~> 1.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm"},
   "makeup": {:hex, :makeup, "0.8.0", "9cf32aea71c7fe0a4b2e9246c2c4978f9070257e5c9ce6d4a28ec450a839b55f", [:mix], [{:nimble_parsec, "~> 0.5.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
   "makeup_elixir": {:hex, :makeup_elixir, "0.13.0", "be7a477997dcac2e48a9d695ec730b2d22418292675c75aa2d34ba0909dcdeda", [:mix], [{:makeup, "~> 0.8", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm"},
   "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], []},