diff --git a/mix.exs b/mix.exs
index 4ab121e..885e8f6 100644
--- a/mix.exs
+++ b/mix.exs
@@ -60,6 +60,7 @@ defmodule MakerPassport.MixProject do
       {:jason, "~> 1.2"},
       {:dns_cluster, "~> 0.1.1"},
       {:plug_crypto, "~> 1.0"},
+      {:credo, "~> 1.7", only: [:dev, :test], runtime: false},
       {:bandit, "~> 1.5"}
     ]
   end
diff --git a/mix.lock b/mix.lock
index 6458726..ace3d8e 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,8 +1,10 @@
 %{
   "bandit": {:hex, :bandit, "1.5.7", "6856b1e1df4f2b0cb3df1377eab7891bec2da6a7fd69dc78594ad3e152363a50", [:mix], [{:hpax, "~> 1.0.0", [hex: :hpax, repo: "hexpm", optional: false]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}, {:thousand_island, "~> 1.0", [hex: :thousand_island, repo: "hexpm", optional: false]}, {:websock, "~> 0.5", [hex: :websock, repo: "hexpm", optional: false]}], "hexpm", "f2dd92ae87d2cbea2fa9aa1652db157b6cba6c405cb44d4f6dd87abba41371cd"},
   "bcrypt_elixir": {:hex, :bcrypt_elixir, "3.2.0", "feab711974beba4cb348147170346fe097eea2e840db4e012a145e180ed4ab75", [:make, :mix], [{:comeonin, "~> 5.3", [hex: :comeonin, repo: "hexpm", optional: false]}, {:elixir_make, "~> 0.6", [hex: :elixir_make, repo: "hexpm", optional: false]}], "hexpm", "563e92a6c77d667b19c5f4ba17ab6d440a085696bdf4c68b9b0f5b30bc5422b8"},
+  "bunt": {:hex, :bunt, "1.0.0", "081c2c665f086849e6d57900292b3a161727ab40431219529f13c4ddcf3e7a44", [:mix], [], "hexpm", "dc5f86aa08a5f6fa6b8096f0735c4e76d54ae5c9fa2c143e5a1fc7c1cd9bb6b5"},
   "castore": {:hex, :castore, "1.0.9", "5cc77474afadf02c7c017823f460a17daa7908e991b0cc917febc90e466a375c", [:mix], [], "hexpm", "5ea956504f1ba6f2b4eb707061d8e17870de2bee95fb59d512872c2ef06925e7"},
   "comeonin": {:hex, :comeonin, "5.5.0", "364d00df52545c44a139bad919d7eacb55abf39e86565878e17cebb787977368", [:mix], [], "hexpm", "6287fc3ba0aad34883cbe3f7949fc1d1e738e5ccdce77165bc99490aa69f47fb"},
+  "credo": {:hex, :credo, "1.7.10", "6e64fe59be8da5e30a1b96273b247b5cf1cc9e336b5fd66302a64b25749ad44d", [: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", "71fbc9a6b8be21d993deca85bf151df023a3097b01e09a2809d460348561d8cd"},
   "db_connection": {:hex, :db_connection, "2.7.0", "b99faa9291bb09892c7da373bb82cba59aefa9b36300f6145c5f201c7adf48ec", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "dcf08f31b2701f857dfc787fbad78223d61a32204f217f15e881dd93e4bdd3ff"},
   "decimal": {:hex, :decimal, "2.1.1", "5611dca5d4b2c3dd497dec8f68751f1f1a54755e8ed2a966c2633cf885973ad6", [:mix], [], "hexpm", "53cfe5f497ed0e7771ae1a475575603d77425099ba5faef9394932b35020ffcc"},
   "dns_cluster": {:hex, :dns_cluster, "0.1.3", "0bc20a2c88ed6cc494f2964075c359f8c2d00e1bf25518a6a6c7fd277c9b0c66", [:mix], [], "hexpm", "46cb7c4a1b3e52c7ad4cbe33ca5079fbde4840dedeafca2baf77996c2da1bc33"},