diff --git a/mix.exs b/mix.exs
index e335d76..d65bb19 100644
--- a/mix.exs
+++ b/mix.exs
@@ -10,7 +10,11 @@ defmodule PolicyService.MixProject do
       start_permanent: Mix.env() == :prod,
       aliases: aliases(),
       deps: deps(),
-      listeners: [Phoenix.CodeReloader]
+      listeners: [Phoenix.CodeReloader],
+      dialyzer: [
+        plt_file: {:no_warn, "priv/plts/dialyzer.plt"},
+        plt_add_apps: [:mix, :ex_unit]
+      ]
     ]
   end
 
@@ -56,7 +60,8 @@ defmodule PolicyService.MixProject do
       {:open_api_spex, "~> 3.20"},
       {:cors_plug, "~> 3.0"},
       {:flop, "~> 0.26"},
-      {:req, "~> 0.5"}
+      {:req, "~> 0.5"},
+      {:dialyxir, "~> 1.4", only: [:dev, :test], runtime: false}
     ]
   end
 
diff --git a/mix.lock b/mix.lock
index 2b42866..f296d37 100644
--- a/mix.lock
+++ b/mix.lock
@@ -10,9 +10,11 @@
   "credentials_obfuscation": {:hex, :credentials_obfuscation, "3.5.0", "61e282adfb4439486b3994faaec69543c7ee6cc7e70c6340e8853fd9deaf8219", [:rebar3], [], "hexpm", "843adbe3246861ce0f1a0fa3222f384834eb31defd8d6b9cba7afd2977c957bc"},
   "db_connection": {:hex, :db_connection, "2.9.0", "a6a97c5c958a2d7091a58a9be40caf41ab496b0701d21e1d1abff3fa27a7f371", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "17d502eacaf61829db98facf6f20808ed33da6ccf495354a41e64fe42f9c509c"},
   "decimal": {:hex, :decimal, "2.3.0", "3ad6255aa77b4a3c4f818171b12d237500e63525c2fd056699967a3e7ea20f62", [:mix], [], "hexpm", "a4d66355cb29cb47c3cf30e71329e58361cfcb37c34235ef3bf1d7bf3773aeac"},
+  "dialyxir": {:hex, :dialyxir, "1.4.7", "dda948fcee52962e4b6c5b4b16b2d8fa7d50d8645bbae8b8685c3f9ecb7f5f4d", [:mix], [{:erlex, ">= 0.2.8", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "b34527202e6eb8cee198efec110996c25c5898f43a4094df157f8d28f27d9efe"},
   "dns_cluster": {:hex, :dns_cluster, "0.2.0", "aa8eb46e3bd0326bd67b84790c561733b25c5ba2fe3c7e36f28e88f384ebcb33", [:mix], [], "hexpm", "ba6f1893411c69c01b9e8e8f772062535a4cf70f3f35bcc964a324078d8c8240"},
   "ecto": {:hex, :ecto, "3.13.5", "9d4a69700183f33bf97208294768e561f5c7f1ecf417e0fa1006e4a91713a834", [:mix], [{:decimal, "~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "df9efebf70cf94142739ba357499661ef5dbb559ef902b68ea1f3c1fabce36de"},
   "ecto_sql": {:hex, :ecto_sql, "3.13.4", "b6e9d07557ddba62508a9ce4a484989a5bb5e9a048ae0e695f6d93f095c25d60", [:mix], [{:db_connection, "~> 2.4.1 or ~> 2.5", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.13.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:myxql, "~> 0.7", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.19 or ~> 1.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:tds, "~> 2.1.1 or ~> 2.2", [hex: :tds, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "2b38cf0749ca4d1c5a8bcbff79bbe15446861ca12a61f9fba604486cb6b62a14"},
+  "erlex": {:hex, :erlex, "0.2.8", "cd8116f20f3c0afe376d1e8d1f0ae2452337729f68be016ea544a72f767d9c12", [:mix], [], "hexpm", "9d66ff9fedf69e49dc3fd12831e12a8a37b76f8651dd21cd45fcf5561a8a7590"},
   "eventstore": {:hex, :eventstore, "1.4.8", "26778c991cfb078f3906a4267060efc7bb5e5943f69ddb8ae6fb60f07042a66e", [:mix], [{:fsm, "~> 0.3", [hex: :fsm, repo: "hexpm", optional: false]}, {:gen_stage, "~> 1.2", [hex: :gen_stage, repo: "hexpm", optional: false]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.17", [hex: :postgrex, repo: "hexpm", optional: false]}], "hexpm", "30c914602fdea8db5992a90ecb1f84068531e764cf0c066be71ff0eec4e3bcb9"},
   "exconstructor": {:hex, :exconstructor, "1.3.1", "2c8b19b4702b195782e0cba46c7764df815c0beb8633383a9afb01199c47c3bd", [:mix], [], "hexpm", "5b7b2b043023e4643a44a66750d47587f01f3459d2fb4e7de05406b3a093fa6e"},
   "finch": {:hex, :finch, "0.21.0", "b1c3b2d48af02d0c66d2a9ebfb5622be5c5ecd62937cf79a88a7f98d48a8290c", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mint, "~> 1.6.2 or ~> 1.7", [hex: :mint, repo: "hexpm", optional: false]}, {:nimble_options, "~> 0.4 or ~> 1.0", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:nimble_pool, "~> 1.1", [hex: :nimble_pool, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "87dc6e169794cb2570f75841a19da99cfde834249568f2a5b121b809588a4377"},