diff --git a/mix.exs b/mix.exs
index 7934fe95..21612a80 100644
--- a/mix.exs
+++ b/mix.exs
@@ -72,7 +72,7 @@ defmodule SignDict.Mixfile do
       {:exq_ui, "~> 0.11.0"},
       {:exq, "~> 0.11"},
       {:gettext, "~> 0.13"},
-      {:guardian, "~> 2.2.0"},
+      {:guardian, "~> 2.3.1"},
       {:mix_test_watch, "~> 1.0", only: :dev, runtime: false},
       {:phoenix_ecto, "~> 4.0"},
       {:ecto_sql, "~> 3.0"},
diff --git a/mix.lock b/mix.lock
index 9806eb8c..1c69c704 100644
--- a/mix.lock
+++ b/mix.lock
@@ -44,7 +44,7 @@
   "file_system": {:hex, :file_system, "0.2.10", "fb082005a9cd1711c05b5248710f8826b02d7d1784e7c3451f9c1231d4fc162d", [:mix], [], "hexpm", "41195edbfb562a593726eda3b3e8b103a309b733ad25f3d642ba49696bf715dc"},
   "gen_smtp": {:hex, :gen_smtp, "1.1.0", "b0c92138f69e2f73e1eb791075e93e952efcbc231a536740749b02a1a57155a3", [:rebar3], [{:hut, "1.3.0", [hex: :hut, repo: "hexpm", optional: false]}, {:ranch, ">= 1.7.0", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "e53a13c4bb662331bdf4aa47f00982ef49ce2b4e5c703240542cb7b28f23546a"},
   "gettext": {:hex, :gettext, "0.19.1", "564953fd21f29358e68b91634799d9d26989f8d039d7512622efb3c3b1c97892", [:mix], [], "hexpm", "10c656c0912b8299adba9b061c06947511e3f109ab0d18b44a866a4498e77222"},
-  "guardian": {:hex, :guardian, "2.2.4", "3dafdc19665411c96b2796d184064d691bc08813a132da5119e39302a252b755", [:mix], [{:jose, "~> 1.8", [hex: :jose, repo: "hexpm", optional: false]}, {:plug, "~> 1.3.3 or ~> 1.4", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "6f83d4309c16ec2469da8606bb2a9815512cc2fac1595ad34b79940a224eb110"},
+  "guardian": {:hex, :guardian, "2.3.1", "2b2d78dc399a7df182d739ddc0e566d88723299bfac20be36255e2d052fd215d", [:mix], [{:jose, "~> 1.8", [hex: :jose, repo: "hexpm", optional: false]}, {:plug, "~> 1.3.3 or ~> 1.4", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "bbe241f9ca1b09fad916ad42d6049d2600bbc688aba5b3c4a6c82592a54274c3"},
   "hackney": {:hex, :hackney, "1.18.1", "f48bf88f521f2a229fc7bae88cf4f85adc9cd9bcf23b5dc8eb6a1788c662c4f6", [:rebar3], [{:certifi, "~>2.9.0", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "~>6.1.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "~>1.0.0", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "~>1.1", [hex: :mimerl, repo: "hexpm", optional: false]}, {:parse_trans, "3.3.1", [hex: :parse_trans, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "~>1.1.0", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}, {:unicode_util_compat, "~>0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "a4ecdaff44297e9b5894ae499e9a070ea1888c84afdd1fd9b7b2bc384950128e"},
   "httpoison": {:hex, :httpoison, "1.8.2", "9eb9c63ae289296a544842ef816a85d881d4a31f518a0fec089aaa744beae290", [:mix], [{:hackney, "~> 1.17", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm", "2bb350d26972e30c96e2ca74a1aaf8293d61d0742ff17f01e0279fef11599921"},
   "hut": {:hex, :hut, "1.3.0", "71f2f054e657c03f959cf1acc43f436ea87580696528ca2a55c8afb1b06c85e7", [:"erlang.mk", :rebar, :rebar3], [], "hexpm", "7e15d28555d8a1f2b5a3a931ec120af0753e4853a4c66053db354f35bf9ab563"},
@@ -64,7 +64,7 @@
   "phoenix_pubsub": {:hex, :phoenix_pubsub, "1.1.2", "496c303bdf1b2e98a9d26e89af5bba3ab487ba3a3735f74bf1f4064d2a845a3e", [:mix], [], "hexpm", "1f13f9f0f3e769a667a6b6828d29dec37497a082d195cc52dbef401a9b69bf38"},
   "plug": {:hex, :plug, "1.13.6", "187beb6b67c6cec50503e940f0434ea4692b19384d47e5fdfd701e93cadb4cc2", [: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", "02b9c6b9955bce92c829f31d6284bf53c591ca63c4fb9ff81dfd0418667a34ff"},
   "plug_cowboy": {:hex, :plug_cowboy, "2.5.2", "62894ccd601cf9597e2c23911ff12798a8a18d237e9739f58a6b04e4988899fe", [:mix], [{:cowboy, "~> 2.7", [hex: :cowboy, repo: "hexpm", optional: false]}, {:cowboy_telemetry, "~> 0.3", [hex: :cowboy_telemetry, repo: "hexpm", optional: false]}, {:plug, "~> 1.7", [hex: :plug, repo: "hexpm", optional: false]}], "hexpm", "ea6e87f774c8608d60c8d34022a7d073bd7680a0a013f049fc62bf35efea1044"},
-  "plug_crypto": {:hex, :plug_crypto, "1.2.2", "05654514ac717ff3a1843204b424477d9e60c143406aa94daf2274fdd280794d", [:mix], [], "hexpm", "87631c7ad914a5a445f0a3809f99b079113ae4ed4b867348dd9eec288cecb6db"},
+  "plug_crypto": {:hex, :plug_crypto, "1.2.3", "8f77d13aeb32bfd9e654cb68f0af517b371fb34c56c9f2b58fe3df1235c1251a", [:mix], [], "hexpm", "b5672099c6ad5c202c45f5a403f21a3411247f164e4a8fab056e5cd8a290f4a2"},
   "plugsnag": {:hex, :plugsnag, "1.6.1", "4d051770bc0835f66175bb0cc7b507b5002815024066fdaa7f2a7e2bf8cb34d1", [:mix], [{:bugsnag, "~> 1.3 or ~> 2.0 or ~> 3.0", [hex: :bugsnag, repo: "hexpm", optional: false]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: false]}], "hexpm", "65cdce8ed718b10346d9ac9e063aa55a28fff7c554fccb8aff3cf38b4d4620b3"},
   "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm", "fec8660eb7733ee4117b85f55799fd3833eb769a6df71ccf8903e8dc5447cfce"},
   "poolboy": {:hex, :poolboy, "1.5.2", "392b007a1693a64540cead79830443abf5762f5d30cf50bc95cb2c1aaafa006b", [:rebar3], [], "hexpm", "dad79704ce5440f3d5a3681c8590b9dc25d1a561e8f5a9c995281012860901e3"},