diff --git a/lib/sigaws/crypto/hmac.ex b/lib/sigaws/crypto/hmac.ex
index 95fb792..e4a2f3c 100644
--- a/lib/sigaws/crypto/hmac.ex
+++ b/lib/sigaws/crypto/hmac.ex
@@ -1,6 +1,13 @@
 defmodule Sigaws.Crypto.HMAC do
   @moduledoc false
-  def init(type, key), do: :crypto.hmac_init(type, key)
-  def update(hmac_ctxt, data), do: :crypto.hmac_update(hmac_ctxt, data)
-  def compute(hmac_ctxt), do: :crypto.hmac_final(hmac_ctxt)
+
+  if System.otp_release() |> String.to_integer() < 24 do
+    def init(type, key), do: :crypto.hmac_init(type, key)
+    def update(hmac_ctxt, data), do: :crypto.hmac_update(hmac_ctxt, data)
+    def compute(hmac_ctxt), do: :crypto.hmac_final(hmac_ctxt)
+  else
+    def init(type, key), do: :crypto.mac_init(:hmac, type, key)
+    def update(hmac_ctxt, data), do: :crypto.mac_update(hmac_ctxt, data)
+    def compute(hmac_ctxt), do: :crypto.mac_final(hmac_ctxt)
+  end
 end
diff --git a/mix.exs b/mix.exs
index 60dfc9d..b040c77 100644
--- a/mix.exs
+++ b/mix.exs
@@ -28,7 +28,7 @@ defmodule Sigaws.Mixfile do
   # Type "mix help compile.app" for more information
   def application do
     # Specify extra applications you'll use from Erlang/Elixir
-    [extra_applications: [:logger]]
+    [extra_applications: [:crypto, :logger]]
   end
 
   # Type "mix help deps" for more examples and options
diff --git a/mix.lock b/mix.lock
index 0fb95f9..c67f678 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,15 +1,17 @@
-%{"certifi": {:hex, :certifi, "2.0.0", "a0c0e475107135f76b8c1d5bc7efb33cd3815cb3cf3dea7aefdd174dabead064", [:rebar3], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.2.3", "206eb2e2ac1a794aa5256f3982de7a76bf4579ff91cb28d0e17ea2c9491e46a4", [:mix], [], "hexpm"},
-  "ex_doc": {:hex, :ex_doc, "0.18.1", "37c69d2ef62f24928c1f4fdc7c724ea04aecfdf500c4329185f8e3649c915baf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"},
-  "excoveralls": {:hex, :excoveralls, "0.7.4", "3d84b2f15a0e593159f74b19f83794b464b34817183d27965bdc6c462de014f9", [:mix], [{:exjsx, ">= 3.0.0", [hex: :exjsx, repo: "hexpm", optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm"},
-  "exjsx": {:hex, :exjsx, "4.0.0", "60548841e0212df401e38e63c0078ec57b33e7ea49b032c796ccad8cde794b5c", [:mix], [{:jsx, "~> 2.8.0", [hex: :jsx, repo: "hexpm", optional: false]}], "hexpm"},
-  "fsm": {:hex, :fsm, "0.3.0", "d00e0a3c68f8cf8feb24ce3a732164638ec652c48ce416b66d4e375b6ee415eb", [:mix], [], "hexpm"},
-  "hackney": {:hex, :hackney, "1.10.1", "c38d0ca52ea80254936a32c45bb7eb414e7a96a521b4ce76d00a69753b157f21", [:rebar3], [{:certifi, "2.0.0", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "5.1.0", [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, "1.1.1", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}], "hexpm"},
-  "idna": {:hex, :idna, "5.1.0", "d72b4effeb324ad5da3cab1767cb16b17939004e789d8c0ad5b70f3cea20c89a", [:rebar3], [{:unicode_util_compat, "0.3.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm"},
-  "inch_ex": {:hex, :inch_ex, "0.5.6", "418357418a553baa6d04eccd1b44171936817db61f4c0840112b420b8e378e67", [:mix], [{:poison, "~> 1.5 or ~> 2.0 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: false]}], "hexpm"},
-  "jsx": {:hex, :jsx, "2.8.3", "a05252d381885240744d955fbe3cf810504eb2567164824e19303ea59eef62cf", [:mix, :rebar3], [], "hexpm"},
-  "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm"},
-  "mimerl": {:hex, :mimerl, "1.0.2", "993f9b0e084083405ed8252b99460c4f0563e41729ab42d9074fd5e52439be88", [:rebar3], [], "hexpm"},
-  "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm"},
-  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.1", "28a4d65b7f59893bc2c7de786dec1e1555bd742d336043fe644ae956c3497fbe", [:make, :rebar], [], "hexpm"},
-  "unicode_util_compat": {:hex, :unicode_util_compat, "0.3.1", "a1f612a7b512638634a603c8f401892afbf99b8ce93a45041f8aaca99cadb85e", [:rebar3], [], "hexpm"}}
+%{
+  "certifi": {:hex, :certifi, "2.0.0", "a0c0e475107135f76b8c1d5bc7efb33cd3815cb3cf3dea7aefdd174dabead064", [:rebar3], [], "hexpm", "fdc6066ceeccb3aa14049ab6edf0b9af3b64ae1b0db2a92d5c52146f373bbb1c"},
+  "earmark": {:hex, :earmark, "1.2.3", "206eb2e2ac1a794aa5256f3982de7a76bf4579ff91cb28d0e17ea2c9491e46a4", [:mix], [], "hexpm", "3b1dcad3067985dd8618c38399a8ee9c4e652d52a17a4aae7a6d6fc4fcc24856"},
+  "ex_doc": {:hex, :ex_doc, "0.18.1", "37c69d2ef62f24928c1f4fdc7c724ea04aecfdf500c4329185f8e3649c915baf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm", "f050061c87ad39478c942995b5a20c40f2c0bc06525404613b8b0474cb8bd796"},
+  "excoveralls": {:hex, :excoveralls, "0.7.4", "3d84b2f15a0e593159f74b19f83794b464b34817183d27965bdc6c462de014f9", [:mix], [{:exjsx, ">= 3.0.0", [hex: :exjsx, repo: "hexpm", optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, repo: "hexpm", optional: false]}], "hexpm", "19b4b21e609c87cd28d0e2e58b85a7322accaa93cf341aa9898231303916da61"},
+  "exjsx": {:hex, :exjsx, "4.0.0", "60548841e0212df401e38e63c0078ec57b33e7ea49b032c796ccad8cde794b5c", [:mix], [{:jsx, "~> 2.8.0", [hex: :jsx, repo: "hexpm", optional: false]}], "hexpm", "32e95820a97cffea67830e91514a2ad53b888850442d6d395f53a1ac60c82e07"},
+  "fsm": {:hex, :fsm, "0.3.0", "d00e0a3c68f8cf8feb24ce3a732164638ec652c48ce416b66d4e375b6ee415eb", [:mix], [], "hexpm", "92119fd7695c2b9778db12903db2c828658747beae7331206dc03ebb7d8b5af3"},
+  "hackney": {:hex, :hackney, "1.10.1", "c38d0ca52ea80254936a32c45bb7eb414e7a96a521b4ce76d00a69753b157f21", [:rebar3], [{:certifi, "2.0.0", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "5.1.0", [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, "1.1.1", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}], "hexpm", "6b1980a33628824ec829239b6f9bfc455f60eebc19d3096a215f5f6170d675cf"},
+  "idna": {:hex, :idna, "5.1.0", "d72b4effeb324ad5da3cab1767cb16b17939004e789d8c0ad5b70f3cea20c89a", [:rebar3], [{:unicode_util_compat, "0.3.1", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "fc1a2f7340c422650504b1662f28fdf381f34cbd30664e8491744e52c9511d40"},
+  "inch_ex": {:hex, :inch_ex, "0.5.6", "418357418a553baa6d04eccd1b44171936817db61f4c0840112b420b8e378e67", [:mix], [{:poison, "~> 1.5 or ~> 2.0 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: false]}], "hexpm", "7123ca0450686a61416a06cd38e26af18fd0f8c1cff5214770a957c6e0724338"},
+  "jsx": {:hex, :jsx, "2.8.3", "a05252d381885240744d955fbe3cf810504eb2567164824e19303ea59eef62cf", [:mix, :rebar3], [], "hexpm", "fc3499fed7a726995aa659143a248534adc754ebd16ccd437cd93b649a95091f"},
+  "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm", "69b09adddc4f74a40716ae54d140f93beb0fb8978d8636eaded0c31b6f099f16"},
+  "mimerl": {:hex, :mimerl, "1.0.2", "993f9b0e084083405ed8252b99460c4f0563e41729ab42d9074fd5e52439be88", [:rebar3], [], "hexpm", "7a4c8e1115a2732a67d7624e28cf6c9f30c66711a9e92928e745c255887ba465"},
+  "poison": {:hex, :poison, "3.1.0", "d9eb636610e096f86f25d9a46f35a9facac35609a7591b3be3326e99a0484665", [:mix], [], "hexpm", "fec8660eb7733ee4117b85f55799fd3833eb769a6df71ccf8903e8dc5447cfce"},
+  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.1", "28a4d65b7f59893bc2c7de786dec1e1555bd742d336043fe644ae956c3497fbe", [:make, :rebar], [], "hexpm", "4f8805eb5c8a939cf2359367cb651a3180b27dfb48444846be2613d79355d65e"},
+  "unicode_util_compat": {:hex, :unicode_util_compat, "0.3.1", "a1f612a7b512638634a603c8f401892afbf99b8ce93a45041f8aaca99cadb85e", [:rebar3], [], "hexpm", "da1d9bef8a092cc7e1e51f1298037a5ddfb0f657fe862dfe7ba4c5807b551c29"},
+}