diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0ab4eba..4126607 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,9 +2,9 @@ name: CI
 
 on:
   push:
-    branches: [ master ]
+    branches: [ main ]
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
 
 jobs:
   check_duplicate_runs:
@@ -36,12 +36,12 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - elixir: "1.10.4"
-            otp: "22.3"
-          - elixir: "1.12.2"
-            otp: "23.3"
           - elixir: "1.13.3"
             otp: "24.3"
+          - elixir: "1.14.3"
+            otp: "24.3"
+          - elixir: "1.14.3"
+            otp: "25.2"
 
     runs-on: ubuntu-latest
 
@@ -103,7 +103,7 @@ jobs:
         MIX_ENV: test
 
     - name: Run tests
-      run: mix coveralls.github
+      run: mix coveralls.github --warnings-as-errors
       env:
         GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index eb0f732..e92dfd9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -127,4 +127,4 @@ For changes on versions 1.x look on the v1.5 branch.
 ### Backwards incompatible changes
 
 - There is no `Joken.Plug` module anymore. Depending on requests we can bring that back, but we believe it is better to be on a different library;
-- The API surface changed a lot but you can still use Joken with the same [token pattern as versions 1.x](http://trivelop.de/2018/05/14/flow-elixir-designing-apis/). Please see our [migrating guide](https://github.com/joken-elixir/joken/blob/master/guides/migration_from_1.md).
+- The API surface changed a lot but you can still use Joken with the same [token pattern as versions 1.x](http://trivelop.de/2018/05/14/flow-elixir-designing-apis/). Please see our [migrating guide](https://github.com/joken-elixir/joken/blob/main/guides/migration_from_1.md).
diff --git a/README.md b/README.md
index 850360c..d6661fc 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,11 @@
 # Joken
 
-[![Build](https://travis-ci.org/joken-elixir/joken.svg?branch=master)](https://travis-ci.org/joken-elixir/joken)
+[![Build](https://travis-ci.org/joken-elixir/joken.svg?branch=main)](https://travis-ci.org/joken-elixir/joken)
 [![Module Version](https://img.shields.io/hexpm/v/joken.svg)](https://hex.pm/packages/joken)
 [![Hex Docs](https://img.shields.io/badge/hex-docs-lightgreen.svg)](https://hexdocs.pm/joken/)
 [![Total Download](https://img.shields.io/hexpm/dt/joken.svg)](https://hex.pm/packages/joken)
-[![License](https://img.shields.io/hexpm/l/joken.svg)](https://github.com/joken-elixir/joken/blob/master/LICENSE)
-[![Last Updated](https://img.shields.io/github/last-commit/joken-elixir/joken.svg)](https://github.com/joken-elixir/joken/commits/master)
+[![License](https://img.shields.io/hexpm/l/joken.svg)](https://github.com/joken-elixir/joken/blob/main/LICENSE)
+[![Last Updated](https://img.shields.io/github/last-commit/joken-elixir/joken.svg)](https://github.com/joken-elixir/joken/commits/main)
 
 A JSON Web Token (JWT) Library.
 
diff --git a/config/config.exs b/config/config.exs
index 98f0a32..8294497 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -1,6 +1,6 @@
-use Mix.Config
+import Config
 
-case Mix.env() do
+case config_env() do
   # Use the same key config as tests for benchmarking
   :bench ->
     import_config("test.exs")
diff --git a/config/dev.exs b/config/dev.exs
index ae2f5f8..edb23dd 100644
--- a/config/dev.exs
+++ b/config/dev.exs
@@ -1,3 +1,3 @@
-use Mix.Config
+import Config
 
 config :joken, default_signer: "s3cr3t"
diff --git a/config/prod.exs b/config/prod.exs
index d2d855e..becde76 100644
--- a/config/prod.exs
+++ b/config/prod.exs
@@ -1 +1 @@
-use Mix.Config
+import Config
diff --git a/config/test.exs b/config/test.exs
index 49db52d..44169f0 100644
--- a/config/test.exs
+++ b/config/test.exs
@@ -1,6 +1,6 @@
 # This file is responsible for configuring your application
 # and its dependencies with the aid of the Mix.Config module.
-use Mix.Config
+import Config
 
 rsa_map_key = %{
   "d" =>
diff --git a/guides/asymmetric_cryptography_signers.md b/guides/asymmetric_cryptography_signers.md
index 774a606..9cf4897 100644
--- a/guides/asymmetric_cryptography_signers.md
+++ b/guides/asymmetric_cryptography_signers.md
@@ -70,7 +70,7 @@ Let's see some examples on parsing asymmetric RSA keys with Joken:
 This algorithm uses the RSASSA-PKCS1-v1_5 that uses SHA2 hash algorithms. The base for this algorithm is the RSA public key standard. So, to use this algorithm we need a pair of RSA keys. There are many ways to generate these keys in different environments and is outside the scope of this library. Here is one of these ways just for an example:
 
 ``` shell
-➜  joken git:(master) openssl genrsa -out mykey.pem 4096
+➜  joken git:(main) openssl genrsa -out mykey.pem 4096
 Generating RSA private key, 4096 bit long modulus (2 primes)
 .............++++
 ...........................................................................................................++++
diff --git a/lib/joken/signer.ex b/lib/joken/signer.ex
index 309e8df..38f3b99 100644
--- a/lib/joken/signer.ex
+++ b/lib/joken/signer.ex
@@ -75,7 +75,7 @@ defmodule Joken.Signer do
   def create(alg, secret, headers) when is_binary(secret) and alg in @hs_algorithms do
     raw_create(
       alg,
-      headers |> Map.merge(%{"alg" => alg, "typ" => "JWT"}) |> JWS.from_map(),
+      headers |> transform_headers(alg) |> JWS.from_map(),
       JWK.from_oct(secret)
     )
   end
@@ -86,7 +86,7 @@ defmodule Joken.Signer do
   def create(alg, %{"pem" => pem}, headers) when alg in @map_key_algorithms do
     raw_create(
       alg,
-      headers |> Map.merge(%{"alg" => alg, "typ" => "JWT"}) |> JWS.from_map(),
+      headers |> transform_headers(alg) |> JWS.from_map(),
       JWK.from_pem(pem)
     )
   end
@@ -94,7 +94,7 @@ defmodule Joken.Signer do
   def create(alg, key, headers) when is_map(key) and alg in @map_key_algorithms do
     raw_create(
       alg,
-      headers |> Map.merge(%{"alg" => alg, "typ" => "JWT"}) |> JWS.from_map(),
+      headers |> transform_headers(alg) |> JWS.from_map(),
       JWK.from_map(key)
     )
   end
@@ -239,17 +239,19 @@ defmodule Joken.Signer do
     {jwk_function, value} = List.first(key_config)
 
     if signer_alg in @algorithms do
-      do_parse_signer(jwk_function.(value), signer_alg, headers)
+      raw_create(
+        signer_alg,
+        headers |> transform_headers(signer_alg) |> JWS.from_map(),
+        jwk_function.(value)
+      )
     else
       raise Joken.Error, :unrecognized_algorithm
     end
   end
 
-  defp do_parse_signer(jwk, signer_alg, headers) do
-    raw_create(
-      signer_alg,
-      headers |> Map.merge(%{"alg" => signer_alg, "typ" => "JWT"}) |> JWS.from_map(),
-      jwk
-    )
+  defp transform_headers(headers, signer_alg) when is_map(headers) and is_binary(signer_alg) do
+    headers
+    |> Map.put("alg", signer_alg)
+    |> Map.put_new("typ", "JWT")
   end
 end
diff --git a/mix.exs b/mix.exs
index c8ee3d4..374dfeb 100644
--- a/mix.exs
+++ b/mix.exs
@@ -9,7 +9,7 @@ defmodule Joken.Mixfile do
       app: :joken,
       version: @version,
       name: "Joken",
-      elixir: "~> 1.10",
+      elixir: "~> 1.13",
       elixirc_paths: elixirc_paths(Mix.env()),
       start_permanent: Mix.env() == :prod,
       consolidate_protocols: Mix.env() != :test,
@@ -56,7 +56,7 @@ defmodule Joken.Mixfile do
       # Test
       {:junit_formatter, "~> 3.1", only: :test},
       {:stream_data, "~> 0.5", only: :test},
-      {:excoveralls, "~> 0.14", only: :test}
+      {:excoveralls, "~> 0.15", only: :test}
     ]
   end
 
diff --git a/mix.lock b/mix.lock
index 1189143..8dcbbd2 100644
--- a/mix.lock
+++ b/mix.lock
@@ -5,13 +5,13 @@
   "credo": {:hex, :credo, "1.6.7", "323f5734350fd23a456f2688b9430e7d517afb313fbd38671b8a4449798a7854", [:mix], [{:bunt, "~> 0.2.1", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2.8", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "41e110bfb007f7eda7f897c10bf019ceab9a0b269ce79f015d54b0dcf4fc7dd3"},
   "deep_merge": {:hex, :deep_merge, "1.0.0", "b4aa1a0d1acac393bdf38b2291af38cb1d4a52806cf7a4906f718e1feb5ee961", [:mix], [], "hexpm", "ce708e5f094b9cd4e8f2be4f00d2f4250c4095be93f8cd6d018c753894885430"},
   "dialyxir": {:hex, :dialyxir, "1.2.0", "58344b3e87c2e7095304c81a9ae65cb68b613e28340690dfe1a5597fd08dec37", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "61072136427a851674cab81762be4dbeae7679f85b1272b6d25c3a839aff8463"},
-  "earmark_parser": {:hex, :earmark_parser, "1.4.26", "f4291134583f373c7d8755566122908eb9662df4c4b63caa66a0eabe06569b0a", [:mix], [], "hexpm", "48d460899f8a0c52c5470676611c01f64f3337bad0b26ddab43648428d94aabc"},
+  "earmark_parser": {:hex, :earmark_parser, "1.4.30", "0b938aa5b9bafd455056440cdaa2a79197ca5e693830b4a982beada840513c5f", [:mix], [], "hexpm", "3b5385c2d36b0473d0b206927b841343d25adb14f95f0110062506b300cd5a1b"},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
-  "ex_doc": {:hex, :ex_doc, "0.28.5", "3e52a6d2130ce74d096859e477b97080c156d0926701c13870a4e1f752363279", [:mix], [{:earmark_parser, "~> 1.4.19", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "d2c4b07133113e9aa3e9ba27efb9088ba900e9e51caa383919676afdf09ab181"},
-  "excoveralls": {:hex, :excoveralls, "0.15.1", "83c8cf7973dd9d1d853dce37a2fb98aaf29b564bf7d01866e409abf59dac2c0e", [:mix], [{:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "f8416bd90c0082d56a2178cf46c837595a06575f70a5624f164a1ffe37de07e7"},
+  "ex_doc": {:hex, :ex_doc, "0.29.1", "b1c652fa5f92ee9cf15c75271168027f92039b3877094290a75abcaac82a9f77", [:mix], [{:earmark_parser, "~> 1.4.19", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1", [hex: :makeup_erlang, repo: "hexpm", optional: false]}], "hexpm", "b7745fa6374a36daf484e2a2012274950e084815b936b1319aeebcf7809574f6"},
+  "excoveralls": {:hex, :excoveralls, "0.15.3", "54bb54043e1cf5fe431eb3db36b25e8fd62cf3976666bafe491e3fa5e29eba47", [:mix], [{:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "f8eb5d8134d84c327685f7bb8f1db4147f1363c3c9533928234e496e3070114e"},
   "file_system": {:hex, :file_system, "0.2.10", "fb082005a9cd1711c05b5248710f8826b02d7d1784e7c3451f9c1231d4fc162d", [:mix], [], "hexpm", "41195edbfb562a593726eda3b3e8b103a309b733ad25f3d642ba49696bf715dc"},
-  "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"},
-  "idna": {:hex, :idna, "6.1.1", "8a63070e9f7d0c62eb9d9fcb360a7de382448200fbbd1b106cc96d3d8099df8d", [:rebar3], [{:unicode_util_compat, "~>0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "92376eb7894412ed19ac475e4a86f7b413c1b9fbb5bd16dccd57934157944cea"},
+  "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"},
+  "idna": {:hex, :idna, "6.1.1", "8a63070e9f7d0c62eb9d9fcb360a7de382448200fbbd1b106cc96d3d8099df8d", [:rebar3], [{:unicode_util_compat, "~> 0.7.0", [hex: :unicode_util_compat, repo: "hexpm", optional: false]}], "hexpm", "92376eb7894412ed19ac475e4a86f7b413c1b9fbb5bd16dccd57934157944cea"},
   "jason": {:hex, :jason, "1.4.0", "e855647bc964a44e2f67df589ccf49105ae039d4179db7f6271dfd3843dc27e6", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "79a3791085b2a0f743ca04cec0f7be26443738779d09302e01318f97bdb82121"},
   "jose": {:hex, :jose, "1.11.5", "3bc2d75ffa5e2c941ca93e5696b54978323191988eb8d225c2e663ddfefd515e", [:mix, :rebar3], [], "hexpm", "dcd3b215bafe02ea7c5b23dafd3eb8062a5cd8f2d904fd9caa323d37034ab384"},
   "junit_formatter": {:hex, :junit_formatter, "3.3.1", "c729befb848f1b9571f317d2fefa648e9d4869befc4b2980daca7c1edc468e40", [:mix], [], "hexpm", "761fc5be4b4c15d8ba91a6dafde0b2c2ae6db9da7b8832a55b5a1deb524da72b"},
diff --git a/test/joken_signer_test.exs b/test/joken_signer_test.exs
index a762ab2..5b856cb 100644
--- a/test/joken_signer_test.exs
+++ b/test/joken_signer_test.exs
@@ -121,6 +121,13 @@ defmodule Joken.Signer.Test do
 
   test "can parse with key_id" do
     {:ok, token, _claims} = Joken.encode_and_sign(%{}, Signer.parse_config(:with_key_id))
+
     assert {:ok, %{"kid" => "my_key_id", "alg" => "HS256"}} = Joken.peek_header(token)
   end
+
+  test "can override typ header claim" do
+    signer = Signer.create("HS256", "secret", %{"typ" => "SOMETHING_ELSE"})
+    {:ok, token, _claims} = Joken.encode_and_sign(%{}, signer)
+    assert {:ok, %{"typ" => "SOMETHING_ELSE"}} = Joken.peek_header(token)
+  end
 end
diff --git a/test/joken_test.exs b/test/joken_test.exs
index 1e3f7b1..7ab29f9 100644
--- a/test/joken_test.exs
+++ b/test/joken_test.exs
@@ -1,7 +1,7 @@
 defmodule JokenTest do
   use ExUnit.Case, async: true
   import ExUnit.CaptureLog
-  import Joken.Config, only: [add_claim: 4, add_claim: 5, default_claims: 1]
+  import Joken.Config, only: [add_claim: 4, add_claim: 5]
   alias Joken.CurrentTime.Mock
 
   setup do