diff --git a/config/config.exs b/config/config.exs
index e6c6cae..9b032f5 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -1,4 +1,4 @@
-use Mix.Config
+import Config
 
 # Configure git hooks
 if Mix.env() != :prod do
diff --git a/mix.exs b/mix.exs
index dc0feaa..9338d59 100644
--- a/mix.exs
+++ b/mix.exs
@@ -27,6 +27,7 @@ defmodule Varint.Mixfile do
 
   defp deps do
     [
+      {:castore, "~> 1.0"},
       {:credo, "~> 1.5", only: [:test, :dev], runtime: false},
       {:dialyxir, "~> 1.0", only: [:dev, :test], runtime: false},
       {:ex_doc, "~> 0.21", only: :dev, runtime: false},
diff --git a/mix.lock b/mix.lock
index 89596b0..c64480e 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,26 +1,19 @@
 %{
   "blankable": {:hex, :blankable, "1.0.0", "89ab564a63c55af117e115144e3b3b57eb53ad43ba0f15553357eb283e0ed425", [:mix], [], "hexpm", "7cf11aac0e44f4eedbee0c15c1d37d94c090cb72a8d9fddf9f7aec30f9278899"},
   "bunt": {:hex, :bunt, "0.2.1", "e2d4792f7bc0ced7583ab54922808919518d0e57ee162901a16a1b6664ef3b14", [:mix], [], "hexpm", "a330bfb4245239787b15005e66ae6845c9cd524a288f0d141c148b02603777a5"},
-  "certifi": {:hex, :certifi, "2.9.0", "6f2a475689dd47f19fb74334859d460a2dc4e3252a3324bd2111b8f0429e7e21", [:rebar3], [], "hexpm", "266da46bdb06d6c6d35fde799bcb28d36d985d424ad7c08b5bb48f5b5cdd4641"},
+  "castore": {:hex, :castore, "1.0.3", "7130ba6d24c8424014194676d608cb989f62ef8039efd50ff4b3f33286d06db8", [:mix], [], "hexpm", "680ab01ef5d15b161ed6a95449fac5c6b8f60055677a8e79acf01b27baa4390b"},
   "credo": {:hex, :credo, "1.7.0", "6119bee47272e85995598ee04f2ebbed3e947678dee048d10b5feca139435f75", [: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", "6839fcf63d1f0d1c0f450abc8564a57c43d644077ab96f2934563e68b8a769d7"},
   "dialyxir": {:hex, :dialyxir, "1.3.0", "fd1672f0922b7648ff9ce7b1b26fcf0ef56dda964a459892ad15f6b4410b5284", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "00b2a4bcd6aa8db9dcb0b38c1225b7277dca9bc370b6438715667071a304696f"},
   "earmark_parser": {:hex, :earmark_parser, "1.4.33", "3c3fd9673bb5dcc9edc28dd90f50c87ce506d1f71b70e3de69aa8154bc695d44", [:mix], [], "hexpm", "2d526833729b59b9fdb85785078697c72ac5e5066350663e5be6a1182da61b8f"},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
   "ex_doc": {:hex, :ex_doc, "0.30.4", "e8395c8e3c007321abb30a334f9f7c0858d80949af298302daf77553468c0c39", [:mix], [{:earmark_parser, "~> 1.4.31", [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", "9a19f0c50ffaa02435668f5242f2b2a61d46b541ebf326884505dfd3dd7af5e4"},
-  "excoveralls": {:hex, :excoveralls, "0.16.1", "0bd42ed05c7d2f4d180331a20113ec537be509da31fed5c8f7047ce59ee5a7c5", [:mix], [{:hackney, "~> 1.16", [hex: :hackney, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "dae763468e2008cf7075a64cb1249c97cb4bc71e236c5c2b5e5cdf1cfa2bf138"},
+  "excoveralls": {:hex, :excoveralls, "0.17.0", "279f124dba347903bb654bc40745c493ae265d45040001b4899ea1edf88078c7", [:mix], [{:castore, "~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "08b638d114387a888f9cb8d65f2a0021ec04c3e447b793efa7c1e734aba93004"},
   "file_system": {:hex, :file_system, "0.2.10", "fb082005a9cd1711c05b5248710f8826b02d7d1784e7c3451f9c1231d4fc162d", [:mix], [], "hexpm", "41195edbfb562a593726eda3b3e8b103a309b733ad25f3d642ba49696bf715dc"},
   "git_hooks": {:hex, :git_hooks, "0.7.3", "09489e94d88dfc767662e22aff2b6208bd7cf555a19dd0e1477cca4683ce0701", [:mix], [{:blankable, "~> 1.0.0", [hex: :blankable, repo: "hexpm", optional: false]}, {:recase, "~> 0.7.0", [hex: :recase, repo: "hexpm", optional: false]}], "hexpm", "d6ddedeb4d3a8602bc3f84e087a38f6150a86d9e790628ed8bc70e6d90681659"},
-  "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"},
+  "jason": {:hex, :jason, "1.4.1", "af1504e35f629ddcdd6addb3513c3853991f694921b1b9368b0bd32beb9f1b63", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "fbb01ecdfd565b56261302f7e1fcc27c4fb8f32d56eab74db621fc154604a7a1"},
   "makeup": {:hex, :makeup, "1.1.0", "6b67c8bc2882a6b6a445859952a602afc1a41c2e08379ca057c0f525366fc3ca", [:mix], [{:nimble_parsec, "~> 1.2.2 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "0a45ed501f4a8897f580eabf99a2e5234ea3e75a4373c8a52824f6e873be57a6"},
   "makeup_elixir": {:hex, :makeup_elixir, "0.16.1", "cc9e3ca312f1cfeccc572b37a09980287e243648108384b97ff2b76e505c3555", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.2.3 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "e127a341ad1b209bd80f7bd1620a15693a9908ed780c3b763bccf7d200c767c6"},
   "makeup_erlang": {:hex, :makeup_erlang, "0.1.2", "ad87296a092a46e03b7e9b0be7631ddcf64c790fa68a9ef5323b6cbb36affc72", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "f3f5a1ca93ce6e092d92b6d9c049bcda58a3b617a8d888f8e7231c85630e8108"},
-  "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], [], "hexpm", "69b09adddc4f74a40716ae54d140f93beb0fb8978d8636eaded0c31b6f099f16"},
-  "mimerl": {:hex, :mimerl, "1.2.0", "67e2d3f571088d5cfd3e550c383094b47159f3eee8ffa08e64106cdf5e981be3", [:rebar3], [], "hexpm", "f278585650aa581986264638ebf698f8bb19df297f66ad91b18910dfc6e19323"},
   "nimble_parsec": {:hex, :nimble_parsec, "1.3.1", "2c54013ecf170e249e9291ed0a62e5832f70a476c61da16f6aac6dca0189f2af", [:mix], [], "hexpm", "2682e3c0b2eb58d90c6375fc0cc30bc7be06f365bf72608804fb9cffa5e1b167"},
-  "parse_trans": {:hex, :parse_trans, "3.3.1", "16328ab840cc09919bd10dab29e431da3af9e9e7e7e6f0089dd5a2d2820011d8", [:rebar3], [], "hexpm", "07cd9577885f56362d414e8c4c4e6bdf10d43a8767abb92d24cbe8b24c54888b"},
   "recase": {:hex, :recase, "0.7.0", "3f2f719f0886c7a3b7fe469058ec539cb7bbe0023604ae3bce920e186305e5ae", [:mix], [], "hexpm", "36f5756a9f552f4a94b54a695870e32f4e72d5fad9c25e61bc4a3151c08a4e0c"},
-  "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.6", "cf344f5692c82d2cd7554f5ec8fd961548d4fd09e7d22f5b62482e5aeaebd4b0", [:make, :mix, :rebar3], [], "hexpm", "bdb0d2471f453c88ff3908e7686f86f9be327d065cc1ec16fa4540197ea04680"},
-  "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.0", "bc84380c9ab48177092f43ac89e4dfa2c6d62b40b8bd132b1059ecc7232f9a78", [:rebar3], [], "hexpm", "25eee6d67df61960cf6a794239566599b09e17e668d3700247bc498638152521"},
 }