diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9645744..74c9671 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,11 @@
 # Changelog
 
+## Unreleased
+
+### Enhancements
+
+- Mark `ex_keccak` as optional using SKIP_EX_KECCAK environment variable
+
 ## v0.5.0 (2024-05-29)
 
 ### Breaking Changes
diff --git a/README.md b/README.md
index d1b8de7..217378e 100644
--- a/README.md
+++ b/README.md
@@ -278,6 +278,21 @@ MyERC20Token.transfer("0x[Recipient]", 1000)
 )
 ```
 
+## Switching the ex_keccak library
+
+`ex_keccak` is a Rustler NIF that brings keccak256 hashing to elixir.
+It is the default used library in `ex_abi` and `ethers`. If for some reason you need to use a
+different library (e.g. target does not support rustler) you can use the Application config value
+and on top of that set the environment variable `SKIP_EX_KECCAK=true` so ex_keccak is marked as
+optional in hex dependencies.
+
+```elixir
+# config.exs
+config :ethers, keccak_module: MyKeccakModule
+
+# Also make sure to set SKIP_EX_KECCAK=true when fetching dependencies and building them
+```
+
 ## Contributing
 
 All contributions are very welcome (as simple as fixing typos). Please feel free to open issues and
diff --git a/mix.exs b/mix.exs
index d500ce9..1a4afac 100644
--- a/mix.exs
+++ b/mix.exs
@@ -101,8 +101,9 @@ defmodule Ethers.MixProject do
       {:credo, "~> 1.7", only: [:dev, :test], runtime: false},
       {:dialyxir, "~> 1.3", only: [:dev, :test], runtime: false},
       {:ethereumex, "~> 0.10.6"},
-      {:ex_abi, "~> 0.7.0"},
+      {:ex_abi, "~> 0.8.0", optional: System.get_env("SKIP_EX_KECCAK") == "true"},
       {:ex_doc, "~> 0.32", only: :dev, runtime: false},
+      {:ex_keccak, "~> 0.7.5"},
       {:ex_rlp, "~> 0.6.0"},
       {:ex_secp256k1, "~> 0.7.2", optional: true},
       {:excoveralls, "~> 0.10", only: :test},
diff --git a/mix.lock b/mix.lock
index 7062c35..be90789 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,12 +1,12 @@
 %{
   "bunt": {:hex, :bunt, "1.0.0", "081c2c665f086849e6d57900292b3a161727ab40431219529f13c4ddcf3e7a44", [:mix], [], "hexpm", "dc5f86aa08a5f6fa6b8096f0735c4e76d54ae5c9fa2c143e5a1fc7c1cd9bb6b5"},
-  "castore": {:hex, :castore, "1.0.6", "ffc42f110ebfdafab0ea159cd43d31365fa0af0ce4a02ecebf1707ae619ee727", [:mix], [], "hexpm", "374c6e7ca752296be3d6780a6d5b922854ffcc74123da90f2f328996b962d33a"},
+  "castore": {:hex, :castore, "1.0.8", "dedcf20ea746694647f883590b82d9e96014057aff1d44d03ec90f36a5c0dc6e", [:mix], [], "hexpm", "0b2b66d2ee742cb1d9cb8c8be3b43c3a70ee8651f37b75a8b982e036752983f1"},
   "credo": {:hex, :credo, "1.7.7", "771445037228f763f9b2afd612b6aa2fd8e28432a95dbbc60d8e03ce71ba4446", [:mix], [{:bunt, "~> 0.2.1 or ~> 1.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2 or ~> 1.0", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "8bc87496c9aaacdc3f90f01b7b0582467b69b4bd2441fe8aae3109d843cc2f2e"},
   "dialyxir": {:hex, :dialyxir, "1.4.3", "edd0124f358f0b9e95bfe53a9fcf806d615d8f838e2202a9f430d59566b6b53b", [:mix], [{:erlex, ">= 0.2.6", [hex: :erlex, repo: "hexpm", optional: false]}], "hexpm", "bf2cfb75cd5c5006bec30141b131663299c661a864ec7fbbc72dfa557487a986"},
   "earmark_parser": {:hex, :earmark_parser, "1.4.40", "f3534689f6b58f48aa3a9ac850d4f05832654fe257bf0549c08cc290035f70d5", [:mix], [], "hexpm", "cdb34f35892a45325bad21735fadb88033bcb7c4c296a999bde769783f53e46a"},
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
   "ethereumex": {:hex, :ethereumex, "0.10.6", "6d75cac39b5b7a720b064fe48563f205d3d9784e5bde25f983dd07cf306c2a6d", [:make, :mix], [{:finch, "~> 0.16", [hex: :finch, repo: "hexpm", optional: false]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "58cf926239dabf8bd1fc6cf50a37b926274240b7f58ba5b235a20b5500a9a7e1"},
-  "ex_abi": {:hex, :ex_abi, "0.7.2", "9950d8aa764c74b8c89cc279c72ac786675aca315c08bc06b4a387407fe67873", [:mix], [{:ex_keccak, "~> 0.7.5", [hex: :ex_keccak, repo: "hexpm", optional: false]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "1ca991d6eb497959aab4b3aaeb7d0f71b67d4b617d5689113da82d6e4cedc408"},
+  "ex_abi": {:hex, :ex_abi, "0.8.0", "bb08827bd8d71dbb311c69ac55a008669dfabe2ce5b58d65f97c08c0aba60ec6", [:mix], [{:ex_keccak, "~> 0.7.5", [hex: :ex_keccak, repo: "hexpm", optional: true]}, {:jason, "~> 1.4", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "bbdae12c186aeeb4c53dd7c7c57f457923602db315aa1f66d7427467c8ad77af"},
   "ex_doc": {:hex, :ex_doc, "0.34.2", "13eedf3844ccdce25cfd837b99bea9ad92c4e511233199440488d217c92571e8", [:mix], [{:earmark_parser, "~> 1.4.39", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_c, ">= 0.1.0", [hex: :makeup_c, repo: "hexpm", optional: true]}, {:makeup_elixir, "~> 0.14 or ~> 1.0", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1 or ~> 1.0", [hex: :makeup_erlang, repo: "hexpm", optional: false]}, {:makeup_html, ">= 0.1.0", [hex: :makeup_html, repo: "hexpm", optional: true]}], "hexpm", "5ce5f16b41208a50106afed3de6a2ed34f4acfd65715b82a0b84b49d995f95c1"},
   "ex_keccak": {:hex, :ex_keccak, "0.7.5", "f3b733173510d48ae9a1ea1de415e694b2651f35c787e63f33b5ed0013fbfd35", [:mix], [{:rustler, ">= 0.0.0", [hex: :rustler, repo: "hexpm", optional: true]}, {:rustler_precompiled, "~> 0.7", [hex: :rustler_precompiled, repo: "hexpm", optional: false]}], "hexpm", "8a5e1cb7f96fff5e480ff6a121477b90c4fd8c150984086dffd98819f5d83763"},
   "ex_rlp": {:hex, :ex_rlp, "0.6.0", "985391d2356a7cb8712a4a9a2deb93f19f2fbca0323f5c1203fcaf64d077e31e", [:mix], [], "hexpm", "7135db93b861d9e76821039b60b00a6a22d2c4e751bf8c444bffe7a042f1abaf"},
@@ -26,7 +26,7 @@
   "nimble_parsec": {:hex, :nimble_parsec, "1.4.0", "51f9b613ea62cfa97b25ccc2c1b4216e81df970acd8e16e8d1bdc58fef21370d", [:mix], [], "hexpm", "9c565862810fb383e9838c1dd2d7d2c437b3d13b267414ba6af33e50d2d1cf28"},
   "nimble_pool": {:hex, :nimble_pool, "1.1.0", "bf9c29fbdcba3564a8b800d1eeb5a3c58f36e1e11d7b7fb2e084a643f645f06b", [:mix], [], "hexpm", "af2e4e6b34197db81f7aad230c1118eac993acc0dae6bc83bac0126d4ae0813a"},
   "poolboy": {:hex, :poolboy, "1.5.2", "392b007a1693a64540cead79830443abf5762f5d30cf50bc95cb2c1aaafa006b", [:rebar3], [], "hexpm", "dad79704ce5440f3d5a3681c8590b9dc25d1a561e8f5a9c995281012860901e3"},
-  "rustler_precompiled": {:hex, :rustler_precompiled, "0.7.1", "ecadf02cc59a0eccbaed6c1937303a5827fbcf60010c541595e6d3747d3d0f9f", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: false]}, {:rustler, "~> 0.23", [hex: :rustler, repo: "hexpm", optional: true]}], "hexpm", "b9e4657b99a1483ea31502e1d58c464bedebe9028808eda45c3a429af4550c66"},
+  "rustler_precompiled": {:hex, :rustler_precompiled, "0.7.2", "097f657e401f02e7bc1cab808cfc6abdc1f7b9dc5e5adee46bf2fd8fdcce9ecf", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: false]}, {:rustler, "~> 0.23", [hex: :rustler, repo: "hexpm", optional: true]}], "hexpm", "7663faaeadc9e93e605164dcf9e69168e35f2f8b7f2b9eb4e400d1a8e0fe2999"},
   "telemetry": {:hex, :telemetry, "1.2.1", "68fdfe8d8f05a8428483a97d7aab2f268aaff24b49e0f599faa091f1d4e7f61c", [:rebar3], [], "hexpm", "dad9ce9d8effc621708f99eac538ef1cbe05d6a874dd741de2e689c47feafed5"},
   "unicode_util_compat": {:hex, :unicode_util_compat, "0.7.0", "bc84380c9ab48177092f43ac89e4dfa2c6d62b40b8bd132b1059ecc7232f9a78", [:rebar3], [], "hexpm", "25eee6d67df61960cf6a794239566599b09e17e668d3700247bc498638152521"},
 }