diff --git a/lib/eth/utils.ex b/lib/eth/utils.ex
index d767848..4f7fb1f 100644
--- a/lib/eth/utils.ex
+++ b/lib/eth/utils.ex
@@ -65,7 +65,11 @@ defmodule ETH.Utils do
     [signature: signature, recovery: recovery]
   end
 
-  def keccak256(data), do: :keccakf1600.hash(:sha3_256, data)
+  def keccak256(data) do
+    {:ok, result} = ExKeccak.hash_256(data)
+    result
+  end
+
   def encode16(value), do: Base.encode16(value, case: :lower)
   def decode16(value), do: Base.decode16!(value, case: :mixed)
 
diff --git a/mix.exs b/mix.exs
index 01e3c61..a772db3 100644
--- a/mix.exs
+++ b/mix.exs
@@ -32,7 +32,7 @@ defmodule Eth.Mixfile do
       {:ex_doc, ">= 0.0.0", only: :dev},
       {:dialyxir, "~> 1.0.0", only: [:dev], runtime: false},
       {:hexate, "~> 0.6.1"},
-      {:keccakf1600, "~> 2.0", hex: :keccakf1600_orig},
+      {:ex_keccak, "~> 0.1.2"},
       {:mnemonic, "~> 0.2.1"},
       {:poison, "~> 4.0.1"},
       {:libsecp256k1, "~> 0.1.10"},
diff --git a/mix.lock b/mix.lock
index 0e436dc..5d5c631 100644
--- a/mix.lock
+++ b/mix.lock
@@ -6,6 +6,7 @@
   "erlex": {:hex, :erlex, "0.2.6", "c7987d15e899c7a2f34f5420d2a2ea0d659682c06ac607572df55a43753aa12e", [:mix], [], "hexpm", "2ed2e25711feb44d52b17d2780eabf998452f6efda104877a3881c2f8c0c0c75"},
   "ethereumex": {:hex, :ethereumex, "0.6.1", "d4497a2f66cb2deba582652e93135daec28426b195f92883b37086e56bdea9a5", [:mix], [{:httpoison, "~> 1.6", [hex: :httpoison, repo: "hexpm", optional: false]}, {:jason, "~> 1.2", [hex: :jason, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5.1", [hex: :poolboy, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4", [hex: :telemetry, repo: "hexpm", optional: true]}], "hexpm", "79be0659a8978eb0ae5184ade13878f1f1133fb402ce5ac697bf2afa08bba7e7"},
   "ex_doc": {:hex, :ex_doc, "0.23.0", "a069bc9b0bf8efe323ecde8c0d62afc13d308b1fa3d228b65bca5cf8703a529d", [:mix], [{:earmark_parser, "~> 1.4.0", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.14", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm", "f5e2c4702468b2fd11b10d39416ddadd2fcdd173ba2a0285ebd92c39827a5a16"},
+  "ex_keccak": {:hex, :ex_keccak, "0.1.2", "4548914dc250a919712f03b4574fd2d048cd6d1245481b559abe9e7b9adafbd3", [:mix], [{:rustler, "~> 0.21.1", [hex: :rustler, repo: "hexpm", optional: false]}], "hexpm", "da2a11b1f95727193865f9184b6af9e1665e82b84f3c531ab4b7323532dafebd"},
   "ex_rlp": {:hex, :ex_rlp, "0.5.3", "9055bddade545ee3e734aaad62c4b4d08211834da3beb43ae269b75785909e5e", [:mix], [], "hexpm", "a755a5f8f9f66079f3ecbe021536b949077fac0df963d9e59a20321bab28722d"},
   "hackney": {:hex, :hackney, "1.15.2", "07e33c794f8f8964ee86cebec1a8ed88db5070e52e904b8f12209773c1036085", [:rebar3], [{:certifi, "2.5.1", [hex: :certifi, repo: "hexpm", optional: false]}, {:idna, "6.0.0", [hex: :idna, repo: "hexpm", optional: false]}, {:metrics, "1.0.1", [hex: :metrics, repo: "hexpm", optional: false]}, {:mimerl, "~>1.1", [hex: :mimerl, repo: "hexpm", optional: false]}, {:ssl_verify_fun, "1.1.5", [hex: :ssl_verify_fun, repo: "hexpm", optional: false]}], "hexpm", "e0100f8ef7d1124222c11ad362c857d3df7cb5f4204054f9f0f4a728666591fc"},
   "hexate": {:hex, :hexate, "0.6.1", "1cea42e462c1daa32223127d4752e71016c3d933d492b9bb7fa4709a4a0fd50d", [:mix], [], "hexpm", "667c429c0970e3097107c9fafcc645636302888388845d78a3947a739fd946b7"},
@@ -24,7 +25,9 @@
   "parse_trans": {:hex, :parse_trans, "3.3.0", "09765507a3c7590a784615cfd421d101aec25098d50b89d7aa1d66646bc571c1", [:rebar3], [], "hexpm", "17ef63abde837ad30680ea7f857dd9e7ced9476cdd7b0394432af4bfc241b960"},
   "poison": {:hex, :poison, "4.0.1", "bcb755a16fac91cad79bfe9fc3585bb07b9331e50cfe3420a24bcc2d735709ae", [:mix], [], "hexpm", "ba8836feea4b394bb718a161fc59a288fe0109b5006d6bdf97b6badfcf6f0f25"},
   "poolboy": {:hex, :poolboy, "1.5.2", "392b007a1693a64540cead79830443abf5762f5d30cf50bc95cb2c1aaafa006b", [:rebar3], [], "hexpm", "dad79704ce5440f3d5a3681c8590b9dc25d1a561e8f5a9c995281012860901e3"},
+  "rustler": {:hex, :rustler, "0.21.1", "5299980be32da997c54382e945bacaa015ed97a60745e1e639beaf6a7b278c65", [:mix], [{:toml, "~> 0.5.2", [hex: :toml, repo: "hexpm", optional: false]}], "hexpm", "6ee1651e10645b2b2f3bb70502bf180341aa058709177e9bc28c105934094bc6"},
   "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.5", "6eaf7ad16cb568bb01753dbbd7a95ff8b91c7979482b95f38443fe2c8852a79b", [:make, :mix, :rebar3], [], "hexpm", "13104d7897e38ed7f044c4de953a6c28597d1c952075eb2e328bc6d6f2bfc496"},
   "telemetry": {:hex, :telemetry, "0.4.2", "2808c992455e08d6177322f14d3bdb6b625fbcfd233a73505870d8738a2f4599", [:rebar3], [], "hexpm", "2d1419bd9dda6a206d7b5852179511722e2b18812310d304620c7bd92a13fcef"},
+  "toml": {:hex, :toml, "0.5.2", "e471388a8726d1ce51a6b32f864b8228a1eb8edc907a0edf2bb50eab9321b526", [:mix], [], "hexpm", "f1e3dabef71fb510d015fad18c0e05e7c57281001141504c6b69d94e99750a07"},
   "unicode_util_compat": {:hex, :unicode_util_compat, "0.4.1", "d869e4c68901dd9531385bb0c8c40444ebf624e60b6962d95952775cac5e90cd", [:rebar3], [], "hexpm", "1d1848c40487cdb0b30e8ed975e34e025860c02e419cb615d255849f3427439d"},
 }