diff --git a/.travis.yml b/.travis.yml
index 80093a8..7b90169 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -11,6 +11,9 @@ addons:
 env:
   - MIX_ENV=test
 
+before_script:
+  - mix compile --warnings-as-errors
+
 script:
   - mix format --check-formatted
   - mix safe_coveralls.travis
diff --git a/lib/elixir_bench/benchmarks/benchmarks.ex b/lib/elixir_bench/benchmarks/benchmarks.ex
index c25e779..0bf4e5d 100644
--- a/lib/elixir_bench/benchmarks/benchmarks.ex
+++ b/lib/elixir_bench/benchmarks/benchmarks.ex
@@ -76,7 +76,7 @@ defmodule ElixirBench.Benchmarks do
     end
   end
 
-  def claim_job(%Runner{id: id} = runner) when is_nil(id), do: {:error, :not_found}
+  def claim_job(%Runner{id: id}) when is_nil(id), do: {:error, :not_found}
 
   def claim_job(%Runner{} = runner) do
     Repo.transaction(fn ->
diff --git a/lib/elixir_bench/repos/repos.ex b/lib/elixir_bench/repos/repos.ex
index f54c6a1..dd75257 100644
--- a/lib/elixir_bench/repos/repos.ex
+++ b/lib/elixir_bench/repos/repos.ex
@@ -48,7 +48,7 @@ defmodule ElixirBench.Repos do
     Repo.delete(repo)
   end
 
-  defp parse_slug(slug, callback) when is_nil(slug), do: {:error, :invalid_slug}
+  defp parse_slug(slug, _callback) when is_nil(slug), do: {:error, :invalid_slug}
 
   defp parse_slug(slug, callback) do
     case String.split(slug, "/", trim: true, parts: 2) do