diff --git a/lib/perseus/auth.ex b/lib/perseus/auth.ex
index 55a9b85..75de505 100644
--- a/lib/perseus/auth.ex
+++ b/lib/perseus/auth.ex
@@ -9,12 +9,17 @@ defmodule Perseus.Auth do
   @signup_token_ttl 60 * 15
   @session_token_ttl 60 * 60
 
-  def send_login_email(email, url_fun) do
+  def send_login_email(email, url_fun \\ nil) do
     with {:ok, _} <- Accounts.get_user_by_email(email),
          {:ok, token} <- generate_login_token(email),
-         encoded_token <- BinaryUtils.encode(token),
-         {:ok, _} <- UserNotifier.deliver_login_link(email, url_fun.(encoded_token)) do
-      :ok
+         encoded_token <- BinaryUtils.encode(token) do
+      # If `url_fun` is provided, deliver the login link via email
+      if url_fun do
+        UserNotifier.deliver_login_link(email, url_fun.(encoded_token))
+      else
+        # Otherwise, just return the encoded token
+        {:ok, encoded_token}
+      end
     else
       _ -> :error
     end
diff --git a/test/perseus/auth/token_store_test.exs b/test/perseus/auth/token_store_test.exs
index cd9d584..ca0f0cb 100644
--- a/test/perseus/auth/token_store_test.exs
+++ b/test/perseus/auth/token_store_test.exs
@@ -13,6 +13,7 @@ defmodule Perseus.Auth.TokenStoreTest do
   setup do
     # Create an ETS table for testing purposes
     init_table(@magic_link_table)
+    init_table(@signup_table)
     init_table(@session_table)
     :ok
   end
@@ -56,9 +57,9 @@ defmodule Perseus.Auth.TokenStoreTest do
     end
 
     test "stores session token correctly", %{token: token, user: user, ttl: ttl} do
-      TokenStore.store_signup_token(token, user, ttl)
+      TokenStore.store_session_token(token, user, ttl)
 
-      assert [{^token, ^user, _}] = :ets.lookup(@signup_table, token)
+      assert [{^token, ^user, _}] = :ets.lookup(@session_table, token)
     end
   end
 
diff --git a/test/perseus_web/resolvers/auth_test.exs b/test/perseus_web/resolvers/auth_test.exs
new file mode 100644
index 0000000..3984ee7
--- /dev/null
+++ b/test/perseus_web/resolvers/auth_test.exs
@@ -0,0 +1,55 @@
+defmodule PerseusWeb.Resolvers.AuthTest do
+  use Perseus.DataCase
+
+  alias Perseus.Auth
+  alias PerseusWeb.Resolvers
+
+  import Perseus.AccountsFixtures
+
+  describe "login_user/3" do
+    setup do
+      %{user: user_fixture()}
+    end
+
+    test "with valid context should login user", %{user: user} do
+      result = Resolvers.Auth.login_user(nil, nil, %{context: %{email: user.email}})
+
+      # Assert that the resolver returns :ok and a session_token
+      assert {:ok, %{session_token: session_token}} = result
+      assert {:ok, ^user} = Auth.find_user(session_token)
+    end
+
+    test "with invalid email address should return error" do
+      result = Resolvers.Auth.login_user(nil, nil, %{context: %{email: "invalid@example.com"}})
+
+      # Assert that the resolver returns :ok and a session_token
+      assert {:error, "User not found"} = result
+    end
+  end
+
+  describe "signup_user/3" do
+    setup do
+      %{user: valid_user_attributes()}
+    end
+
+    test "with valid data should signup user", %{user: user} do
+      result = Resolvers.Auth.signup_user(nil, %{user: user}, %{context: %{email: user.email}})
+
+      assert {:ok, %{session: _, new_user: created_user}} = result
+      assert created_user.email == user.email
+      assert created_user.first_name == user.first_name
+      assert created_user.last_name == user.last_name
+      assert created_user.verified == false
+    end
+
+    test "with invalid data should return a changeset" do
+      result =
+        Resolvers.Auth.signup_user(nil, %{user: %{first_name: "test"}}, %{
+          context: %{email: "invalid"}
+        })
+
+      assert {:error, %Ecto.Changeset{} = changeset} = result
+      assert "can't be blank" in errors_on(changeset).last_name
+    end
+  end
+end
diff --git a/test/perseus_web/schema/mutations/auth_mutations_test.exs b/test/perseus_web/schema/mutations/auth_mutations_test.exs
new file mode 100644
index 0000000..908d193
--- /dev/null
+++ b/test/perseus_web/schema/mutations/auth_mutations_test.exs
@@ -0,0 +1,44 @@
+defmodule PerseusWeb.Schema.Mutations.AuthMutationsTest do
+  alias Perseus.Utils.BinaryUtils
+  alias Perseus.Auth
+  use PerseusWeb.ConnCase, async: true
+
+  import Perseus.AccountsFixtures
+
+  # Define the query that you will be testing
+  @login_query """
+  mutation startSession {
+    logIn {
+      sessionToken
+    }
+  }
+  """
+
+  describe "login mutation" do
+    setup do
+      user = user_fixture()
+      {:ok, token} = Auth.send_login_email(user.email)
+      %{user: user, token: token}
+    end
+
+    test "should login when email is found", %{conn: conn, user: user, token: token} do
+      conn =
+        conn
+        |> put_req_header("authorization", "MagicLink " <> token)
+        |> put_req_header("x-custom-header", "custom-value")
+        |> post("/api/graphql", %{query: @login_query})
+
+      assert json_response(conn, 200)
+      response_data = json_response(conn, 200)["data"]
+
+      assert %{
+               "logIn" => %{
+                 "sessionToken" => session_token
+               }
+             } = response_data
+
+      {:ok, decoded_session_token} = BinaryUtils.decode(session_token)
+      assert {:ok, ^user} = Auth.find_user(decoded_session_token)
+    end
+  end
+end
diff --git a/test/support/fixtures/accounts_fixtures.ex b/test/support/fixtures/accounts_fixtures.ex
index 5055b63..e99825a 100644
--- a/test/support/fixtures/accounts_fixtures.ex
+++ b/test/support/fixtures/accounts_fixtures.ex
@@ -10,14 +10,18 @@ defmodule Perseus.AccountsFixtures do
   def user_fixture(attrs \\ %{}) do
     {:ok, user} =
       attrs
-      |> Enum.into(%{
-        email: "someemail@example.com",
-        first_name: "some first_name",
-        last_name: "some last_name",
-        verified: true
-      })
+      |> valid_user_attributes()
       |> Perseus.Accounts.create_user()
 
     user
   end
+
+  def valid_user_attributes(attr \\ %{}) do
+    Enum.into(attr, %{
+      email: "someemail@example.com",
+      first_name: "some first_name",
+      last_name: "some last_name",
+      verified: true
+    })
+  end
 end