diff --git a/lib/tower/igniter.ex b/lib/tower/igniter.ex
index 0cfca6f..83e3e5c 100644
--- a/lib/tower/igniter.ex
+++ b/lib/tower/igniter.ex
@@ -1,5 +1,10 @@
 if Code.ensure_loaded?(Igniter) do
   defmodule Tower.Igniter do
+    @runtime_file_path "config/runtime.exs"
+    @default_runtime_file_content """
+    import Config
+    """
+
     def reporters_list_append(igniter, module) do
       Igniter.Project.Config.configure(
         igniter,
@@ -11,18 +16,93 @@ if Code.ensure_loaded?(Igniter) do
       )
     end
 
-    def runtime_configure_reporter(igniter, application, items) do
-      items
-      |> Enum.reduce(igniter, fn {key, value}, igniter ->
-        Igniter.Project.Config.configure(
-          igniter,
-          "runtime.exs",
-          application,
-          [key],
-          value,
-          updater: &{:ok, &1}
-        )
-      end)
+    def runtime_configure_reporter(igniter, application, items, opts \\ []) do
+      env = opts[:env]
+
+      igniter
+      |> Igniter.include_or_create_file(@runtime_file_path, @default_runtime_file_content)
+      |> Igniter.update_elixir_file(
+        @runtime_file_path,
+        fn zipper ->
+          if Igniter.Project.Config.configures_root_key?(zipper, application) do
+            {:ok, zipper}
+          else
+            if env do
+              patterns = env_config_patterns(env)
+
+              zipper
+              |> Igniter.Code.Common.move_to_cursor_match_in_scope(patterns)
+              |> case do
+                {:ok, zipper} ->
+                  {:ok, zipper}
+
+                :error ->
+                  zipper
+                  |> Igniter.Code.Common.add_code("""
+                  if config_env() == #{inspect(env)} do
+                  end
+                  """)
+                  |> Igniter.Code.Common.move_to_cursor_match_in_scope(patterns)
+              end
+            else
+              {:ok, zipper}
+            end
+            |> case do
+              {:ok, zipper} ->
+                items
+                |> Enum.map(fn {key, value} ->
+                  {
+                    key,
+                    case value do
+                      {:code, code} ->
+                        code
+
+                      other ->
+                        other
+                        |> Macro.escape()
+                        |> Sourceror.to_string()
+                        |> Sourceror.parse_string!()
+                    end
+                  }
+                end)
+                |> Enum.reduce_while(
+                  {:ok, zipper},
+                  fn {key, value}, {:ok, zipper} ->
+                    Igniter.Project.Config.modify_config_code(
+                      zipper,
+                      [key],
+                      application,
+                      value,
+                      updater: &{:ok, &1}
+                    )
+                    |> case do
+                      {:ok, _} = ok_result -> {:cont, ok_result}
+                      other_result -> {:halt, other_result}
+                    end
+                  end
+                )
+
+              :error ->
+                {:error, "Could not modify #{@runtime_file_path}"}
+            end
+          end
+        end
+      )
+    end
+
+    defp env_config_patterns(env) do
+      [
+        """
+        if config_env() == #{inspect(env)} do
+          __cursor__()
+        end
+        """,
+        """
+        if #{inspect(env)} == config_env() do
+          __cursor__()
+        end
+        """
+      ]
     end
   end
 end
diff --git a/test/tower/igniter_test.exs b/test/tower/igniter_test.exs
index 9863fdd..72446ee 100644
--- a/test/tower/igniter_test.exs
+++ b/test/tower/igniter_test.exs
@@ -92,6 +92,21 @@ defmodule TowerIgniterTest do
       )
     end
 
+    test "from scratch with env" do
+      test_project()
+      |> Tower.Igniter.runtime_configure_reporter(:reporter, [api_key: "123"], env: :prod)
+      |> assert_creates(
+        "config/runtime.exs",
+        """
+        import Config
+
+        if config_env() == :prod do
+          config :reporter, api_key: "123"
+        end
+        """
+      )
+    end
+
     test "appends to existing runtime config" do
       test_project(
         files: %{
@@ -100,46 +115,85 @@ defmodule TowerIgniterTest do
           """
         }
       )
-      |> Tower.Igniter.runtime_configure_reporter(:reporter, api_key: "123")
+      |> Tower.Igniter.runtime_configure_reporter(:reporter, [api_key: "123"], env: :prod)
       |> assert_has_patch(
         "config/runtime.exs",
         """
         |import Config
+        |
+        + |if config_env() == :prod do
+        + |  config :reporter, api_key: "123"
+        + |end
+        + |
+        """
+      )
+    end
+
+    test "writes inside existing prod block if present" do
+      test_project(
+        files: %{
+          "config/runtime.exs" => """
+          import Config
+
+          if config_env() == :prod do
+            IO.puts("hello")
+          end
+          """
+        }
+      )
+      |> Tower.Igniter.runtime_configure_reporter(:reporter, [api_key: "123"], env: :prod)
+      |> assert_has_patch(
+        "config/runtime.exs",
+        """
+        |if config_env() == :prod do
+        |  IO.puts("hello")
         + |config :reporter, api_key: "123"
+        |end
+        |
         """
       )
     end
 
-    test "does not append same config again" do
+    test "does not append same config again in existing env block" do
       test_project(
         files: %{
           "config/runtime.exs" => """
           import Config
 
-          config :reporter, api_key: "123"
+          if config_env() == :prod do
+            config :reporter, api_key: "123"
+          end
           """
         }
       )
-      |> Tower.Igniter.runtime_configure_reporter(:reporter, api_key: "123")
+      |> Tower.Igniter.runtime_configure_reporter(:reporter, [api_key: "123"], env: :prod)
       |> assert_unchanged()
     end
 
-    test "does not modify existing key value yet appends new key" do
+    test "does not modify existing key value yet appends new key in env block" do
       test_project(
         files: %{
           "config/runtime.exs" => """
           import Config
 
-          config :reporter, api_key: "123"
+          if config_env() == :prod do
+            config :reporter, api_key: "123"
+          end
           """
         }
       )
-      |> Tower.Igniter.runtime_configure_reporter(:reporter, api_key: "456", other_key: "789")
+      |> Tower.Igniter.runtime_configure_reporter(
+        :reporter,
+        [api_key: "456", other_key: "789"],
+        env: :prod
+      )
       |> assert_has_patch(
         "config/runtime.exs",
         """
-        - |config :reporter, api_key: "123"
-        + |config :reporter, api_key: "123", other_key: "789"
+        |if config_env() == :prod do
+        - |  config :reporter, api_key: "123"
+        + |  config :reporter, api_key: "123", other_key: "789"
+        |end
         """
       )
     end
@@ -158,6 +212,20 @@ defmodule TowerIgniterTest do
       |> assert_unchanged()
     end
 
+    test "does not modify existing config in top level if configured for env" do
+      test_project(
+        files: %{
+          "config/runtime.exs" => """
+          import Config
+
+          config :reporter, api_key: "123"
+          """
+        }
+      )
+      |> Tower.Igniter.runtime_configure_reporter(:reporter, [api_key: "123"], env: :prod)
+      |> assert_unchanged()
+    end
+
     test "is idempotent" do
       test_project()
       |> Tower.Igniter.runtime_configure_reporter(:reporter, api_key: "123")