diff --git a/lib/fledex/component/dot.ex b/lib/fledex/component/dot.ex
index b116eec..4db535f 100644
--- a/lib/fledex/component/dot.ex
+++ b/lib/fledex/component/dot.ex
@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: Apache-2.0
 defmodule Fledex.Component.Dot do
   @behaviour Fledex.Component.Interface
+  import Fledex.Utils.Guards
 
   @impl true
   def configure(name, options) when is_atom(name) and is_list(options) do
@@ -16,10 +17,7 @@ defmodule Fledex.Component.Dot do
       triggers when is_map(triggers) and is_map_key(triggers, trigger_name) ->
         trigger = triggers[trigger_name]
         case trigger do
-          trigger when is_integer(trigger) and (
-            (zero_indexed and trigger + 1 > 0 and trigger + 1 <= count) or
-            (not zero_indexed and trigger > 0 and trigger <= count)
-          ) ->
+          trigger when is_in_range(trigger, zero_indexed, 0, count) ->
             leds(count) |> light(color, trigger + correct_index(zero_indexed))
           _triggers ->
             leds()
diff --git a/lib/fledex/led_strip.ex b/lib/fledex/led_strip.ex
index 0a22156..5abd4af 100644
--- a/lib/fledex/led_strip.ex
+++ b/lib/fledex/led_strip.ex
@@ -92,14 +92,14 @@ defmodule Fledex.LedStrip do
   end
 
   def start_link(strip_name, drivers, global_config) do
-    raise "Unexpected arguments #{inspect(strip_name)}, #{inspect(drivers)}, #{inspect(global_config)}"
+    {:error, "Unexpected arguments #{inspect(strip_name)}, #{inspect(drivers)}, #{inspect(global_config)}"}
   end
 
   @doc """
   Define a new namespace
   """
   @spec define_namespace(atom, atom) :: :ok | {:error, String.t()}
-  def define_namespace(strip_name \\ __MODULE__, namespace) do
+  def define_namespace(strip_name, namespace) do
     # Logger.info("defining namespace: #{strip_name}-#{namespace}")
     GenServer.call(strip_name, {:define_namespace, namespace})
   end
@@ -108,7 +108,7 @@ defmodule Fledex.LedStrip do
   Drop a previously defined namespace.
   """
   @spec drop_namespace(atom, atom) :: :ok
-  def drop_namespace(strip_name \\ __MODULE__, namespace) do
+  def drop_namespace(strip_name, namespace) do
     # Logger.info("dropping namespace: #{strip_name}-#{namespace}")
     GenServer.call(strip_name, {:drop_namespace, namespace})
   end
@@ -117,7 +117,7 @@ defmodule Fledex.LedStrip do
   Checks whether the specified namespace already exists
   """
   @spec exist_namespace(atom, atom) :: boolean
-  def exist_namespace(strip_name \\ __MODULE__, namespace) do
+  def exist_namespace(strip_name, namespace) do
     GenServer.call(strip_name, {:exist_namespace, namespace})
   end
 
@@ -130,7 +130,7 @@ defmodule Fledex.LedStrip do
   case some leds might retain their previously set value.
   """
   @spec set_leds(atom, atom, list(pos_integer)) :: :ok | {:error, String.t()}
-  def set_leds(strip_name \\ __MODULE__, namespace, leds) do
+  def set_leds(strip_name, namespace, leds) do
     GenServer.call(strip_name, {:set_leds, namespace, leds})
   end
 
@@ -143,7 +143,7 @@ defmodule Fledex.LedStrip do
   """
   @deprecated "will be replaced with better strip_config right from the beginning"
   @spec change_config(atom, list(atom), any) :: {:ok, any}
-  def change_config(strip_name \\ __MODULE__, config_path, value) do
+  def change_config(strip_name, config_path, value) do
     GenServer.call(strip_name, {:change_config, config_path, value})
   end
 
@@ -153,8 +153,6 @@ defmodule Fledex.LedStrip do
   If you do, you will surely know about it :)
   """
   @spec reinit(atom, module | {module, keyword} | [{module, keyword}], keyword) :: :ok
-  def reinit(strip_name \\ __MODULE__, drivers, strip_config)
-
   def reinit(strip_name, driver, strip_config) when is_atom(driver) do
     reinit(strip_name, {driver, []}, strip_config)
   end
@@ -169,7 +167,7 @@ defmodule Fledex.LedStrip do
   end
 
   @spec stop(GenServer.server()) :: :ok
-  def stop(strip_name \\ __MODULE__) do
+  def stop(strip_name) do
     GenServer.stop(strip_name)
   end
 
diff --git a/lib/fledex/utils/guards.ex b/lib/fledex/utils/guards.ex
new file mode 100644
index 0000000..a4e329c
--- /dev/null
+++ b/lib/fledex/utils/guards.ex
@@ -0,0 +1,25 @@
+# Copyright 2024, Matthias Reik <fledex@reik.org>
+#
+# SPDX-License-Identifier: Apache-2.0
+defmodule Fledex.Utils.Guards do
+  @moduledoc """
+    This module collects all useful guards. If you want to use one of them
+    you need to `import` this module.
+  """
+
+  @doc """
+    This guard checks whether the value is within the given range.
+    Notes:
+
+      * The lower bound is excluded (except if `inverse_bounds` is true)
+      * The upper bound is included (except if `inverse_bounds` is true)
+      * This guard is not fully tested, so be careful when using that it works for you.
+  """
+  # @spec is_in_range(integer, boolean, integer, integer) :: boolean
+  defguard is_in_range(value, inverse_bounds, min, max) when
+    is_integer(value) and
+    (
+      (inverse_bounds and value + 1 > min and value + 1 <= max) or
+      (not inverse_bounds and value > min and value <= max)
+    )
+end
diff --git a/test/fledex/driver/impl/logger_test.exs b/test/fledex/driver/impl/logger_test.exs
index 7b448f8..2b3ffb4 100644
--- a/test/fledex/driver/impl/logger_test.exs
+++ b/test/fledex/driver/impl/logger_test.exs
@@ -66,6 +66,22 @@ defmodule Fledex.Driver.Impl.LoggerTest do
       assert String.contains?(log, ansi_color_b)
     end
 
+    test "transfer without leds" do
+      log = capture_log(fn ->
+        config =
+          Logger.init(
+            update_freq: 1,
+            log_color_code: false,
+            terminal: false
+          )
+
+        leds = []
+        Logger.transfer(leds, 0, config)
+      end)
+
+      assert log == ""
+    end
+
     test "transfer (logger with color code)" do
       capture_log(fn ->
         config =
diff --git a/test/fledex/utils/guards_test.exs b/test/fledex/utils/guards_test.exs
new file mode 100644
index 0000000..6105c82
--- /dev/null
+++ b/test/fledex/utils/guards_test.exs
@@ -0,0 +1,47 @@
+# Copyright 2024, Matthias Reik <fledex@reik.org>
+#
+# SPDX-License-Identifier: Apache-2.0
+defmodule Fledex.Utils.GuardsTest do
+  use ExUnit.Case
+
+  import Fledex.Utils.Guards
+
+  def create_in_range_case(line) do
+    # IO.puts("line: #{inspect line}")
+    line
+      |> String.split(",")
+      |> Enum.map(fn item -> convert!(item) end)
+      |> List.to_tuple()
+  end
+
+  def convert!("t"), do: true
+  def convert!("true"), do: true
+  def convert!("f"), do: false
+  def convert!("false"), do: false
+  def convert!(num), do: String.to_integer(num)
+
+  describe "Test is_in_range" do
+    setup do
+      cases = File.read!("test/fledex/utils/in_range_guard_cases.csv")
+        |> String.split("\n")
+        |> Enum.reject(fn line ->
+          String.length(String.trim(line)) == 0
+        end)
+        |> Enum.map(fn line -> create_in_range_case(line) end)
+      %{cases: cases}
+    end
+    test "test all combinations", %{cases: cases} do
+      Enum.each(cases, fn {value, inverted, min, max, expected} ->
+        # IO.puts("case #{inspect {value, inverted, min, max, expected}}")
+        case value do
+          _x when is_in_range(value, inverted, min, max) ->
+            # IO.puts("in_range")
+            assert(expected)
+          _x when not is_in_range(value, inverted, min, max) ->
+            # IO.puts("NOT in_range")
+            assert(not expected)
+        end
+      end)
+    end
+  end
+end
diff --git a/test/fledex/utils/in_range_guard_cases.csv b/test/fledex/utils/in_range_guard_cases.csv
new file mode 100644
index 0000000..cd8d1f3
--- /dev/null
+++ b/test/fledex/utils/in_range_guard_cases.csv
@@ -0,0 +1,5 @@
+3,f,0,5,t
+0,f,0,5,f
+0,t,0,5,t
+5,f,0,5,t
+5,t,0,5,f
diff --git a/test/fledex/utils/in_range_guard_cases.csv.license b/test/fledex/utils/in_range_guard_cases.csv.license
new file mode 100644
index 0000000..db2df91
--- /dev/null
+++ b/test/fledex/utils/in_range_guard_cases.csv.license
@@ -0,0 +1,3 @@
+Copyright 2024, Matthias Reik <fledex@reik.org>
+
+SPDX-License-Identifier: Apache-2.0
\ No newline at end of file
diff --git a/test/led_strip_test.exs b/test/led_strip_test.exs
index ac6c6c0..dadda51 100644
--- a/test/led_strip_test.exs
+++ b/test/led_strip_test.exs
@@ -410,6 +410,7 @@ defmodule Fledex.LedStripTestSync do
       :ok = GenServer.stop(pid)
       assert {:ok, pid} = LedStrip.start_link(:test_strip_name5, Null, [])
       :ok = GenServer.stop(pid)
+      assert {:error, _} = LedStrip.start_link(:test_strop_name6, %{wrong: "structure"}, [])
     end
 
     test "client API calls", %{strip_name: strip_name} do
@@ -427,6 +428,9 @@ defmodule Fledex.LedStripTestSync do
                  test2: 123
                )
 
+      # test all 3 reinit functions (they all lead to the same result)
+      assert :ok == LedStrip.reinit(strip_name, Fledex.LedStripTest.TestDriver, [])
+      assert :ok == LedStrip.reinit(strip_name, {Fledex.LedStripTest.TestDriver, []}, [])
       assert :ok == LedStrip.reinit(strip_name, [{Fledex.LedStripTest.TestDriver, []}], [])
       assert :ok == LedStrip.drop_namespace(strip_name, @namespace)
       assert :ok == GenServer.stop(strip_name)