diff --git a/lib/qr_code/data_encoding/common.ex b/lib/qr_code/data_encoding/common.ex
index 95c704e..fcfcbd1 100644
--- a/lib/qr_code/data_encoding/common.ex
+++ b/lib/qr_code/data_encoding/common.ex
@@ -57,7 +57,7 @@ defmodule QRCode.DataEncoding.Common do
   end
 
   defp add_specification(fill_to_max) do
-    1..fill_to_max
+    1..fill_to_max//1
     |> Enum.map(fn x -> rem(x, 2) end)
     |> Enum.reduce(<<>>, fn
       x, acc when x == 0 -> acc <> <<17>>
diff --git a/lib/qr_code/data_masking.ex b/lib/qr_code/data_masking.ex
index 6e31113..af810d6 100644
--- a/lib/qr_code/data_masking.ex
+++ b/lib/qr_code/data_masking.ex
@@ -25,7 +25,7 @@ defmodule QRCode.DataMasking do
 
   @spec masking_matrices(Matrix.t()) :: Enumerable.t()
   def masking_matrices(matrix) do
-    Stream.map(0..7, fn num -> {num, make_mask_pattern(matrix, num)} end)
+    Stream.map(0..7//1, fn num -> {num, make_mask_pattern(matrix, num)} end)
   end
 
   @spec total_penalties(Enumerable.t()) :: Enumerable.t()
@@ -44,7 +44,7 @@ defmodule QRCode.DataMasking do
 
   @spec total_penalty(Matrix.t()) :: pos_integer()
   def total_penalty(matrix) do
-    Enum.reduce(1..4, 0, fn pen, sum -> penalty(matrix, pen) + sum end)
+    Enum.reduce(1..4//1, 0, fn pen, sum -> penalty(matrix, pen) + sum end)
   end
 
   @spec penalty(Matrix.t(), 1 | 2 | 3 | 4) :: non_neg_integer()
diff --git a/lib/qr_code/galois_field.ex b/lib/qr_code/galois_field.ex
index 0ec76df..977dce2 100644
--- a/lib/qr_code/galois_field.ex
+++ b/lib/qr_code/galois_field.ex
@@ -272,7 +272,7 @@ defmodule QRCode.GaloisField do
       2
   """
   @spec to_i(alpha()) :: value()
-  def to_i(alpha) when alpha in 0..254 do
+  def to_i(alpha) when alpha in 0..254//1 do
     @gf_table
     |> Enum.find(fn {_i, a} -> alpha == a end)
     |> first()
@@ -285,7 +285,7 @@ defmodule QRCode.GaloisField do
       1
   """
   @spec to_a(value()) :: alpha()
-  def to_a(integer) when integer in 1..255 do
+  def to_a(integer) when integer in 1..255//1 do
     @gf_table
     |> Enum.find(fn {i, _a} -> integer == i end)
     |> second()
diff --git a/lib/qr_code/generator_polynomial.ex b/lib/qr_code/generator_polynomial.ex
index 708baff..8ae215c 100644
--- a/lib/qr_code/generator_polynomial.ex
+++ b/lib/qr_code/generator_polynomial.ex
@@ -30,7 +30,7 @@ defmodule QRCode.GeneratorPolynomial do
       [0, 251, 67, 46, 61, 118, 70, 64, 94, 32, 45]
   """
   @spec create(degree()) :: polynomial()
-  def create(degree) when is_integer(degree) and degree in 1..254 do
+  def create(degree) when is_integer(degree) and degree in 1..254//1 do
     degree
     |> roots()
     |> Enum.reduce(&multiply/2)
diff --git a/lib/qr_code/placement.ex b/lib/qr_code/placement.ex
index d12bde2..e585309 100644
--- a/lib/qr_code/placement.ex
+++ b/lib/qr_code/placement.ex
@@ -180,7 +180,7 @@ defmodule QRCode.Placement do
   end
 
   defp fill_matrix_by_message(matrix, size, message) do
-    (size - 1)..7
+    (size - 1)..7//-1
     |> Enum.take_every(2)
     |> Enum.concat([5, 3, 1])
     |> Enum.map_reduce({matrix, message}, fn col, acc ->
diff --git a/lib/qr_code/qr.ex b/lib/qr_code/qr.ex
index c119fdd..c5d510d 100644
--- a/lib/qr_code/qr.ex
+++ b/lib/qr_code/qr.ex
@@ -44,8 +44,8 @@ defmodule QRCode.QR do
 
   defguard level(lvl) when lvl in @levels
   defguard mode(m) when m in @modes
-  defguard version(v) when v in 1..40
-  defguard masking(m) when m in 0..7
+  defguard version(v) when v in 1..40//1
+  defguard masking(m) when m in 0..7//1
 
   @doc """
   Creates QR code. You can change the error correction level according to your needs.
diff --git a/test/generator_polynomial_test.exs b/test/generator_polynomial_test.exs
index 26f93b8..550a33f 100644
--- a/test/generator_polynomial_test.exs
+++ b/test/generator_polynomial_test.exs
@@ -11,7 +11,7 @@ defmodule GeneratorPolynomialTest do
     forall degree <- integer(1, 254) do
       poly = GP.create(degree)
 
-      assert Enum.all?(poly, fn x -> x in 0..254 end)
+      assert Enum.all?(poly, fn x -> x in 0..254//1 end)
     end
   end
 
diff --git a/test/placement_test.exs b/test/placement_test.exs
index 01d554a..30b44ae 100644
--- a/test/placement_test.exs
+++ b/test/placement_test.exs
@@ -15,7 +15,7 @@ defmodule PlacementTest do
   describe "Placement" do
     test "should check if finder patterns have correct position at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -34,7 +34,7 @@ defmodule PlacementTest do
 
     test "should check if separator patterns have correct position at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -53,7 +53,7 @@ defmodule PlacementTest do
 
     test "should check if reserved areas have correct position at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -72,7 +72,7 @@ defmodule PlacementTest do
 
     test "should check if timing patterns have correct position at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -91,7 +91,7 @@ defmodule PlacementTest do
 
     test "should check if alignment patterns have correct positions at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -110,7 +110,7 @@ defmodule PlacementTest do
 
     test "should check if dark modules have correct position at qr matrix" do
       tasks =
-        for version <- 1..40 do
+        for version <- 1..40//1 do
           Task.async(fn ->
             size = 4 * version + 17
 
@@ -143,7 +143,7 @@ defmodule PlacementTest do
     size = 4 * version + 16
 
     {:ok, [hd | rest]} =
-      size..7
+      size..7//-1
       |> Enum.take_every(2)
       |> Enum.concat([5, 3, 1])
       |> Enum.reverse()