diff --git a/src/termbox/bindings.cr b/src/termbox/bindings.cr
index 24aa982..cfcca99 100644
--- a/src/termbox/bindings.cr
+++ b/src/termbox/bindings.cr
@@ -27,18 +27,18 @@ lib TermboxBindings
   end
 
   # API
-  fun tb_init(): Int
+  fun tb_init(): Int32
   fun tb_shutdown(): Void
-  fun tb_width(): Int
-  fun tb_height(): Int
+  fun tb_width(): Int32
+  fun tb_height(): Int32
   fun tb_clear(): Void
   fun tb_set_clear_attributes(fg: UInt16, bg: UInt16): Void
   fun tb_present(): Void
-  fun tb_set_cursor(x: Int, y: Int): Void
-  fun tb_put_cell(x: Int, y: Int, cell: Pointer(Cell)): Void
-  fun tb_change_cell(x: Int, y: Int, ch: UInt32, fg: UInt16, bg: UInt16): Void
-  fun tb_select_input_mode(mode: Int): Int
-  fun tb_select_output_mode(mode: Int): Int
-  fun tb_peek_event(event: Pointer(Event), timeout: Int): Int
-  fun tb_poll_event(event: Pointer(Event)): Int
+  fun tb_set_cursor(x: Int32, y: Int32): Void
+  fun tb_put_cell(x: Int32, y: Int32, cell: Pointer(Cell)): Void
+  fun tb_change_cell(x: Int32, y: Int32, ch: UInt32, fg: UInt16, bg: UInt16): Void
+  fun tb_select_input_mode(mode: Int32): Int32
+  fun tb_select_output_mode(mode: Int32): Int32
+  fun tb_peek_event(event: Pointer(Event), timeout: Int32): Int32
+  fun tb_poll_event(event: Pointer(Event)): Int32
 end
diff --git a/src/termbox/border.cr b/src/termbox/border.cr
index d77e24c..c13301d 100644
--- a/src/termbox/border.cr
+++ b/src/termbox/border.cr
@@ -18,7 +18,7 @@ module Termbox
     end
 
     # For special-mode borders (normal, double, solid, cloth_low, cloth_med, cloth_high, dotted)
-    def initialize(pivot : Position, width : Int, height : Int, mode : String)
+    def initialize(pivot : Position, width : Int32, height : Int32, mode : String)
       # Decide on border character given mode
       # For normal/double/char modes, just use X (no use)
       case mode
@@ -40,17 +40,17 @@ module Termbox
     end
 
     # Normal mode
-    def initialize(pivot : Position, width : Int, height : Int)
+    def initialize(pivot : Position, width : Int32, height : Int32)
       initialize(pivot, width, height, "normal")
     end
 
     # Border based on a single character
-    def initialize(pivot : Position, width : Int, height : Int, char : Char)
+    def initialize(pivot : Position, width : Int32, height : Int32, char : Char)
       initialize(pivot, width, height, "char", char)
     end
 
     # Master internal constructor
-    private def initialize(@pivot : Position, @width : Int, @height : Int, @mode : String, @char : Char)
+    private def initialize(@pivot : Position, @width : Int32, @height : Int32, @mode : String, @char : Char)
       @foreground = COLOR_NIL
       @background = COLOR_NIL
     end
diff --git a/src/termbox/cell.cr b/src/termbox/cell.cr
index 3215fec..59bc815 100644
--- a/src/termbox/cell.cr
+++ b/src/termbox/cell.cr
@@ -6,7 +6,7 @@ module Termbox
     getter :position, :char, :foreground, :background
 
     # Make a cell with a specified foreground and background
-    def initialize(@char : Char, @position : Position, @foreground : Int, @background : Int)
+    def initialize(@char : Char, @position : Position, @foreground : Int32, @background : Int32)
     end
 
     # Make a cell with default colors
@@ -15,7 +15,7 @@ module Termbox
     end
 
     # Make a new cell with a position transformed by x and y
-    def new_transform(x : Int, y : Int)
+    def new_transform(x : Int32, y : Int32)
       Cell.new(@char, @position.new_transform(x, y), @foreground, @background)
     end
 
diff --git a/src/termbox/container.cr b/src/termbox/container.cr
index aa0f18b..58208d2 100644
--- a/src/termbox/container.cr
+++ b/src/termbox/container.cr
@@ -7,7 +7,7 @@ module Termbox
     getter :elements
 
     # Accepts a pivot (top left position), width, and height
-    def initialize(@pivot : Position, @width : Int, @height : Int)
+    def initialize(@pivot : Position, @width : Int32, @height : Int32)
       @elements = [] of Element
     end
 
diff --git a/src/termbox/line.cr b/src/termbox/line.cr
index 925532b..e3f9fa8 100644
--- a/src/termbox/line.cr
+++ b/src/termbox/line.cr
@@ -4,7 +4,7 @@ module Termbox
   class Line < Termbox::Element
     getter :cell, :size, :is_vertical
 
-    def initialize(@cell : Cell, @size : Int, @is_vertical : Bool = true)
+    def initialize(@cell : Cell, @size : Int32, @is_vertical : Bool = true)
     end
 
     def render : Array(Cell)
diff --git a/src/termbox/position.cr b/src/termbox/position.cr
index a59561c..ea31b90 100644
--- a/src/termbox/position.cr
+++ b/src/termbox/position.cr
@@ -3,10 +3,10 @@ module Termbox
   struct Position
     getter :x, :y
 
-    def initialize(@x : Int, @y : Int)
+    def initialize(@x : Int32, @y : Int32)
     end
 
-    def new_transform(x : Int, y : Int)
+    def new_transform(x : Int32, y : Int32)
       Position.new(@x + x, @y + y)
     end
   end
diff --git a/src/termbox/window.cr b/src/termbox/window.cr
index 58f206a..e8bcf26 100644
--- a/src/termbox/window.cr
+++ b/src/termbox/window.cr
@@ -41,12 +41,12 @@ module Termbox
     end
 
     # Get width of termbox
-    def width : Int
+    def width : Int32
       TermboxBindings.tb_width()
     end
 
     # Get height of termbox
-    def height : Int
+    def height : Int32
       TermboxBindings.tb_height()
     end
 
@@ -106,7 +106,7 @@ module Termbox
     end
 
     # Put a decomposed cell and decomposed position, bypassing @elements store
-    private def put_raw(x : Int, y : Int, ch : Int, foreground : Int, background : Int) : Void
+    private def put_raw(x : Int32, y : Int32, ch : Int32, foreground : Int32, background : Int32) : Void
       TermboxBindings.tb_change_cell(x, y, ch, foreground, background)
     end
 
@@ -116,17 +116,17 @@ module Termbox
     end
 
     # Set input mode
-    def set_input_mode(mode : Int) : Int
+    def set_input_mode(mode : Int32) : Int32
       TermboxBindings.tb_select_input_mode(mode)
     end
 
     # Set output mode
-    def set_output_mode(mode : Int) : Int
+    def set_output_mode(mode : Int32) : Int32
       TermboxBindings.tb_select_output_mode(mode)
     end
 
     # Set primary colors
-    def set_primary_colors(foreground : Int, background : Int) : Void
+    def set_primary_colors(foreground : Int32, background : Int32) : Void
       @foreground = foreground
       @background = background
       TermboxBindings.tb_set_clear_attributes(foreground, background)
@@ -139,7 +139,7 @@ module Termbox
 
     # Events
 
-    def peek(timeout : Int)
+    def peek(timeout : Int32)
       e = @event_master
       TermboxBindings.tb_peek_event(pointerof(e), timeout)
       e
@@ -159,19 +159,19 @@ module Termbox
     end
 
     # Write a string horizontal starting at pivot
-    def write_string(pivot : Position, string : String, foreground : Int, background : Int)
+    def write_string(pivot : Position, string : String, foreground : Int32, background : Int32)
       string.each_char_with_index do |char, i|
         put_raw(pivot.new_transform(i, 0), char, foreground, background)
       end
     end
     
     # Decide on foreground (if nil, use default)
-    private def decide_foreground(color : Int)
+    private def decide_foreground(color : Int32)
       color != COLOR_NIL ? color : @foreground
     end
 
     # Decide on background (if nil, use default)
-    private def decide_background(color : Int)
+    private def decide_background(color : Int32)
       color != COLOR_NIL ? color : @background
     end
   end