diff --git a/src/cocoa_joystick.h b/src/cocoa_joystick.h
index 5a98ea0a..bc38ecc9 100644
--- a/src/cocoa_joystick.h
+++ b/src/cocoa_joystick.h
@@ -39,7 +39,7 @@
 //
 typedef struct _GLFWjoydeviceNS
 {
-    int             present;
+    GLFWbool        present;
     char            name[256];
 
     IOHIDDeviceRef deviceRef;
diff --git a/src/egl_context.c b/src/egl_context.c
index 51fa349b..53aaf6cc 100644
--- a/src/egl_context.c
+++ b/src/egl_context.c
@@ -176,7 +176,7 @@ static GLFWbool chooseFBConfigs(const _GLFWctxconfig* ctxconfig,
 
 // Initialize EGL
 //
-int _glfwInitEGL(void)
+GLFWbool _glfwInitEGL(void)
 {
     int i;
     const char* sonames[] =
@@ -284,9 +284,9 @@ void _glfwTerminateEGL(void)
 
 // Create the OpenGL or OpenGL ES context
 //
-int _glfwCreateContextEGL(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig)
+GLFWbool _glfwCreateContextEGL(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig)
 {
     int attribs[40];
     EGLConfig config;
diff --git a/src/egl_context.h b/src/egl_context.h
index bc535849..b24a4d6c 100644
--- a/src/egl_context.h
+++ b/src/egl_context.h
@@ -207,11 +207,11 @@ typedef struct _GLFWlibraryEGL
 } _GLFWlibraryEGL;
 
 
-int _glfwInitEGL(void);
+GLFWbool _glfwInitEGL(void);
 void _glfwTerminateEGL(void);
-int _glfwCreateContextEGL(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig);
+GLFWbool _glfwCreateContextEGL(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig);
 void _glfwDestroyContextEGL(_GLFWwindow* window);
 #if defined(_GLFW_X11)
 GLFWbool _glfwChooseVisualEGL(const _GLFWctxconfig* ctxconfig,
diff --git a/src/glx_context.c b/src/glx_context.c
index b1c053dc..8e8ccfd1 100644
--- a/src/glx_context.c
+++ b/src/glx_context.c
@@ -150,7 +150,7 @@ static GLXContext createLegacyContext(_GLFWwindow* window,
 
 // Initialize GLX
 //
-int _glfwInitGLX(void)
+GLFWbool _glfwInitGLX(void)
 {
     int i;
     const char* sonames[] =
@@ -314,9 +314,9 @@ void _glfwTerminateGLX(void)
 
 // Create the OpenGL or OpenGL ES context
 //
-int _glfwCreateContextGLX(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig)
+GLFWbool _glfwCreateContextGLX(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig)
 {
     int attribs[40];
     GLXFBConfig native = NULL;
diff --git a/src/glx_context.h b/src/glx_context.h
index 073cd3cd..dc54c797 100644
--- a/src/glx_context.h
+++ b/src/glx_context.h
@@ -171,11 +171,11 @@ typedef struct _GLFWlibraryGLX
 } _GLFWlibraryGLX;
 
 
-int _glfwInitGLX(void);
+GLFWbool _glfwInitGLX(void);
 void _glfwTerminateGLX(void);
-int _glfwCreateContextGLX(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig);
+GLFWbool _glfwCreateContextGLX(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig);
 void _glfwDestroyContextGLX(_GLFWwindow* window);
 GLFWbool _glfwChooseVisualGLX(const _GLFWctxconfig* ctxconfig,
                               const _GLFWfbconfig* fbconfig,
diff --git a/src/internal.h b/src/internal.h
index fd6cd976..206b7e50 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -231,10 +231,10 @@ struct _GLFWfbconfig
     int         accumBlueBits;
     int         accumAlphaBits;
     int         auxBuffers;
-    int         stereo;
+    GLFWbool    stereo;
     int         samples;
-    int         sRGB;
-    int         doublebuffer;
+    GLFWbool    sRGB;
+    GLFWbool    doublebuffer;
 
     // This is defined in the context API's context.h
     _GLFW_PLATFORM_FBCONFIG;
@@ -918,6 +918,6 @@ void _glfwFreeMonitors(_GLFWmonitor** monitors, int count);
 
 /*! @ingroup utility
  */
-int _glfwIsPrintable(int key);
+GLFWbool _glfwIsPrintable(int key);
 
 #endif // _glfw3_internal_h_
diff --git a/src/linux_joystick.c b/src/linux_joystick.c
index 0b6328a1..aff9eda6 100644
--- a/src/linux_joystick.c
+++ b/src/linux_joystick.c
@@ -173,7 +173,7 @@ static GLFWbool pollJoystickEvents(_GLFWjoystickLinux* js)
 
 // Initialize joystick interface
 //
-int _glfwInitJoysticksLinux(void)
+GLFWbool _glfwInitJoysticksLinux(void)
 {
 #if defined(__linux__)
     const char* dirname = "/dev/input";
diff --git a/src/linux_joystick.h b/src/linux_joystick.h
index 25a893ef..6f34d576 100644
--- a/src/linux_joystick.h
+++ b/src/linux_joystick.h
@@ -36,7 +36,7 @@
 //
 typedef struct _GLFWjoystickLinux
 {
-    int             present;
+    GLFWbool        present;
     int             fd;
     float*          axes;
     int             axisCount;
@@ -61,7 +61,7 @@ typedef struct _GLFWjoylistLinux
 } _GLFWjoylistLinux;
 
 
-int _glfwInitJoysticksLinux(void);
+GLFWbool _glfwInitJoysticksLinux(void);
 void _glfwTerminateJoysticksLinux(void);
 
 #endif // _glfw3_linux_joystick_h_
diff --git a/src/nsgl_context.h b/src/nsgl_context.h
index 82fde269..6a0a22fd 100644
--- a/src/nsgl_context.h
+++ b/src/nsgl_context.h
@@ -52,11 +52,11 @@ typedef struct _GLFWlibraryNSGL
 } _GLFWlibraryNSGL;
 
 
-int _glfwInitNSGL(void);
+GLFWbool _glfwInitNSGL(void);
 void _glfwTerminateNSGL(void);
-int _glfwCreateContextNSGL(_GLFWwindow* window,
-                           const _GLFWctxconfig* ctxconfig,
-                           const _GLFWfbconfig* fbconfig);
+GLFWbool _glfwCreateContextNSGL(_GLFWwindow* window,
+                                const _GLFWctxconfig* ctxconfig,
+                                const _GLFWfbconfig* fbconfig);
 void _glfwDestroyContextNSGL(_GLFWwindow* window);
 
 #endif // _glfw3_nsgl_context_h_
diff --git a/src/nsgl_context.m b/src/nsgl_context.m
index dbca3797..714d5272 100644
--- a/src/nsgl_context.m
+++ b/src/nsgl_context.m
@@ -33,7 +33,7 @@
 
 // Initialize OpenGL support
 //
-int _glfwInitNSGL(void)
+GLFWbool _glfwInitNSGL(void)
 {
     _glfw.nsgl.framework =
         CFBundleGetBundleWithIdentifier(CFSTR("com.apple.opengl"));
@@ -55,9 +55,9 @@ void _glfwTerminateNSGL(void)
 
 // Create the OpenGL context
 //
-int _glfwCreateContextNSGL(_GLFWwindow* window,
-                           const _GLFWctxconfig* ctxconfig,
-                           const _GLFWfbconfig* fbconfig)
+GLFWbool _glfwCreateContextNSGL(_GLFWwindow* window,
+                                const _GLFWctxconfig* ctxconfig,
+                                const _GLFWfbconfig* fbconfig)
 {
     unsigned int attributeCount = 0;
 
diff --git a/src/wgl_context.c b/src/wgl_context.c
index 291bb9c8..55138e70 100644
--- a/src/wgl_context.c
+++ b/src/wgl_context.c
@@ -287,7 +287,7 @@ static GLFWbool isCompositionEnabled(void)
 
 // Initialize WGL
 //
-int _glfwInitWGL(void)
+GLFWbool _glfwInitWGL(void)
 {
     _glfw.wgl.instance = LoadLibraryA("opengl32.dll");
     if (!_glfw.wgl.instance)
@@ -327,9 +327,9 @@ void _glfwTerminateWGL(void)
 
 // Create the OpenGL or OpenGL ES context
 //
-int _glfwCreateContextWGL(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig)
+GLFWbool _glfwCreateContextWGL(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig)
 {
     int attribs[40];
     int pixelFormat = 0;
diff --git a/src/wgl_context.h b/src/wgl_context.h
index 0523cee4..bc8968b4 100644
--- a/src/wgl_context.h
+++ b/src/wgl_context.h
@@ -144,11 +144,11 @@ typedef struct _GLFWlibraryWGL
 } _GLFWlibraryWGL;
 
 
-int _glfwInitWGL(void);
+GLFWbool _glfwInitWGL(void);
 void _glfwTerminateWGL(void);
-int _glfwCreateContextWGL(_GLFWwindow* window,
-                          const _GLFWctxconfig* ctxconfig,
-                          const _GLFWfbconfig* fbconfig);
+GLFWbool _glfwCreateContextWGL(_GLFWwindow* window,
+                               const _GLFWctxconfig* ctxconfig,
+                               const _GLFWfbconfig* fbconfig);
 void _glfwDestroyContextWGL(_GLFWwindow* window);
 int _glfwAnalyzeContextWGL(_GLFWwindow* window,
                            const _GLFWctxconfig* ctxconfig,