@static if Sys.isapple()
    # OpenGL 3.2 + GLSL 150
    const glsl_version = 150
    GLFW.WindowHint(GLFW.CONTEXT_VERSION_MAJOR, 3)
    GLFW.WindowHint(GLFW.CONTEXT_VERSION_MINOR, 2)
    GLFW.WindowHint(GLFW.OPENGL_PROFILE, GLFW.OPENGL_CORE_PROFILE) # 3.2+ only
    GLFW.WindowHint(GLFW.OPENGL_FORWARD_COMPAT, GL_TRUE) # required on Mac
else
    # OpenGL 3.0 + GLSL 130
    const glsl_version = 130
    GLFW.WindowHint(GLFW.CONTEXT_VERSION_MAJOR, 3)
    GLFW.WindowHint(GLFW.CONTEXT_VERSION_MINOR, 0)
    # GLFW.WindowHint(GLFW.OPENGL_PROFILE, GLFW.OPENGL_CORE_PROFILE) # 3.2+ only
    # GLFW.WindowHint(GLFW.OPENGL_FORWARD_COMPAT, GL_TRUE) # 3.0+ only
end

# setup GLFW error callback
error_callback(err::GLFW.GLFWError) = @error "GLFW ERROR: code $(err.code) msg: $(err.description)"
GLFW.SetErrorCallback(error_callback)
