diff --git a/new/unix/OLDcontainer.c b/new/unix/OLDcontainer.c
new file mode 100644
index 00000000..254865ae
--- /dev/null
+++ b/new/unix/OLDcontainer.c
@@ -0,0 +1,72 @@
+// 13 august 2014
+#include "uipriv_unix.h"
+
+#define gtkXPadding 12
+#define gtkYPadding 6
+
+static void uipOSContainer_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
+{
+	uipOSContainer *c = uipOSContainer(widget);
+	uiSizing d;
+	intmax_t x, y, width, height;
+
+	gtk_widget_set_allocation(GTK_WIDGET(c), allocation);
+	if (c->mainControl == NULL)
+		return;
+	x = allocation->x + c->marginLeft;
+	y = allocation->y + c->marginTop;
+	width = allocation->width - (c->marginLeft + c->marginRight);
+	height = allocation->height - (c->marginTop + c->marginBottom);
+	d.xPadding = gtkXPadding;
+	d.yPadding = gtkYPadding;
+	uiControlResize(c->mainControl, x, y, width, height, &d);
+}
+
+
+
+// TODO convert other methods of other backends to pp arg p instance variable
+
+static void parentDestroy(uiOSContainer *cc)
+{
+	uipOSContainer *c = uipOSContainer(cc->Internal);
+
+	// first, destroy the main control
+	if (c->mainControl != NULL) {
+		// we have to do this before we can destroy controls
+		uiControlSetHasParent(c->mainControl, 0);
+		uiControlSetOSContainer(c->mainControl, NULL);
+		uiControlDestroy(c->mainControl);
+		c->mainControl = NULL;
+	}
+	// now we can mark the parent as ready to be destroyed
+	c->canDestroy = TRUE;
+	// finally, destroy the parent
+	g_object_unref(G_OBJECT(c));
+	// and free ourselves
+	uiFree(cc);
+}
+
+static void parentSetMainControl(uiOSContainer *cc, uiControl *mainControl)
+{
+	uipOSContainer *c = uipOSContainer(cc->Internal);
+
+	if (c->mainControl != NULL) {
+		uiControlSetHasParent(c->mainControl, 0);
+		uiControlSetOSContainer(c->mainControl, NULL);
+	}
+	c->mainControl = mainControl;
+	if (c->mainControl != NULL) {
+		uiControlSetHasParent(c->mainControl, 1);
+		uiControlSetOSContainer(c->mainControl, cc);
+	}
+}
+
+static void parentSetMargins(uiOSContainer *cc, intmax_t left, intmax_t top, intmax_t right, intmax_t bottom)
+{
+	uipOSContainer *c = uipOSContainer(cc->Internal);
+
+	c->marginLeft = left;
+	c->marginTop = top;
+	c->marginRight = right;
+	c->marginBottom = bottom;
+}
diff --git a/new/unix/container.c b/new/unix/container.c
new file mode 100644
index 00000000..4b537a51
--- /dev/null
+++ b/new/unix/container.c
@@ -0,0 +1,234 @@
+// 28 april 2015
+#include "uipriv_unix.h"
+
+#define containerWidgetType (containerWidget_get_type())
+#define containerWidget(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj), containerWidgetType, containerWidget))
+#define IscontainerWidget(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj), containerWidgetType))
+#define containerWidgetClass(class) (G_TYPE_CHECK_CLASS_CAST((class), containerWidgetType, containerWidgetClass))
+#define IscontainerWidgetClass(class) (G_TYPE_CHECK_CLASS_TYPE((class), containerWidget))
+#define GetcontainerWidgetClass(obj) (G_TYPE_INSTANCE_GET_CLASS((obj), containerWidgetType, containerWidgetClass))
+
+typedef struct containerWidget containerWidget;
+typedef struct containerWidgetClass containerWidgetClass;
+
+struct containerWidget {
+	GtkContainer parent_instance;
+	uiContainer *c;
+	GPtrArray *widgets;		// for for_each()/for_all()
+	uiContainer *parent;
+	int hidden;
+};
+
+struct containerWidgetClass {
+	GtkContainerClass parent_class;
+};
+
+G_DEFINE_TYPE(containerWidget, containerWidget, GTK_TYPE_CONTAINER)
+
+static void containerWidget_init(containerWidget *c)
+{
+	if (options.debugLogAllocations)
+		fprintf(stderr, "%p alloc containerWidget\n", c);
+	c->widgets = g_ptr_array_new();
+	gtk_widget_set_has_window(GTK_WIDGET(c), FALSE);
+}
+
+// TODO destroy blocking
+static void containerWidget_dispose(GObject *obj)
+{
+	G_OBJECT_CLASS(containerWidget_parent_class)->dispose(obj);
+}
+
+static void containerWidget_finalize(GObject *obj)
+{
+	containerWidget *c = containerWidget(obj);
+
+	g_ptr_array_unref(c->widgets);
+	G_OBJECT_CLASS(containerWidget_parent_class)->finalize(obj);
+	if (options.debugLogAllocations)
+		fprintf(stderr, "%p free\n", obj);
+}
+
+static void containerWidget_add(GtkContainer *container, GtkWidget *widget)
+{
+	containerWidget *c = containerWidget(container);
+
+	gtk_widget_set_parent(widget, GTK_WIDGET(c));
+	g_ptr_array_add(c->widgets, widget);
+}
+
+static void containerWidget_remove(GtkContainer *container, GtkWidget *widget)
+{
+	containerWidget *c = containerWidget(container);
+
+	gtk_widget_unparent(widget);
+	if (g_ptr_array_remove(c->widgets, widget) == FALSE)
+		complain("widget %p not found in containerWidget gtk_container_remove()", widget);
+}
+
+static void containerWidget_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
+{
+	containerWidget *c = containerWidget(widget);
+	uiSizing d;
+
+	gtk_widget_set_allocation(GTK_WIDGET(c), allocation);
+	d.xPadding = gtkXPadding;
+	d.yPadding = gtkYPadding;
+	uiContainerResizeChildren(c->c, allocation->x, allocation->y, allocation->width, allocation->height, &d);
+}
+
+struct forall {
+	GtkCallback callback;
+	gpointer data;
+};
+
+static void doforall(gpointer obj, gpointer data)
+{
+	struct forall *s = (struct forall *) data;
+
+	(*(s->callback))(GTK_WIDGET(obj), s->data);
+}
+
+static void uipOSContainer_forall(GtkContainer *container, gboolean includeInternals, GtkCallback callback, gpointer data)
+{
+	uipOSContainer *c = uipOSContainer(container);
+	struct forall s;
+
+	s.callback = callback;
+	s.data = data;
+	g_ptr_array_foreach(c->widgets, doforall, &s);
+}
+
+static void containerWidget_class_init(containerWidgetClass *class)
+{
+	G_OBJECT_CLASS(class)->dispose = containerWidget_dispose;
+	G_OBJECT_CLASS(class)->finalize = containerWidget_finalize;
+	GTK_WIDGET_CLASS(class)->size_allocate = containerWidget_size_allocate;
+	GTK_CONTAINER_CLASS(class)->add = containerWidget_add;
+	GTK_CONTAINER_CLASS(class)->remove = containerWidget_remove;
+	GTK_CONTAINER_CLASS(class)->forall = containerWidget_forall;
+}
+
+// subclasses override this and call back here when all children are destroyed
+static void containerDestroy(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	if (c->parent != NULL)
+		complain("attempt to destroy uiContainer %p while it has a parent", cc);
+	g_object_unref(c);		// release our initial reference, which destroys the widget
+	uiFree(c);
+}
+
+static uintptr_t containerHandle(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	return (uintptr_t) c;
+}
+
+static void containerSetParent(uiControl *cc, uiContainer *parent)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+	uiContainer *oldparent;
+	GtkContainer *oldcontainer;
+	GtkContainer *newcontainer;
+
+	oldparent = c->parent;
+	c->parent = parent;
+	if (oldparent != NULL) {
+		oldcontainer = GTK_CONTAINER(uiControlHandle(uiControl(oldparent)));
+		gtk_container_remove(oldcontainer, GTK_WIDGET(c));
+	}
+	if (c->parent != NULL) {
+		newcontainer = GTK_CONTAINER(uiControlHandle(uiControl(c->parent)));
+		gtk_container_add(newcontainer, GTK_WIDGET(c));
+	}
+	if (oldparent != NULL)
+		uiContainerUpdate(oldparent);
+	if (c->parent != NULL)
+		uiContainerUpdate(c->parent);
+}
+
+static void containerResize(uiControl *cc, intmax_t x, intmax_t y, intmax_t width, intmax_t height, uiSizing *d)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+	GtkAllocation a;
+
+	a.x = x;
+	a.y = y;
+	a.width = width;
+	a.height = height;
+	gtk_widget_size_allocate(GTK_WIDGET(c), &a);
+}
+
+static int containerVisible(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	return !c->hidden;
+}
+
+static void containerShow(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	// don't use gtk_widget_show_all(); that'll show every widget, including ones hidden by the user
+	gtk_widget_show(GTK_WIDGET(c));
+	c->hidden = 0;
+}
+
+static void containerHide(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	gtk_widget_hide(GTK_WIDGET(c));
+	c->hidden = 1;
+}
+
+static void containerEnable(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	gtk_widget_set_sensitive(GTK_WIDGET(c), TRUE);
+}
+
+static void containerDisable(uiControl *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	gtk_widget_set_sensitive(GTK_WIDGET(c), FALSE);
+}
+
+static void containerUpdate(uiContainer *cc)
+{
+	containerWidget *c = containerWidget(cc->Internal);
+
+	gtk_widget_queue_resize(GTK_WIDGET(c));
+}
+
+void uiMakeContainer(uiContainer *cc)
+{
+	containerWidget *c;
+
+	c = containerWidget(g_object_new(containerWidgetType, NULL));
+	// keep a reference to our container so it stays alive when reparented
+	g_object_ref_sink(c);
+	// and make it visible
+	gtk_widget_show_all(GTK_WIDGET(c));
+
+	uiControl(cc)->Internal = c;
+	uiControl(cc)->Destroy = containerDestroy;
+	uiControl(cc)->Handle = containerHandle;
+	uiControl(cc)->SetParent = containerSetParent;
+	// PreferredSize() is provided by subclasses
+	uiControl(cc)->Resize = containerResize;
+	uiControl(cc)->Visible = containerVisible;
+	uiControl(cc)->Show = containerShow;
+	uiControl(cc)->Hide = containerHide;
+	uiControl(cc)->Enable = containerEnable;
+	uiControl(cc)->Disable = containerDisable;
+
+	// ResizeChildren() is provided by subclasses
+	uiContainer(cc)->Update = containerUpdate;
+}
diff --git a/new/unix/oscontainer.c b/new/unix/oscontainer.c
deleted file mode 100644
index a690a63a..00000000
--- a/new/unix/oscontainer.c
+++ /dev/null
@@ -1,219 +0,0 @@
-// 13 august 2014
-#include "uipriv_unix.h"
-
-#define uipOSContainerType (uipOSContainer_get_type())
-#define uipOSContainer(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj), uipOSContainerType, uipOSContainer))
-#define uipIsOSContainer(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj), uipOSContainerType))
-#define uipOSContainerClass(class) (G_TYPE_CHECK_CLASS_CAST((class), uipOSContainerType, uipOSContainerClass))
-#define uipIsOSContainerClass(class) (G_TYPE_CHECK_CLASS_TYPE((class), uipOSContainer))
-#define uipGetParentClass(obj) (G_TYPE_INSTANCE_GET_CLASS((obj), uipOSContainerType, uipOSContainerClass))
-
-typedef struct uipOSContainer uipOSContainer;
-typedef struct uipOSContainerClass uipOSContainerClass;
-
-struct uipOSContainer {
-	GtkContainer parent_instance;
-	uiControl *mainControl;
-	GPtrArray *children;		// for forall()
-	intmax_t marginLeft;
-	intmax_t marginTop;
-	intmax_t marginRight;
-	intmax_t marginBottom;
-	gboolean canDestroy;
-};
-
-struct uipOSContainerClass {
-	GtkContainerClass parent_class;
-};
-
-G_DEFINE_TYPE(uipOSContainer, uipOSContainer, GTK_TYPE_CONTAINER)
-
-static void uipOSContainer_init(uipOSContainer *c)
-{
-	if (options.debugLogAllocations)
-		fprintf(stderr, "%p alloc uipOSContainer\n", c);
-	c->children = g_ptr_array_new();
-	gtk_widget_set_has_window(GTK_WIDGET(c), FALSE);
-}
-
-// instead of having GtkContainer itself unref all our controls, we'll run our own uiControlDestroy() functions for child, which will do that and more
-// we still chain up because we need to, but by that point there will be no children for GtkContainer to free
-static void uipOSContainer_dispose(GObject *obj)
-{
-	uipOSContainer *c = uipOSContainer(obj);
-
-	// don't free mainControl here; that should have been done by uiOSContainerDestroy()
-	if (!c->canDestroy)
-		complain("attempt to dispose uiOSContainer with uipOSContainer at %p before uiOSContainerDestroy()", c);
-	if (c->children != NULL) {
-		if (c->children->len != 0)
-			complain("disposing uiOSContainer with uipOSContainer at %p while there are still children", c);
-		g_ptr_array_unref(c->children);
-		c->children = NULL;
-	}
-	G_OBJECT_CLASS(uipOSContainer_parent_class)->dispose(obj);
-}
-
-static void uipOSContainer_finalize(GObject *obj)
-{
-	uipOSContainer *c = uipOSContainer(obj);
-
-	if (!c->canDestroy)
-		complain("attempt to finalize uiOSContainer with uipOSContainer at %p before uiOSContainerDestroy()", c);
-	G_OBJECT_CLASS(uipOSContainer_parent_class)->finalize(obj);
-	if (options.debugLogAllocations)
-		fprintf(stderr, "%p free\n", obj);
-}
-
-static void uipOSContainer_add(GtkContainer *container, GtkWidget *widget)
-{
-	uipOSContainer *c = uipOSContainer(container);
-
-	gtk_widget_set_parent(widget, GTK_WIDGET(c));
-	if (c->children != NULL)
-		g_ptr_array_add(c->children, widget);
-}
-
-static void uipOSContainer_remove(GtkContainer *container, GtkWidget *widget)
-{
-	uipOSContainer *c = uipOSContainer(container);
-
-	gtk_widget_unparent(widget);
-	if (c->children != NULL)
-		if (g_ptr_array_remove(c->children, widget) == FALSE)
-			complain("widget %p not found in uipOSContainer gtk_container_remove()", widget);
-}
-
-#define gtkXPadding 12
-#define gtkYPadding 6
-
-static void uipOSContainer_size_allocate(GtkWidget *widget, GtkAllocation *allocation)
-{
-	uipOSContainer *c = uipOSContainer(widget);
-	uiSizing d;
-	intmax_t x, y, width, height;
-
-	gtk_widget_set_allocation(GTK_WIDGET(c), allocation);
-	if (c->mainControl == NULL)
-		return;
-	x = allocation->x + c->marginLeft;
-	y = allocation->y + c->marginTop;
-	width = allocation->width - (c->marginLeft + c->marginRight);
-	height = allocation->height - (c->marginTop + c->marginBottom);
-	d.xPadding = gtkXPadding;
-	d.yPadding = gtkYPadding;
-	uiControlResize(c->mainControl, x, y, width, height, &d);
-}
-
-struct forall {
-	GtkCallback callback;
-	gpointer data;
-};
-
-static void doforall(gpointer obj, gpointer data)
-{
-	struct forall *s = (struct forall *) data;
-
-	(*(s->callback))(GTK_WIDGET(obj), s->data);
-}
-
-static void uipOSContainer_forall(GtkContainer *container, gboolean includeInternals, GtkCallback callback, gpointer data)
-{
-	uipOSContainer *c = uipOSContainer(container);
-	struct forall s;
-
-	s.callback = callback;
-	s.data = data;
-	if (c->children != NULL)
-		g_ptr_array_foreach(c->children, doforall, &s);
-}
-
-static void uipOSContainer_class_init(uipOSContainerClass *class)
-{
-	G_OBJECT_CLASS(class)->dispose = uipOSContainer_dispose;
-	G_OBJECT_CLASS(class)->finalize = uipOSContainer_finalize;
-	GTK_WIDGET_CLASS(class)->size_allocate = uipOSContainer_size_allocate;
-	GTK_CONTAINER_CLASS(class)->add = uipOSContainer_add;
-	GTK_CONTAINER_CLASS(class)->remove = uipOSContainer_remove;
-	GTK_CONTAINER_CLASS(class)->forall = uipOSContainer_forall;
-}
-
-// TODO convert other methods of other backends to pp arg p instance variable
-
-static void parentDestroy(uiOSContainer *cc)
-{
-	uipOSContainer *c = uipOSContainer(cc->Internal);
-
-	// first, destroy the main control
-	if (c->mainControl != NULL) {
-		// we have to do this before we can destroy controls
-		uiControlSetHasParent(c->mainControl, 0);
-		uiControlSetOSContainer(c->mainControl, NULL);
-		uiControlDestroy(c->mainControl);
-		c->mainControl = NULL;
-	}
-	// now we can mark the parent as ready to be destroyed
-	c->canDestroy = TRUE;
-	// finally, destroy the parent
-	g_object_unref(G_OBJECT(c));
-	// and free ourselves
-	uiFree(cc);
-}
-
-static uintptr_t parentHandle(uiOSContainer *cc)
-{
-	uipOSContainer *c = uipOSContainer(cc->Internal);
-
-	return (uintptr_t) c;
-}
-
-static void parentSetMainControl(uiOSContainer *cc, uiControl *mainControl)
-{
-	uipOSContainer *c = uipOSContainer(cc->Internal);
-
-	if (c->mainControl != NULL) {
-		uiControlSetHasParent(c->mainControl, 0);
-		uiControlSetOSContainer(c->mainControl, NULL);
-	}
-	c->mainControl = mainControl;
-	if (c->mainControl != NULL) {
-		uiControlSetHasParent(c->mainControl, 1);
-		uiControlSetOSContainer(c->mainControl, cc);
-	}
-}
-
-static void parentSetMargins(uiOSContainer *cc, intmax_t left, intmax_t top, intmax_t right, intmax_t bottom)
-{
-	uipOSContainer *c = uipOSContainer(cc->Internal);
-
-	c->marginLeft = left;
-	c->marginTop = top;
-	c->marginRight = right;
-	c->marginBottom = bottom;
-}
-
-static void parentUpdate(uiOSContainer *cc)
-{
-	uipOSContainer *c = uipOSContainer(cc->Internal);
-
-	gtk_widget_queue_resize(GTK_WIDGET(c));
-}
-
-uiOSContainer *uiNewOSContainer(uintptr_t osParent)
-{
-	uiOSContainer *c;
-
-	c = uiNew(uiOSContainer);
-	c->Internal = g_object_new(uipOSContainerType, NULL);
-	c->Destroy = parentDestroy;
-	c->Handle = parentHandle;
-	c->SetMainControl = parentSetMainControl;
-	c->SetMargins = parentSetMargins;
-	c->Update = parentUpdate;
-	gtk_container_add(GTK_CONTAINER(osParent), GTK_WIDGET(c->Internal));
-	// make it visible by default
-	gtk_widget_show_all(GTK_WIDGET(c->Internal));
-	// hold a reference to it to keep it alive
-	g_object_ref(G_OBJECT(c->Internal));
-	return c;
-}