diff --git a/src/demo/sliding.c b/src/demo/sliding.c
index 3757c3ad8..798a16c1f 100644
--- a/src/demo/sliding.c
+++ b/src/demo/sliding.c
@@ -7,6 +7,19 @@
 #define CHUNKS_VERT 8
 #define CHUNKS_HORZ 16
 
+static int
+fill_chunk(struct ncplane* n, int idx){
+  char buf[4];
+  int maxy, maxx;
+  ncplane_dimyx(n, &maxy, &maxx);
+  snprintf(buf, sizeof(buf), "%03d", idx);
+  ncplane_fg_rgb8(n, 255 - (idx * 4), idx * 4, 255 - (idx * 4));
+  if(ncplane_putstr(n, buf) <= 0){
+    return -1;
+  }
+  return 0;
+}
+
 // break whatever's on the screen into panels and shift them around like a
 // sliding puzzle. FIXME once we have copying, anyway. until then, just use
 // background colors.
@@ -38,8 +51,12 @@ int sliding_puzzle_demo(struct notcurses* nc){
       if(chunks[idx] == NULL){
         goto done;
       }
+      fill_chunk(chunks[idx], idx);
     }
   }
+  if(notcurses_render(nc)){
+    goto done;
+  }
   nanosleep(&demodelay, NULL);
   ret = 0;
 
diff --git a/src/lib/notcurses.c b/src/lib/notcurses.c
index 152ddc8d6..c90864a0d 100644
--- a/src/lib/notcurses.c
+++ b/src/lib/notcurses.c
@@ -933,16 +933,16 @@ int cell_load(ncplane* n, cell* c, const char* gcluster){
   return bytes;
 }
 
-int ncplane_putstr(ncplane* n, const char* gcluster){
+int ncplane_putstr(ncplane* n, const char* gclusters){
   int ret = 0;
   // FIXME speed up this blissfully naive solution
-  while(*gcluster){
+  while(*gclusters){
     // FIXME can we not dispense with this cell, and print directly in?
     cell c;
     memset(&c, 0, sizeof(c));
     c.channels = n->channels;
     c.attrword = n->attrword;
-    int wcs = cell_load(n, &c, gcluster);
+    int wcs = cell_load(n, &c, gclusters);
     if(wcs < 0){
       return -ret;
     }
@@ -950,7 +950,7 @@ int ncplane_putstr(ncplane* n, const char* gcluster){
       break;
     }
     ncplane_putc(n, &c);
-    gcluster += wcs;
+    gclusters += wcs;
     ret += wcs;
     if(ncplane_cursor_stuck(n)){
       break;