diff --git a/src/Kaleidoscope.cpp b/src/Kaleidoscope.cpp
index c50d7d64..3a6bbdd0 100644
--- a/src/Kaleidoscope.cpp
+++ b/src/Kaleidoscope.cpp
@@ -14,6 +14,8 @@ Kaleidoscope_::setup(void) {
 
   // A workaround, so that the compiler does not optimize this out...
   handleKeyswitchEvent(Key_NoKey, 255, 255, 0);
+
+  // Update the key cache, so we start with a non-empty state.
   Layer.updateKeyCache();
 }
 
diff --git a/src/layers.cpp b/src/layers.cpp
index 23377a3a..100d1f7c 100644
--- a/src/layers.cpp
+++ b/src/layers.cpp
@@ -106,6 +106,9 @@ void Layer_::on(uint8_t layer) {
   bitSet(LayerState, layer);
   if (layer > highestLayer)
     highestLayer = layer;
+
+  // Update the key cache, so that if anything depends on knowing the active
+  // layout, the layout will be in sync.
   updateKeyCache();
 }
 
@@ -113,6 +116,9 @@ void Layer_::off(uint8_t layer) {
   bitClear(LayerState, layer);
   if (layer == highestLayer)
     highestLayer = top();
+
+  // Update the key cache, so that if anything depends on knowing the active
+  // layout, the layout will be in sync.
   updateKeyCache();
 }