diff --git a/client_test.go b/client_test.go
index d2111144d..70676e399 100644
--- a/client_test.go
+++ b/client_test.go
@@ -195,11 +195,11 @@ func TestClient_ImportInverseEnabled(t *testing.T) {
 	hldr := MustOpenHolder()
 	defer hldr.Close()
 
-	d := hldr.MustCreateIndexIfNotExists("i", pilosa.IndexOptions{})
+	idx := hldr.MustCreateIndexIfNotExists("i", pilosa.IndexOptions{})
 	frameOpts := pilosa.FrameOptions{
 		InverseEnabled: true,
 	}
-	frame, err := d.CreateFrameIfNotExists("f", frameOpts)
+	frame, err := idx.CreateFrameIfNotExists("f", frameOpts)
 	if err != nil {
 		panic(err)
 	}
diff --git a/executor.go b/executor.go
index 8c7fef54a..d1fd8b829 100644
--- a/executor.go
+++ b/executor.go
@@ -160,11 +160,11 @@ func (e *Executor) executeBitmapCall(ctx context.Context, index string, c *pql.C
 	bm, _ := other.(*Bitmap)
 	if c.Name == "Bitmap" {
 
-		d := e.Holder.Index(index)
-		if d != nil {
-			columnLabel := d.ColumnLabel()
+		idx := e.Holder.Index(index)
+		if idx != nil {
+			columnLabel := idx.ColumnLabel()
 			if columnID, ok, err := c.UintArg(columnLabel); ok && err == nil {
-				attrs, err := d.ColumnAttrStore().Attrs(columnID)
+				attrs, err := idx.ColumnAttrStore().Attrs(columnID)
 				if err != nil {
 					return nil, err
 				}
@@ -173,7 +173,7 @@ func (e *Executor) executeBitmapCall(ctx context.Context, index string, c *pql.C
 				return nil, err
 			} else {
 				frame, _ := c.Args["frame"].(string)
-				if fr := d.Frame(frame); fr != nil {
+				if fr := idx.Frame(frame); fr != nil {
 					rowLabel := fr.RowLabel()
 					rowID, _, err := c.UintArg(rowLabel)
 					if err != nil {
@@ -362,11 +362,11 @@ func (e *Executor) executeDifferenceSlice(ctx context.Context, index string, c *
 
 func (e *Executor) executeBitmapSlice(ctx context.Context, index string, c *pql.Call, slice uint64) (*Bitmap, error) {
 	// Fetch column label from index.
-	d := e.Holder.Index(index)
-	if d == nil {
+	idx := e.Holder.Index(index)
+	if idx == nil {
 		return nil, ErrIndexNotFound
 	}
-	columnLabel := d.ColumnLabel()
+	columnLabel := idx.ColumnLabel()
 
 	// Fetch frame & row label based on argument.
 	frame, _ := c.Args["frame"].(string)
@@ -548,17 +548,17 @@ func (e *Executor) executeClearBit(ctx context.Context, index string, c *pql.Cal
 	}
 
 	// Retrieve frame.
-	d := e.Holder.Index(index)
-	if d == nil {
+	idx := e.Holder.Index(index)
+	if idx == nil {
 		return false, ErrIndexNotFound
 	}
-	f := d.Frame(frame)
+	f := idx.Frame(frame)
 	if f == nil {
 		return false, ErrFrameNotFound
 	}
 
 	// Retrieve labels.
-	columnLabel := d.ColumnLabel()
+	columnLabel := idx.ColumnLabel()
 	rowLabel := f.RowLabel()
 
 	// Read fields using labels.
@@ -642,17 +642,17 @@ func (e *Executor) executeSetBit(ctx context.Context, index string, c *pql.Call,
 	}
 
 	// Retrieve frame.
-	d := e.Holder.Index(index)
-	if d == nil {
+	idx := e.Holder.Index(index)
+	if idx == nil {
 		return false, ErrIndexNotFound
 	}
-	f := d.Frame(frame)
+	f := idx.Frame(frame)
 	if f == nil {
 		return false, ErrFrameNotFound
 	}
 
 	// Retrieve labels.
-	columnLabel := d.ColumnLabel()
+	columnLabel := idx.ColumnLabel()
 	rowLabel := f.RowLabel()
 
 	// Read fields using labels.
@@ -886,8 +886,8 @@ func (e *Executor) executeBulkSetRowAttrs(ctx context.Context, index string, cal
 // executeSetColumnAttrs executes a SetColumnAttrs() call.
 func (e *Executor) executeSetColumnAttrs(ctx context.Context, index string, c *pql.Call, opt *ExecOptions) error {
 	// Retrieve index.
-	d := e.Holder.Index(index)
-	if d == nil {
+	idx := e.Holder.Index(index)
+	if idx == nil {
 		return ErrIndexNotFound
 	}
 
@@ -895,7 +895,7 @@ func (e *Executor) executeSetColumnAttrs(ctx context.Context, index string, c *p
 	id, okID, errID := c.UintArg("id")
 	if errID != nil || !okID {
 		// Retrieve columnLabel
-		columnLabel := d.columnLabel
+		columnLabel := idx.columnLabel
 		col, okCol, errCol := c.UintArg(columnLabel)
 		if errCol != nil || !okCol {
 			return fmt.Errorf("reading SetColumnAttrs() id/columnLabel errs: %v/%v found %v/%v", errID, errCol, okID, okCol)
@@ -911,7 +911,7 @@ func (e *Executor) executeSetColumnAttrs(ctx context.Context, index string, c *p
 	delete(attrs, colName)
 
 	// Set attributes.
-	if err := d.ColumnAttrStore().SetAttrs(id, attrs); err != nil {
+	if err := idx.ColumnAttrStore().SetAttrs(id, attrs); err != nil {
 		return err
 	}
 
diff --git a/handler_test.go b/handler_test.go
index fbf7041e8..d0b467f90 100644
--- a/handler_test.go
+++ b/handler_test.go
@@ -648,8 +648,8 @@ func TestHandler_Frame_AttrStore_Diff(t *testing.T) {
 	defer s.Close()
 
 	// Set attributes on the index.
-	d := hldr.MustCreateIndexIfNotExists("i", pilosa.IndexOptions{})
-	f, err := d.CreateFrameIfNotExists("meta", pilosa.FrameOptions{})
+	idx := hldr.MustCreateIndexIfNotExists("i", pilosa.IndexOptions{})
+	f, err := idx.CreateFrameIfNotExists("meta", pilosa.FrameOptions{})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -701,7 +701,7 @@ func TestHandler_Fragment_BackupRestore(t *testing.T) {
 	f0 := hldr.MustCreateFragmentIfNotExists("i", "f", pilosa.ViewStandard, 0)
 	f0.MustSetBits(100, 1, 2, 3)
 
-	// Begin backing up from slice d/f/0.
+	// Begin backing up from slice i/f/0.
 	resp, err := http.Get(s.URL + "/fragment/data?index=i&frame=f&view=standard&slice=0")
 	if err != nil {
 		t.Fatal(err)
diff --git a/holder.go b/holder.go
index 054cffe57..426817410 100644
--- a/holder.go
+++ b/holder.go
@@ -281,11 +281,11 @@ func (h *Holder) DeleteIndex(name string) error {
 
 // Frame returns the frame for an index and name.
 func (h *Holder) Frame(index, name string) *Frame {
-	d := h.Index(index)
-	if d == nil {
+	idx := h.Index(index)
+	if idx == nil {
 		return nil
 	}
-	return d.Frame(name)
+	return idx.Frame(name)
 }
 
 // View returns the view for an index, frame, and name.
@@ -423,13 +423,13 @@ func (s *HolderSyncer) SyncHolder() error {
 // syncIndex synchronizes index attributes with the rest of the cluster.
 func (s *HolderSyncer) syncIndex(index string) error {
 	// Retrieve index reference.
-	d := s.Holder.Index(index)
-	if d == nil {
+	idx := s.Holder.Index(index)
+	if idx == nil {
 		return nil
 	}
 
 	// Read block checksums.
-	blks, err := d.ColumnAttrStore().Blocks()
+	blks, err := idx.ColumnAttrStore().Blocks()
 	if err != nil {
 		return err
 	}
@@ -451,12 +451,12 @@ func (s *HolderSyncer) syncIndex(index string) error {
 		}
 
 		// Update local copy.
-		if err := d.ColumnAttrStore().SetBulkAttrs(m); err != nil {
+		if err := idx.ColumnAttrStore().SetBulkAttrs(m); err != nil {
 			return err
 		}
 
 		// Recompute blocks.
-		blks, err = d.ColumnAttrStore().Blocks()
+		blks, err = idx.ColumnAttrStore().Blocks()
 		if err != nil {
 			return err
 		}
diff --git a/holder_test.go b/holder_test.go
index 7452123b4..78c4700f8 100644
--- a/holder_test.go
+++ b/holder_test.go
@@ -150,7 +150,7 @@ func TestHolderSyncer_SyncHolder(t *testing.T) {
 		f = hldr.Fragment("i", "f0", pilosa.ViewStandard, 1)
 		a := f.Row(9).Bits()
 		if !reflect.DeepEqual(a, []uint64{SliceWidth + 5}) {
-			t.Fatalf("unexpected bits(%d/d/f0): %+v", i, a)
+			t.Fatalf("unexpected bits(%d/i/f0): %+v", i, a)
 		}
 		if a := f.Row(9).Bits(); !reflect.DeepEqual(a, []uint64{SliceWidth + 5}) {
 			t.Fatalf("unexpected bits(%d/d/f0): %+v", i, a)
@@ -199,11 +199,11 @@ func (h *Holder) Close() error {
 
 // MustCreateIndexIfNotExists returns a given index. Panic on error.
 func (h *Holder) MustCreateIndexIfNotExists(index string, opt pilosa.IndexOptions) *Index {
-	d, err := h.Holder.CreateIndexIfNotExists(index, opt)
+	idx, err := h.Holder.CreateIndexIfNotExists(index, opt)
 	if err != nil {
 		panic(err)
 	}
-	return &Index{Index: d}
+	return &Index{Index: idx}
 }
 
 // MustCreateFrameIfNotExists returns a given frame. Panic on error.
@@ -217,8 +217,8 @@ func (h *Holder) MustCreateFrameIfNotExists(index, frame string) *Frame {
 
 // MustCreateFragmentIfNotExists returns a given fragment. Panic on error.
 func (h *Holder) MustCreateFragmentIfNotExists(index, frame, view string, slice uint64) *Fragment {
-	d := h.MustCreateIndexIfNotExists(index, pilosa.IndexOptions{})
-	f, err := d.CreateFrameIfNotExists(frame, pilosa.FrameOptions{})
+	idx := h.MustCreateIndexIfNotExists(index, pilosa.IndexOptions{})
+	f, err := idx.CreateFrameIfNotExists(frame, pilosa.FrameOptions{})
 	if err != nil {
 		panic(err)
 	}
diff --git a/server.go b/server.go
index 0f178898c..6aef3dd62 100644
--- a/server.go
+++ b/server.go
@@ -240,11 +240,11 @@ func (s *Server) monitorMaxSlices() {
 func (s *Server) ReceiveMessage(pb proto.Message) error {
 	switch obj := pb.(type) {
 	case *internal.CreateSliceMessage:
-		d := s.Holder.Index(obj.Index)
-		if d == nil {
+		idx := s.Holder.Index(obj.Index)
+		if idx == nil {
 			return fmt.Errorf("Local Index not found: %s", obj.Index)
 		}
-		d.SetRemoteMaxSlice(obj.Slice)
+		idx.SetRemoteMaxSlice(obj.Slice)
 	case *internal.CreateIndexMessage:
 		opt := IndexOptions{ColumnLabel: obj.Meta.ColumnLabel}
 		_, err := s.Holder.CreateIndex(obj.Index, opt)
@@ -300,7 +300,7 @@ func (s *Server) mergeRemoteState(ns *internal.NodeState) error {
 			ColumnLabel: index.Meta.ColumnLabel,
 			TimeQuantum: TimeQuantum(index.Meta.TimeQuantum),
 		}
-		d, err := s.Holder.CreateIndexIfNotExists(index.Name, opt)
+		idx, err := s.Holder.CreateIndexIfNotExists(index.Name, opt)
 		if err != nil {
 			return err
 		}
@@ -311,7 +311,7 @@ func (s *Server) mergeRemoteState(ns *internal.NodeState) error {
 				TimeQuantum: TimeQuantum(f.Meta.TimeQuantum),
 				CacheSize:   f.Meta.CacheSize,
 			}
-			_, err := d.CreateFrameIfNotExists(f.Name, opt)
+			_, err := idx.CreateFrameIfNotExists(f.Name, opt)
 			if err != nil {
 				return err
 			}