diff --git a/src/cache_test.go b/src/cache_test.go
index 8a2d2cf..5d9c5cc 100644
--- a/src/cache_test.go
+++ b/src/cache_test.go
@@ -4,9 +4,8 @@ import "testing"
 
 func TestChunkCache(t *testing.T) {
 	cache := NewChunkCache()
-	chunk2 := make(Chunk, chunkSize)
 	chunk1p := &Chunk{}
-	chunk2p := &chunk2
+	chunk2p := &Chunk{count: chunkSize}
 	items1 := []Result{Result{}}
 	items2 := []Result{Result{}, Result{}}
 	cache.Add(chunk1p, "foo", items1)
diff --git a/src/chunklist.go b/src/chunklist.go
index 4a4458a..599a1ad 100644
--- a/src/chunklist.go
+++ b/src/chunklist.go
@@ -3,11 +3,14 @@ package fzf
 import "sync"
 
 // Chunk is a list of Items whose size has the upper limit of chunkSize
-type Chunk []Item
+type Chunk struct {
+	items [chunkSize]Item
+	count int
+}
 
 // ItemBuilder is a closure type that builds Item object from a pointer to a
 // string and an integer
-type ItemBuilder func([]byte, int) Item
+type ItemBuilder func(*Item, []byte, int) bool
 
 // ChunkList is a list of Chunks
 type ChunkList struct {
@@ -27,17 +30,16 @@ func NewChunkList(trans ItemBuilder) *ChunkList {
 }
 
 func (c *Chunk) push(trans ItemBuilder, data []byte, index int) bool {
-	item := trans(data, index)
-	if item.Nil() {
-		return false
+	if trans(&c.items[c.count], data, index) {
+		c.count++
+		return true
 	}
-	*c = append(*c, item)
-	return true
+	return false
 }
 
 // IsFull returns true if the Chunk is full
 func (c *Chunk) IsFull() bool {
-	return len(*c) == chunkSize
+	return c.count == chunkSize
 }
 
 func (cl *ChunkList) lastChunk() *Chunk {
@@ -49,7 +51,7 @@ func CountItems(cs []*Chunk) int {
 	if len(cs) == 0 {
 		return 0
 	}
-	return chunkSize*(len(cs)-1) + len(*(cs[len(cs)-1]))
+	return chunkSize*(len(cs)-1) + cs[len(cs)-1].count
 }
 
 // Push adds the item to the list
@@ -57,8 +59,7 @@ func (cl *ChunkList) Push(data []byte) bool {
 	cl.mutex.Lock()
 
 	if len(cl.chunks) == 0 || cl.lastChunk().IsFull() {
-		newChunk := Chunk(make([]Item, 0, chunkSize))
-		cl.chunks = append(cl.chunks, &newChunk)
+		cl.chunks = append(cl.chunks, &Chunk{})
 	}
 
 	if cl.lastChunk().push(cl.trans, data, cl.count) {
diff --git a/src/chunklist_test.go b/src/chunklist_test.go
index 78468e3..c8d33a6 100644
--- a/src/chunklist_test.go
+++ b/src/chunklist_test.go
@@ -11,10 +11,10 @@ func TestChunkList(t *testing.T) {
 	// FIXME global
 	sortCriteria = []criterion{byScore, byLength}
 
-	cl := NewChunkList(func(s []byte, i int) Item {
-		chars := util.ToChars(s)
-		chars.Index = int32(i * 2)
-		return Item{text: chars}
+	cl := NewChunkList(func(item *Item, s []byte, i int) bool {
+		item.text = util.ToChars(s)
+		item.text.Index = int32(i * 2)
+		return true
 	})
 
 	// Snapshot
@@ -40,11 +40,13 @@ func TestChunkList(t *testing.T) {
 
 	// Check the content of the ChunkList
 	chunk1 := snapshot[0]
-	if len(*chunk1) != 2 {
+	if chunk1.count != 2 {
 		t.Error("Snapshot should contain only two items")
 	}
-	if (*chunk1)[0].text.ToString() != "hello" || (*chunk1)[0].Index() != 0 ||
-		(*chunk1)[1].text.ToString() != "world" || (*chunk1)[1].Index() != 2 {
+	if chunk1.items[0].text.ToString() != "hello" ||
+		chunk1.items[0].Index() != 0 ||
+		chunk1.items[1].text.ToString() != "world" ||
+		chunk1.items[1].Index() != 2 {
 		t.Error("Invalid data")
 	}
 	if chunk1.IsFull() {
@@ -67,14 +69,14 @@ func TestChunkList(t *testing.T) {
 		!snapshot[1].IsFull() || snapshot[2].IsFull() || count != chunkSize*2+2 {
 		t.Error("Expected two full chunks and one more chunk")
 	}
-	if len(*snapshot[2]) != 2 {
+	if snapshot[2].count != 2 {
 		t.Error("Unexpected number of items")
 	}
 
 	cl.Push([]byte("hello"))
 	cl.Push([]byte("world"))
 
-	lastChunkCount := len(*snapshot[len(snapshot)-1])
+	lastChunkCount := snapshot[len(snapshot)-1].count
 	if lastChunkCount != 2 {
 		t.Error("Unexpected number of items:", lastChunkCount)
 	}
diff --git a/src/core.go b/src/core.go
index 0b90a51..968d407 100644
--- a/src/core.go
+++ b/src/core.go
@@ -85,29 +85,30 @@ func Run(opts *Options, revision string) {
 	var chunkList *ChunkList
 	header := make([]string, 0, opts.HeaderLines)
 	if len(opts.WithNth) == 0 {
-		chunkList = NewChunkList(func(data []byte, index int) Item {
+		chunkList = NewChunkList(func(item *Item, data []byte, index int) bool {
 			if len(header) < opts.HeaderLines {
 				header = append(header, string(data))
 				eventBox.Set(EvtHeader, header)
-				return nilItem
+				return false
 			}
-			chars, colors := ansiProcessor(data)
-			chars.Index = int32(index)
-			return Item{text: chars, colors: colors}
+			item.text, item.colors = ansiProcessor(data)
+			item.text.Index = int32(index)
+			return true
 		})
 	} else {
-		chunkList = NewChunkList(func(data []byte, index int) Item {
+		chunkList = NewChunkList(func(item *Item, data []byte, index int) bool {
 			tokens := Tokenize(string(data), opts.Delimiter)
 			trans := Transform(tokens, opts.WithNth)
 			transformed := joinTokens(trans)
 			if len(header) < opts.HeaderLines {
 				header = append(header, transformed)
 				eventBox.Set(EvtHeader, header)
-				return nilItem
+				return false
 			}
-			trimmed, colors := ansiProcessor([]byte(transformed))
-			trimmed.Index = int32(index)
-			return Item{text: trimmed, colors: colors, origText: &data}
+			item.text, item.colors = ansiProcessor([]byte(transformed))
+			item.text.Index = int32(index)
+			item.origText = &data
+			return true
 		})
 	}
 
@@ -151,8 +152,8 @@ func Run(opts *Options, revision string) {
 			slab := util.MakeSlab(slab16Size, slab32Size)
 			reader := Reader{
 				func(runes []byte) bool {
-					item := chunkList.trans(runes, 0)
-					if !item.Nil() {
+					item := Item{}
+					if chunkList.trans(&item, runes, 0) {
 						if result, _, _ := pattern.MatchItem(&item, false, slab); result != nil {
 							opts.Printer(item.text.ToString())
 							found = true
diff --git a/src/item.go b/src/item.go
index b3879cb..cb778cb 100644
--- a/src/item.go
+++ b/src/item.go
@@ -17,11 +17,7 @@ func (item *Item) Index() int32 {
 	return item.text.Index
 }
 
-var nilItem = Item{text: util.Chars{Index: -1}}
-
-func (item *Item) Nil() bool {
-	return item.Index() < 0
-}
+var minItem = Item{text: util.Chars{Index: -1}}
 
 func (item *Item) TrimLength() uint16 {
 	return item.text.TrimLength()
diff --git a/src/merger.go b/src/merger.go
index 7d30a76..d710f2a 100644
--- a/src/merger.go
+++ b/src/merger.go
@@ -29,7 +29,7 @@ func PassMerger(chunks *[]*Chunk, tac bool) *Merger {
 		count:   0}
 
 	for _, chunk := range *mg.chunks {
-		mg.count += len(*chunk)
+		mg.count += chunk.count
 	}
 	return &mg
 }
@@ -65,7 +65,7 @@ func (mg *Merger) Get(idx int) Result {
 			idx = mg.count - idx - 1
 		}
 		chunk := (*mg.chunks)[idx/chunkSize]
-		return Result{item: &(*chunk)[idx%chunkSize]}
+		return Result{item: &chunk.items[idx%chunkSize]}
 	}
 
 	if mg.sorted {
diff --git a/src/pattern.go b/src/pattern.go
index 8de15b9..94615ad 100644
--- a/src/pattern.go
+++ b/src/pattern.go
@@ -278,8 +278,8 @@ func (p *Pattern) matchChunk(chunk *Chunk, space []Result, slab *util.Slab) []Re
 	matches := []Result{}
 
 	if space == nil {
-		for idx := range *chunk {
-			if match, _, _ := p.MatchItem(&(*chunk)[idx], false, slab); match != nil {
+		for idx := 0; idx < chunk.count; idx++ {
+			if match, _, _ := p.MatchItem(&chunk.items[idx], false, slab); match != nil {
 				matches = append(matches, *match)
 			}
 		}
diff --git a/src/pattern_test.go b/src/pattern_test.go
index 4066eb4..54d6f51 100644
--- a/src/pattern_test.go
+++ b/src/pattern_test.go
@@ -130,12 +130,11 @@ func TestOrigTextAndTransformed(t *testing.T) {
 
 	origBytes := []byte("junegunn.choi")
 	for _, extended := range []bool{false, true} {
-		chunk := Chunk{
-			Item{
-				text:        util.ToChars([]byte("junegunn")),
-				origText:    &origBytes,
-				transformed: &trans},
-		}
+		chunk := Chunk{count: 1}
+		chunk.items[0] = Item{
+			text:        util.ToChars([]byte("junegunn")),
+			origText:    &origBytes,
+			transformed: &trans}
 		pattern.extended = extended
 		matches := pattern.matchChunk(&chunk, nil, slab) // No cache
 		if !(matches[0].item.text.ToString() == "junegunn" &&
@@ -144,7 +143,7 @@ func TestOrigTextAndTransformed(t *testing.T) {
 			t.Error("Invalid match result", matches)
 		}
 
-		match, offsets, pos := pattern.MatchItem(&chunk[0], true, slab)
+		match, offsets, pos := pattern.MatchItem(&chunk.items[0], true, slab)
 		if !(match.item.text.ToString() == "junegunn" &&
 			string(*match.item.origText) == "junegunn.choi" &&
 			offsets[0][0] == 0 && offsets[0][1] == 5 &&
diff --git a/src/result.go b/src/result.go
index 2df101b..58cbafd 100644
--- a/src/result.go
+++ b/src/result.go
@@ -85,7 +85,7 @@ func (result *Result) Index() int32 {
 }
 
 func minRank() Result {
-	return Result{item: &nilItem, points: [4]uint16{math.MaxUint16, 0, 0, 0}}
+	return Result{item: &minItem, points: [4]uint16{math.MaxUint16, 0, 0, 0}}
 }
 
 func (result *Result) colorOffsets(matchOffsets []Offset, theme *tui.ColorTheme, color tui.ColorPair, attr tui.Attr, current bool) []colorOffset {