diff --git a/SliceTricks.md b/SliceTricks.md
index 653157ad..18a57fe9 100644
--- a/SliceTricks.md
+++ b/SliceTricks.md
@@ -179,7 +179,7 @@ Useful if you want to do batch processing on large slices.
 ```go
 actions := []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
 batchSize := 3
-var batches [][]int
+batches := make([][]int, 0, (len(actions) + batchSize - 1) / batchSize)
 
 for batchSize < len(actions) {
     actions, batches = actions[batchSize:], append(batches, actions[0:batchSize:batchSize])