diff --git a/ebitenutil/internal/assets/assets.go b/ebitenutil/internal/assets/assets.go
index d2158a7c0..e96cbd545 100644
--- a/ebitenutil/internal/assets/assets.go
+++ b/ebitenutil/internal/assets/assets.go
@@ -23,7 +23,7 @@ import (
 const FileNameText = "text.png"
 
 //go:generate go-bindata -nocompress -pkg=assets text.png
-//go:generate gofmt -w .
+//go:generate gofmt -s -w .
 
 const (
 	TextImageWidth      = 192
diff --git a/ebitenutil/internal/assets/bindata.go b/ebitenutil/internal/assets/bindata.go
index 15192271a..8629eb579 100644
--- a/ebitenutil/internal/assets/bindata.go
+++ b/ebitenutil/internal/assets/bindata.go
@@ -143,7 +143,7 @@ type _bintree_t struct {
 }
 
 var _bintree = &_bintree_t{nil, map[string]*_bintree_t{
-	"text.png": &_bintree_t{text_png, map[string]*_bintree_t{}},
+	"text.png": {text_png, map[string]*_bintree_t{}},
 }}
 
 // Restore an asset under the given directory
diff --git a/examples/common/internal/assets/assets.go b/examples/common/internal/assets/assets.go
index 082800056..65ca42548 100644
--- a/examples/common/internal/assets/assets.go
+++ b/examples/common/internal/assets/assets.go
@@ -18,4 +18,4 @@ package assets
 // Use -ignore as a blacklist instead.
 
 //go:generate go-bindata -nocompress -pkg=assets -ignore=\.md$ images
-//go:generate gofmt -w .
+//go:generate gofmt -s -w .
diff --git a/examples/common/internal/assets/bindata.go b/examples/common/internal/assets/bindata.go
index 62d589656..fe23b49f3 100644
--- a/examples/common/internal/assets/bindata.go
+++ b/examples/common/internal/assets/bindata.go
@@ -197,11 +197,11 @@ type _bintree_t struct {
 }
 
 var _bintree = &_bintree_t{nil, map[string]*_bintree_t{
-	"images": &_bintree_t{nil, map[string]*_bintree_t{
-		"arcadefont.png": &_bintree_t{images_arcadefont_png, map[string]*_bintree_t{}},
-		"ebiten.png":     &_bintree_t{images_ebiten_png, map[string]*_bintree_t{}},
-		"fiveyears.jpg":  &_bintree_t{images_fiveyears_jpg, map[string]*_bintree_t{}},
-		"gophers.jpg":    &_bintree_t{images_gophers_jpg, map[string]*_bintree_t{}},
+	"images": {nil, map[string]*_bintree_t{
+		"arcadefont.png": {images_arcadefont_png, map[string]*_bintree_t{}},
+		"ebiten.png":     {images_ebiten_png, map[string]*_bintree_t{}},
+		"fiveyears.jpg":  {images_fiveyears_jpg, map[string]*_bintree_t{}},
+		"gophers.jpg":    {images_gophers_jpg, map[string]*_bintree_t{}},
 	}},
 }}
 
diff --git a/examples/generate.go b/examples/generate.go
index a392de694..d4bef74f6 100644
--- a/examples/generate.go
+++ b/examples/generate.go
@@ -13,6 +13,6 @@
 // limitations under the License.
 
 //go:generate go run keyboard/keyboard/gen.go
-//go:generate gofmt -w .
+//go:generate gofmt -s -w .
 
 package example
diff --git a/examples/pcm/main.go b/examples/pcm/main.go
index d4496004e..cae738dde 100644
--- a/examples/pcm/main.go
+++ b/examples/pcm/main.go
@@ -88,7 +88,7 @@ func toBytes(l, r []int16) []byte {
 		panic("len(l) must equal to len(r)")
 	}
 	b := make([]byte, len(l)*4)
-	for i, _ := range l {
+	for i := range l {
 		b[4*i] = byte(l[i])
 		b[4*i+1] = byte(l[i] >> 8)
 		b[4*i+2] = byte(r[i])
diff --git a/examples/piano/main.go b/examples/piano/main.go
index c5cf5b367..d5f31181f 100644
--- a/examples/piano/main.go
+++ b/examples/piano/main.go
@@ -71,7 +71,7 @@ func toBytes(l, r []int16) []byte {
 		panic("len(l) must equal to len(r)")
 	}
 	b := make([]byte, len(l)*4)
-	for i, _ := range l {
+	for i := range l {
 		b[4*i] = byte(l[i])
 		b[4*i+1] = byte(l[i] >> 8)
 		b[4*i+2] = byte(r[i])
diff --git a/examples/sprites/main.go b/examples/sprites/main.go
index 44917fb54..b4661d74a 100644
--- a/examples/sprites/main.go
+++ b/examples/sprites/main.go
@@ -142,7 +142,7 @@ func main() {
 		log.Fatal(err)
 	}
 	ebitenImageWidth, ebitenImageHeight = ebitenImage.Size()
-	for i, _ := range sprites.sprites {
+	for i := range sprites.sprites {
 		w, h := ebitenImage.Size()
 		x, y := rand.Intn(screenWidth-w), rand.Intn(screenHeight-h)
 		vx, vy := 2*rand.Intn(2)-1, 2*rand.Intn(2)-1
diff --git a/examples/windowsize/main.go b/examples/windowsize/main.go
index 68faa1171..0d20d4d70 100644
--- a/examples/windowsize/main.go
+++ b/examples/windowsize/main.go
@@ -42,7 +42,7 @@ var (
 )
 
 func update(screen *ebiten.Image) error {
-	for key, _ := range keyStates {
+	for key := range keyStates {
 		if !ebiten.IsKeyPressed(key) {
 			keyStates[key] = 0
 			continue
diff --git a/generate.go b/generate.go
index 956aec78a..2dd343790 100644
--- a/generate.go
+++ b/generate.go
@@ -15,4 +15,4 @@
 package ebiten
 
 //go:generate go run genkeys.go
-//go:generate gofmt -w .
+//go:generate gofmt -s -w .