diff --git a/Makefile b/Makefile
index bdbf47c6..acc8a41f 100644
--- a/Makefile
+++ b/Makefile
@@ -39,7 +39,6 @@ build:
 		-X github.com/thoas/picfit/constants.Branch=$(branch) \
 		-X github.com/thoas/picfit/constants.Revision=$(commit) \
 		-X 'github.com/thoas/picfit/constants.BuildTime=$(now)' \
-		-X 'github.com/thoas/picfit/constants.LatestCommitMessage=$(commitMessage)' \
 		-X 'github.com/thoas/picfit/constants.Compiler=$(compiler)'" -o $(BIN_DIR)/picfit ./cmd/picfit/main.go
 	@(echo "-> picfit binary created")
 
diff --git a/README.rst b/README.rst
index f0f9744b..f98c2bc1 100644
--- a/README.rst
+++ b/README.rst
@@ -431,6 +431,7 @@ picfit currently supports the following image formats:
 - ``image/png`` with the keyword ``png``
 - ``image/gif`` with the keyword ``gif``
 - ``image/bmp`` with the keyword ``bmp``
+- ``image/webp`` with the keyword ``webp``
 
 Operations
 ==========
diff --git a/engine/backend/backend.go b/engine/backend/backend.go
index 560b4aff..fc098cd0 100644
--- a/engine/backend/backend.go
+++ b/engine/backend/backend.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/go-spectest/imaging"
 	"github.com/pkg/errors"
 	"github.com/thoas/picfit/image"
 )
@@ -16,8 +15,7 @@ var MethodNotImplementedError = errors.New("Not implemented")
 type Options struct {
 	Color    string
 	Degree   int
-	Filter   string
-	Format   imaging.Format
+	Format   image.Format
 	Height   int
 	Images   []image.ImageFile
 	Position string
diff --git a/engine/backend/goimage.go b/engine/backend/goimage.go
index dba08d9d..a6005cdc 100644
--- a/engine/backend/goimage.go
+++ b/engine/backend/goimage.go
@@ -20,6 +20,7 @@ import (
 
 	imagefile "github.com/thoas/picfit/image"
 
+	"github.com/chai2010/webp"
 	"golang.org/x/image/bmp"
 	"golang.org/x/image/tiff"
 )
@@ -88,7 +89,7 @@ func (e *GoImage) Flip(ctx context.Context, img *imagefile.ImageFile, options *O
 }
 
 func (e *GoImage) Fit(ctx context.Context, img *imagefile.ImageFile, options *Options) ([]byte, error) {
-	if options.Format == imaging.GIF {
+	if options.Format == imagefile.GIF {
 		content, err := e.transformGIF(img, options, imaging.Thumbnail)
 		if err != nil {
 			return nil, err
@@ -105,6 +106,7 @@ func (e *GoImage) Fit(ctx context.Context, img *imagefile.ImageFile, options *Op
 	return e.transform(image, options, imaging.Fit)
 }
 
+
 func (e *GoImage) Effect(ctx context.Context, img *imagefile.ImageFile, options *Options) ([]byte, error) {
 	image, err := e.source(img)
 	if err != nil {
@@ -122,7 +124,7 @@ func (e *GoImage) Effect(ctx context.Context, img *imagefile.ImageFile, options
 	return nil, MethodNotImplementedError
 }
 
-func (e *GoImage) toBytes(img image.Image, format imaging.Format, quality int) ([]byte, error) {
+func (e *GoImage) toBytes(img image.Image, format imagefile.Format, quality int) ([]byte, error) {
 	var buf bytes.Buffer
 
 	if err := encode(&buf, img, format, quality); err != nil {
@@ -182,7 +184,7 @@ func (e *GoImage) transformGIF(img *imagefile.ImageFile, options *Options, trans
 }
 
 func (e *GoImage) resize(img *imagefile.ImageFile, options *Options, trans transformation) ([]byte, error) {
-	if options.Format == imaging.GIF {
+	if options.Format == imagefile.GIF {
 		content, err := e.transformGIF(img, options, trans)
 		if err != nil {
 			return nil, err
@@ -200,6 +202,10 @@ func (e *GoImage) resize(img *imagefile.ImageFile, options *Options, trans trans
 }
 
 func (e *GoImage) transform(img image.Image, options *Options, trans transformation) ([]byte, error) {
+	if options.Height == 0 && options.Width == 0 {
+		return e.toBytes(img, options.Format, options.Quality)
+	}
+
 	return e.toBytes(scale(img, options, trans), options.Format, options.Quality)
 }
 
@@ -238,10 +244,10 @@ func imageToPaletted(img image.Image) *image.Paletted {
 	return pm
 }
 
-func encode(w io.Writer, img image.Image, format imaging.Format, quality int) error {
+func encode(w io.Writer, img image.Image, format imagefile.Format, quality int) error {
 	var err error
 	switch format {
-	case imaging.JPEG:
+	case imagefile.JPEG:
 		var rgba *image.RGBA
 		if nrgba, ok := img.(*image.NRGBA); ok {
 			if nrgba.Opaque() {
@@ -258,14 +264,16 @@ func encode(w io.Writer, img image.Image, format imaging.Format, quality int) er
 			err = jpeg.Encode(w, img, &jpeg.Options{Quality: quality})
 		}
 
-	case imaging.PNG:
+	case imagefile.PNG:
 		err = png.Encode(w, img)
-	case imaging.GIF:
+	case imagefile.GIF:
 		err = gif.Encode(w, img, &gif.Options{NumColors: 256})
-	case imaging.TIFF:
+	case imagefile.TIFF:
 		err = tiff.Encode(w, img, &tiff.Options{Compression: tiff.Deflate, Predictor: true})
-	case imaging.BMP:
+	case imagefile.BMP:
 		err = bmp.Encode(w, img)
+	case imagefile.WEBP:
+		err = webp.Encode(w, img, &webp.Options{Quality: float32(quality)})
 	default:
 		err = imaging.ErrUnsupportedFormat
 	}
diff --git a/engine/backend/goimage_flat.go b/engine/backend/goimage_flat.go
index ed4821e2..1e1c5b19 100644
--- a/engine/backend/goimage_flat.go
+++ b/engine/backend/goimage_flat.go
@@ -27,7 +27,7 @@ func (e *GoImage) Flat(ctx context.Context, backgroundFile *imagefile.ImageFile,
 		}
 	}
 
-	if options.Format == imaging.GIF {
+	if options.Format == imagefile.GIF {
 		g, err := gif.DecodeAll(bytes.NewReader(backgroundFile.Source))
 		if err != nil {
 			return nil, err
diff --git a/engine/constants.go b/engine/constants.go
index d99acbe3..58b3e88d 100644
--- a/engine/constants.go
+++ b/engine/constants.go
@@ -15,5 +15,6 @@ var (
 		"image/gif",
 		"image/jpeg",
 		"image/png",
+		"image/webp",
 	}
 )
diff --git a/go.mod b/go.mod
index c761c2b0..d386468a 100644
--- a/go.mod
+++ b/go.mod
@@ -32,6 +32,7 @@ require (
 )
 
 require (
+	github.com/chai2010/webp v1.1.1
 	github.com/google/uuid v1.3.0
 	github.com/prometheus/client_golang v1.14.0
 	golang.org/x/sync v0.7.0
diff --git a/go.sum b/go.sum
index f75fcd24..273e791a 100644
--- a/go.sum
+++ b/go.sum
@@ -78,6 +78,8 @@ github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XL
 github.com/cespare/xxhash/v2 v2.1.2/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
 github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/chai2010/webp v1.1.1 h1:jTRmEccAJ4MGrhFOrPMpNGIJ/eybIgwKpcACsrTEapk=
+github.com/chai2010/webp v1.1.1/go.mod h1:0XVwvZWdjjdxpUEIf7b9g9VkHFnInUSYujwqTLEuldU=
 github.com/chenzhuoyu/base64x v0.0.0-20211019084208-fb5309c8db06/go.mod h1:DH46F32mSOjUmXrMHnKwZdA8wcEefY7UVqBKYGjpdQY=
 github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311/go.mod h1:b583jCggY9gE99b6G5LEC39OIiVsWj+R97kbl5odCEk=
 github.com/chenzhuoyu/base64x v0.0.0-20230717121745-296ad89f973d h1:77cEq6EriyTZ0g/qfRdp61a3Uu/AWrgIq2s0ClJV1g0=
diff --git a/image/formats.go b/image/formats.go
new file mode 100644
index 00000000..d5831ee1
--- /dev/null
+++ b/image/formats.go
@@ -0,0 +1,13 @@
+package image
+
+type Format int
+
+// Image file formats.
+const (
+	JPEG Format = iota
+	PNG
+	GIF
+	TIFF
+	BMP
+	WEBP
+)
diff --git a/parameters.go b/parameters.go
index a15911e0..2a1988fb 100644
--- a/parameters.go
+++ b/parameters.go
@@ -7,7 +7,6 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/go-spectest/imaging"
 	"github.com/pkg/errors"
 	"github.com/ulule/gostorages"
 
@@ -25,12 +24,14 @@ const (
 	defaultWidth   = 0
 )
 
-var formats = map[string]imaging.Format{
-	"bmp":  imaging.BMP,
-	"gif":  imaging.GIF,
-	"jpeg": imaging.JPEG,
-	"jpg":  imaging.JPEG,
-	"png":  imaging.PNG,
+var formats = map[string]image.Format{
+	"bmp":  image.BMP,
+	"gif":  image.GIF,
+	"jpeg": image.JPEG,
+	"jpg":  image.JPEG,
+	"png":  image.PNG,
+	"tiff": image.TIFF,
+	"webp": image.WEBP,
 }
 
 type Parameters struct {