diff --git a/example/main.go b/example/main.go
index 8e2a2f4..dcd7962 100644
--- a/example/main.go
+++ b/example/main.go
@@ -8,6 +8,10 @@ import (
 func main() {
 	router := gin.Default()
 
+	options := ginzip.DefaultOptions()
+	options.BrotliLevel = ""
+	options.GzipLevel = ""
+
 	ui := router.Group("/", ginzip.New(ginzip.DefaultOptions()))
 	ui.GET("/", getTestHandler("Hello World (should be compressed)"))
 
diff --git a/ginzip.go b/ginzip.go
index 965ece6..a3fa2d7 100644
--- a/ginzip.go
+++ b/ginzip.go
@@ -33,7 +33,7 @@ type intOptions struct {
 	GzipLevel      int
 	BrotliEn       bool
 	BrotliLevel    int
-	SkipExtensions map[string]bool
+	SkipExtensions []string
 }
 
 // New creates a new Ginzip middleware function.
@@ -136,7 +136,16 @@ func (b *brotliWriter) Encoding() string {
 	return "br"
 }
 
-func shouldCompress(req *http.Request, skipExtensions map[string]bool) bool {
+func containsString(s []string, e string) bool {
+	for _, a := range s {
+		if a == e {
+			return true
+		}
+	}
+	return false
+}
+
+func shouldCompress(req *http.Request, skipExtensions []string) bool {
 	// Dont compress websocket connections
 	if strings.Contains(req.Header.Get("Connection"), "Upgrade") ||
 		strings.Contains(req.Header.Get("Content-Type"), "text/event-stream") {
@@ -148,8 +157,7 @@ func shouldCompress(req *http.Request, skipExtensions map[string]bool) bool {
 		return true
 	}
 
-	_, doSkip := skipExtensions[extension]
-	return !doSkip
+	return !containsString(skipExtensions, extension)
 }
 
 func parseLevel(level string, dfault int, min int, max int) (int, bool) {
@@ -185,17 +193,12 @@ func parseOptions(options Options) intOptions {
 		brotli.DefaultCompression, brotli.BestSpeed, brotli.BestCompression,
 	)
 
-	exts := map[string]bool{}
-	for _, ext := range options.SkipExtensions {
-		exts[ext] = true
-	}
-
 	return intOptions{
 		GzipEn:         gzipEn,
 		GzipLevel:      gzipLvl,
 		BrotliEn:       brEn,
 		BrotliLevel:    brLvl,
-		SkipExtensions: exts,
+		SkipExtensions: options.SkipExtensions,
 	}
 }