diff --git a/app.go b/app.go
index 694aaf38..810839c6 100644
--- a/app.go
+++ b/app.go
@@ -383,7 +383,7 @@ func New(config ...Config) *App {
 	return app
 }
 
-// Mount attaches another app instance as a subrouter along a routing path.
+// Mount attaches another app instance as a sub-router along a routing path.
 // It's very useful to split up a large API as many independent routers and
 // compose them as a single service using Mount.
 func (app *App) Mount(prefix string, fiber *App) Router {
@@ -663,7 +663,7 @@ func (app *App) Test(req *http.Request, msTimeout ...int) (resp *http.Response,
 
 type disableLogger struct{}
 
-func (dl *disableLogger) Printf(format string, args ...interface{}) {
+func (dl *disableLogger) Printf(_ string, _ ...interface{}) {
 	// fmt.Println(fmt.Sprintf(format, args...))
 }
 
@@ -917,6 +917,5 @@ func (app *App) startupMessage(addr string, tls bool, pids string) {
 		out = colorable.NewNonColorable(os.Stdout)
 	}
 
-	fmt.Fprintln(out, output)
-
+	_, _ = fmt.Fprintln(out, output)
 }
diff --git a/ctx.go b/ctx.go
index f8cc2a11..0791acbc 100644
--- a/ctx.go
+++ b/ctx.go
@@ -946,7 +946,7 @@ func (c *Ctx) SendFile(file string, compress ...bool) error {
 	})
 
 	// Keep original path for mutable params
-	c.pathOriginal = utils.SafeString(c.pathOriginal)
+	c.pathOriginal = utils.CopyString(c.pathOriginal)
 	// Disable compression
 	if len(compress) <= 0 || !compress[0] {
 		// https://github.com/valyala/fasthttp/blob/master/fs.go#L46
@@ -1098,7 +1098,7 @@ func (c *Ctx) WriteString(s string) (int, error) {
 // XHR returns a Boolean property, that is true, if the request's X-Requested-With header field is XMLHttpRequest,
 // indicating that the request was issued by a client library (such as jQuery).
 func (c *Ctx) XHR() bool {
-	return utils.EqualsFold(utils.UnsafeBytes(c.Get(HeaderXRequestedWith)), []byte("xmlhttprequest"))
+	return utils.EqualFoldBytes(utils.UnsafeBytes(c.Get(HeaderXRequestedWith)), []byte("xmlhttprequest"))
 }
 
 // prettifyPath ...
diff --git a/group.go b/group.go
index a3b10e4a..6c1b13fd 100644
--- a/group.go
+++ b/group.go
@@ -15,7 +15,7 @@ type Group struct {
 	prefix string
 }
 
-// Mount attaches another app instance as a subrouter along a routing path.
+// Mount attaches another app instance as a sub-router along a routing path.
 // It's very useful to split up a large API as many independent routers and
 // compose them as a single service using Mount.
 func (grp *Group) Mount(prefix string, fiber *App) Router {
diff --git a/helpers.go b/helpers.go
index 8c53cbf4..f4612e35 100644
--- a/helpers.go
+++ b/helpers.go
@@ -364,9 +364,9 @@ func (c *testConn) Close() error                { return nil }
 
 func (c *testConn) LocalAddr() net.Addr                { return testAddr("local-addr") }
 func (c *testConn) RemoteAddr() net.Addr               { return testAddr("remote-addr") }
-func (c *testConn) SetDeadline(t time.Time) error      { return nil }
-func (c *testConn) SetReadDeadline(t time.Time) error  { return nil }
-func (c *testConn) SetWriteDeadline(t time.Time) error { return nil }
+func (c *testConn) SetDeadline(_ time.Time) error      { return nil }
+func (c *testConn) SetReadDeadline(_ time.Time) error  { return nil }
+func (c *testConn) SetWriteDeadline(_ time.Time) error { return nil }
 
 // getString converts byte slice to a string without memory allocation.
 var getString = utils.UnsafeString