diff --git a/serve.go b/serve.go
index 96f157c..2dcf77f 100644
--- a/serve.go
+++ b/serve.go
@@ -36,7 +36,7 @@ func Serve(handler http.Handler) func() {
 	cb := js.FuncOf(func(_ js.Value, args []js.Value) interface{} {
 		jsReq := whutil.Request{args[0]}
 
-		var res = whutil.NewPromise(func(resolve whutil.PromiseResolve, reject whutil.PromiseReject) {
+		var resPromise = whutil.NewPromise(func(resolve whutil.PromiseResolve, reject whutil.PromiseReject) {
 			go func() {
 				defer func() {
 					r := recover()
@@ -62,7 +62,7 @@ func Serve(handler http.Handler) func() {
 			}()
 		})
 
-		return res
+		return resPromise
 	})
 
 	js.Global().Get("wasmhttp").Call("registerHandler", os.Getenv("WASMHTTP_HANDLER_ID"), cb)
diff --git a/sw.js b/sw.js
index 9e3891e..ebc029b 100644
--- a/sw.js
+++ b/sw.js
@@ -78,5 +78,5 @@ addEventListener('fetch', e => {
   const [, handler] = handlers.find(([path]) => pathname.startsWith(path)) || []
   if (!handler) return
 
-  e.respondWith((handler)(e.request))
+  e.respondWith(handler(e.request))
 })