diff --git a/src/userid.cc b/src/userid.cc
index 37888ca..511944f 100644
--- a/src/userid.cc
+++ b/src/userid.cc
@@ -44,7 +44,7 @@ NAN_METHOD(GroupName)
   struct group *group = NULL;
 
   if ((info.Length() > 0) && info[0]->IsInt32()) {
-    group = getgrgid(info[0]->Int32Value());
+    group = getgrgid(info[0]->Int32Value(Nan::GetCurrentContext()).FromJust());
   } else {
     return Nan::ThrowError("you must supply the gid");
   }
@@ -72,7 +72,7 @@ NAN_METHOD(Gids)
     return Nan::ThrowError("you must supply the groupname");
   }
 
-  String::Utf8Value utfname(info[0]->ToString());
+  v8::String::Utf8Value utfname(info.GetIsolate(), info[0]);
 #ifdef __APPLE__
   groups = new int[ngroups];   // malloc(ngroups * sizeof(gid_t));
 #else // ifdef __APPLE__
@@ -115,7 +115,7 @@ NAN_METHOD(Gid)
   struct group *group = NULL;
 
   if ((info.Length() > 0) && info[0]->IsString()) {
-    String::Utf8Value utfname(info[0]->ToString());
+    v8::String::Utf8Value utfname(info.GetIsolate(), info[0]);
     group = getgrnam(*utfname);
   } else {
     return Nan::ThrowError("you must supply the groupname");
@@ -134,7 +134,7 @@ NAN_METHOD(UserName)
   struct passwd *user = NULL;
 
   if ((info.Length() > 0) && info[0]->IsInt32()) {
-    user = getpwuid(info[0]->Int32Value());
+    user = getpwuid(info[0]->Int32Value(Nan::GetCurrentContext()).FromJust());
   } else {
     return Nan::ThrowError("you must supply the uid");
   }
@@ -152,7 +152,7 @@ NAN_METHOD(Uid)
   struct passwd *user = NULL;
 
   if ((info.Length() > 0) && info[0]->IsString()) {
-    String::Utf8Value utfname(info[0]->ToString());
+    v8::String::Utf8Value utfname(info.GetIsolate(), info[0]);
     user = getpwnam(*utfname);
   } else {
     return Nan::ThrowError("you must supply the username");