diff --git a/deps/swisseph/swehel.c b/deps/swisseph/swehel.c
index 59039f8..c69ba89 100644
--- a/deps/swisseph/swehel.c
+++ b/deps/swisseph/swehel.c
@@ -228,7 +228,7 @@ static double OpticFactor(double Bback, double kX, double *dobs, double JDNDaysU
   double OpticDia = dobs[4];
   double OpticTrans = dobs[5];
   AS_BOOL is_scotopic = FALSE;
-  JDNDaysUT = JDNDaysUT; /* currently not used, statement prevents compiler warning */
+  //JDNDaysUT = JDNDaysUT; /* currently not used, statement prevents compiler warning */
   SNi = SN;
   if (SNi <= 0.00000001) SNi = 0.00000001;
   /* 23 jaar as standard from Garstang*/
@@ -553,7 +553,7 @@ static double SunRA(double JDNDaysUT, int32 helflag, char *serr)
   double dut;
   static TLS double tjdlast;
   static TLS double ralast;
-  helflag = helflag; /* statement prevents compiler warning */
+  //helflag = helflag; /* statement prevents compiler warning */
   *serr = '\0';
   if (JDNDaysUT == tjdlast)
     return ralast;
@@ -1265,7 +1265,7 @@ static double Bday(double AltO, double AziO, double AltS, double AziS, double su
 static double Bcity(double Value, double Press)
 {
   double Bcity = Value;
-  Press = Press; /* unused; statement prevents compiler warning */
+  //Press = Press; /* unused; statement prevents compiler warning */
   Bcity = mymax(Bcity, 0);
   return Bcity;
 }
diff --git a/deps/swisseph/sweph.c b/deps/swisseph/sweph.c
index 159ef44..e2da85e 100644
--- a/deps/swisseph/sweph.c
+++ b/deps/swisseph/sweph.c
@@ -6524,7 +6524,7 @@ static int32 search_star_in_list(char *sstar, struct fixed_star *stardata, char
   } else if (!is_bayer && (sp = strchr(sstar, '%')) != NULL) {
     stardatabegp = &(swed.fixed_stars[swed.n_fixstars_real]);
     ndata = swed.n_fixstars_named;
-    if (sp - sstar != strlen(sstar) - 1) {
+    if (sp - sstar != (unsigned)(strlen(sstar) - 1)) {
       if (serr != NULL)
 	sprintf(serr, "error, swe_fixstar(): invalid search string %s", sstar);
       return ERR;
diff --git a/deps/swisseph/swephlib.c b/deps/swisseph/swephlib.c
index 8005a5e..2f254c4 100644
--- a/deps/swisseph/swephlib.c
+++ b/deps/swisseph/swephlib.c
@@ -789,7 +789,7 @@ static void owen_pre_matrix(double tjd, double *rp, int iflag)
     oma  += (k[i] * owen_oma_coef[icof][i]);
     chia += (k[i] * owen_chia_coef[icof][i]);
   }
-  if (iflag & (SEFLG_JPLHOR || SEFLG_JPLHOR_APPROX)) {
+  if (iflag & (SEFLG_JPLHOR | SEFLG_JPLHOR_APPROX)) {
     /* 
      * In comparison with JPL Horizons we have an almost constant offset
      * almost constant offset in ecl. longitude of about -0.000019 deg. 
diff --git a/package.json b/package.json
index 8deee3b..87c752c 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "author": "mivion",
   "name": "swisseph",
   "description": "Swiss Ephemeris binding for node.js",
-  "version": "0.5.8",
+  "version": "0.5.9",
   "homepage": "http://github.com/mivion/swisseph",
   "repository": {
     "url": "http://github.com/mivion/swisseph.git"
@@ -15,9 +15,9 @@
     "astronomy"
   ],
   "dependencies": {
+    "merge": "^1.2.x",
     "nan": "^2.1.x",
-    "node-gyp": "3.0.x",
-    "merge": "^1.2.x"
+    "node-gyp": "^3.8.0"
   },
   "devDependencies": {},
   "optionalDependencies": {},
diff --git a/src/date.cc b/src/date.cc
index 3532e6d..9f537bc 100644
--- a/src/date.cc
+++ b/src/date.cc
@@ -22,7 +22,7 @@ NAN_METHOD(node_swe_date_conversion) {
 		!info [1]->IsNumber () ||
 		!info [2]->IsNumber () ||
 		!info [3]->IsNumber () ||
-		(!info [4]->IsString () && info [4]->ToString ()->Length () > 0)
+		(!info [4]->IsString () && info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())->Length () > 0)
 	) {
 		Nan::ThrowTypeError ("Wrong type of arguments");
 	};
@@ -33,11 +33,11 @@ NAN_METHOD(node_swe_date_conversion) {
 	Local <Object> result = Nan::New<Object> ();
 
 	rflag = ::swe_date_conversion (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		info [3]->NumberValue (),
-		(* String::Utf8Value (info [4]->ToString ())) [0],
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(* String::Utf8Value (Isolate::GetCurrent(), info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0],
 		&tjd
 	);
 
@@ -74,11 +74,11 @@ NAN_METHOD(node_swe_julday) {
 	};
 
 	Local <Number> result = Nan::New<Number> (::swe_julday (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		info [3]->NumberValue (),
-		(int)info [4]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	));
 
     HandleCallback (info, result);
@@ -115,8 +115,8 @@ NAN_METHOD(node_swe_revjul) {
 	Local <Object> result = Nan::New<Object> ();
 
 	::swe_revjul (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&year, &month, &day, &hour
 	);
 
@@ -164,13 +164,13 @@ NAN_METHOD(node_swe_utc_to_jd) {
 	Local <Object> result = Nan::New<Object> ();
 
 	rflag = ::swe_utc_to_jd (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
-		info [5]->NumberValue (),
-		(int)info [6]->NumberValue (),
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		tjd, serr
 	);
 
@@ -217,8 +217,8 @@ NAN_METHOD(node_swe_jdet_to_utc) {
 	Local <Object> result = Nan::New<Object> ();
 
 	::swe_jdet_to_utc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&year, &month, &day, &hour, &minute, &second
 	);
 
@@ -265,8 +265,8 @@ NAN_METHOD(node_swe_jdut1_to_utc) {
 	Local <Object> result = Nan::New<Object> ();
 
 	::swe_jdut1_to_utc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&year, &month, &day, &hour, &minute, &second
 	);
 
@@ -318,13 +318,13 @@ NAN_METHOD(node_swe_utc_time_zone) {
 	Local <Object> result = Nan::New<Object> ();
 
 	::swe_utc_time_zone (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
-		info [5]->NumberValue (),
-		info [6]->NumberValue (),
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&year, &month, &day, &hour, &minute, &second
 	);
 
diff --git a/src/eclipse.cc b/src/eclipse.cc
index 433df35..ba94179 100644
--- a/src/eclipse.cc
+++ b/src/eclipse.cc
@@ -39,21 +39,21 @@ NAN_METHOD(node_swe_gauquelin_sector) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
-	geopos [0] = info [5]->NumberValue ();
-	geopos [1] = info [6]->NumberValue ();
-	geopos [2] = info [7]->NumberValue ();
+	geopos [0] = info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [7]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_gauquelin_sector (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos,
-		info [8]->NumberValue (),
-		info [9]->NumberValue (),
+		info [8]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [9]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&dgsect, serr
 	);
 
@@ -111,8 +111,8 @@ NAN_METHOD(node_swe_sol_eclipse_where) {
 	long rflag;
 
 	rflag = ::swe_sol_eclipse_where (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, attr, serr
 	);
 
@@ -181,13 +181,13 @@ NAN_METHOD(node_swe_lun_occult_where) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_lun_occult_where (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, attr, serr
 	);
 
@@ -254,13 +254,13 @@ NAN_METHOD(node_swe_sol_eclipse_how) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_sol_eclipse_how (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, attr, serr
 	);
 
@@ -335,15 +335,15 @@ NAN_METHOD(node_swe_sol_eclipse_when_loc) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_sol_eclipse_when_loc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, tret, attr,
-		(int)info [5]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -427,19 +427,19 @@ NAN_METHOD(node_swe_lun_occult_when_loc) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
-	geopos [0] = info [4]->NumberValue ();
-	geopos [1] = info [5]->NumberValue ();
-	geopos [2] = info [6]->NumberValue ();
+	geopos [0] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_lun_occult_when_loc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, tret, attr,
-		(int)info [7]->NumberValue (),
+		(int)info [7]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -509,11 +509,11 @@ NAN_METHOD(node_swe_sol_eclipse_when_glob) {
 	long rflag;
 
 	rflag = ::swe_sol_eclipse_when_glob (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		tret,
-		(int)info [3]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -577,16 +577,16 @@ NAN_METHOD(node_swe_lun_occult_when_glob) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_lun_occult_when_glob (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		tret,
-		(int)info [5]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -650,13 +650,13 @@ NAN_METHOD(node_swe_lun_eclipse_how) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_lun_eclipse_how (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, attr, serr
 	);
 
@@ -717,11 +717,11 @@ NAN_METHOD(node_swe_lun_eclipse_when) {
 	long rflag;
 
 	rflag = ::swe_lun_eclipse_when (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		tret,
-		(int)info [3]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -793,15 +793,15 @@ NAN_METHOD(node_swe_lun_eclipse_when_loc) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_lun_eclipse_when_loc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, tret, attr,
-		(int)info [5]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		serr
 	);
 
@@ -866,9 +866,9 @@ NAN_METHOD(node_swe_pheno) {
 	long rflag;
 
 	rflag = ::swe_pheno (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		attr, serr
 	);
 
@@ -921,9 +921,9 @@ NAN_METHOD(node_swe_pheno_ut) {
 	long rflag;
 
 	rflag = ::swe_pheno_ut (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		attr, serr
 	);
 
@@ -970,10 +970,10 @@ NAN_METHOD(node_swe_refrac) {
 	double refraction;
 
 	refraction = ::swe_refrac (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue (),
-		(int)info [3]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -1016,12 +1016,12 @@ NAN_METHOD(node_swe_refrac_extended) {
 	double dret [4];
 
 	refraction = ::swe_refrac_extended (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue (),
-		info [3]->NumberValue (),
-		info [4]->NumberValue (),
-		(int)info [5]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dret
 	);
 
@@ -1056,7 +1056,7 @@ NAN_METHOD(node_swe_set_lapse_rate) {
 	};
 
 	::swe_set_lapse_rate (
-        info [0]->NumberValue ()
+        info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -1100,20 +1100,20 @@ NAN_METHOD(node_swe_azalt) {
 	double xin [3] = {0};
 	double xaz [3] = {0};
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	xin [0] = info [7]->NumberValue ();
-	xin [1] = info [8]->NumberValue ();
-	xin [2] = info [9]->NumberValue ();
+	xin [0] = info [7]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xin [1] = info [8]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xin [2] = info [9]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	::swe_azalt (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos,
-		info [5]->NumberValue (),
-		info [6]->NumberValue (),
+		info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		xin, xaz
 	);
 
@@ -1158,16 +1158,16 @@ NAN_METHOD(node_swe_azalt_rev) {
 	double xin [3] = {0};
 	double xout [3] = {0};
 
-	geopos [0] = info [2]->NumberValue ();
-	geopos [1] = info [3]->NumberValue ();
-	geopos [2] = info [4]->NumberValue ();
+	geopos [0] = info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	xin [0] = info [5]->NumberValue ();
-	xin [1] = info [6]->NumberValue ();
+	xin [0] = info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xin [1] = info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	::swe_azalt_rev (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos, xin, xout
 	);
 
@@ -1217,21 +1217,21 @@ NAN_METHOD(node_swe_rise_trans) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
-	geopos [0] = info [5]->NumberValue ();
-	geopos [1] = info [6]->NumberValue ();
-	geopos [2] = info [7]->NumberValue ();
+	geopos [0] = info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [7]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_rise_trans (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos,
-		info [8]->NumberValue (),
-		info [9]->NumberValue (),
+		info [8]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [9]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&tret, serr
 	);
 
@@ -1290,22 +1290,22 @@ NAN_METHOD(node_swe_rise_trans_true_hor) {
 	char serr [AS_MAXCH];
 	long rflag;
 
-	::strcpy (star, * String::Utf8Value (info [2]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
-	geopos [0] = info [5]->NumberValue ();
-	geopos [1] = info [6]->NumberValue ();
-	geopos [2] = info [7]->NumberValue ();
+	geopos [0] = info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [1] = info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	geopos [2] = info [7]->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	rflag = ::swe_rise_trans_true_hor (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		star,
-		(int)info [3]->NumberValue (),
-		(int)info [4]->NumberValue (),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		geopos,
-		info [8]->NumberValue (),
-		info [9]->NumberValue (),
-		info [10]->NumberValue (),
+		info [8]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [9]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [10]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&tret, serr
 	);
 
@@ -1389,10 +1389,10 @@ NAN_METHOD(node_swe_nod_aps) {
 	long rflag;
 
 	rflag = ::swe_nod_aps (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		(int)info [3]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		xnasc, xndsc, xperi, xaphe, serr
 	);
 
@@ -1401,7 +1401,7 @@ NAN_METHOD(node_swe_nod_aps) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			Local <Object> ascending = Nan::New<Object> ();
 			ascending->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), 		Nan::New<Number> (xnasc [0]));
 			ascending->Set (Nan::New<String> ("declination").ToLocalChecked(), 		Nan::New<Number> (xnasc [1]));
@@ -1438,7 +1438,7 @@ NAN_METHOD(node_swe_nod_aps) {
 			aphelion->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(),		Nan::New<Number> (xaphe [5]));
 			result->Set (Nan::New<String> ("aphelion").ToLocalChecked(), aphelion);
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				Local <Object> ascending = Nan::New<Object> ();
 				ascending->Set (Nan::New<String> ("x").ToLocalChecked(), 		Nan::New<Number> (xnasc [0]));
 				ascending->Set (Nan::New<String> ("y").ToLocalChecked(), 		Nan::New<Number> (xnasc [1]));
@@ -1579,10 +1579,10 @@ NAN_METHOD(node_swe_nod_aps_ut) {
 	long rflag;
 
 	rflag = ::swe_nod_aps_ut (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
-		(int)info [3]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		xnasc, xndsc, xperi, xaphe, serr
 	);
 
@@ -1591,7 +1591,7 @@ NAN_METHOD(node_swe_nod_aps_ut) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			Local <Object> ascending = Nan::New<Object> ();
 			ascending->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), 		Nan::New<Number> (xnasc [0]));
 			ascending->Set (Nan::New<String> ("declination").ToLocalChecked(), 		Nan::New<Number> (xnasc [1]));
@@ -1628,7 +1628,7 @@ NAN_METHOD(node_swe_nod_aps_ut) {
 			aphelion->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(),		Nan::New<Number> (xaphe [5]));
 			result->Set (Nan::New<String> ("aphelion").ToLocalChecked(), aphelion);
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				Local <Object> ascending = Nan::New<Object> ();
 				ascending->Set (Nan::New<String> ("x").ToLocalChecked(), 		Nan::New<Number> (xnasc [0]));
 				ascending->Set (Nan::New<String> ("y").ToLocalChecked(), 		Nan::New<Number> (xnasc [1]));
diff --git a/src/hel.cc b/src/hel.cc
index 2ca28eb..45ecc75 100644
--- a/src/hel.cc
+++ b/src/hel.cc
@@ -40,29 +40,29 @@ NAN_METHOD(node_swe_heliacal_ut) {
 	char name [AS_MAXCH];
 	long rflag;
 
-	dgeo [0] = info [1]->ToObject ()->Get (0)->NumberValue ();
-	dgeo [1] = info [1]->ToObject ()->Get (1)->NumberValue ();
-	dgeo [2] = info [1]->ToObject ()->Get (2)->NumberValue ();
+	dgeo [0] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [1] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [2] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	datm [0] = info [2]->ToObject ()->Get (0)->NumberValue ();
-	datm [1] = info [2]->ToObject ()->Get (1)->NumberValue ();
-	datm [2] = info [2]->ToObject ()->Get (2)->NumberValue ();
-	datm [3] = info [2]->ToObject ()->Get (3)->NumberValue ();
+	datm [0] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [1] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [2] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [3] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	dobs [0] = info [3]->ToObject ()->Get (0)->NumberValue ();
-	dobs [1] = info [3]->ToObject ()->Get (1)->NumberValue ();
-	dobs [2] = info [3]->ToObject ()->Get (2)->NumberValue ();
-	dobs [3] = info [3]->ToObject ()->Get (3)->NumberValue ();
-	dobs [4] = info [3]->ToObject ()->Get (4)->NumberValue ();
-	dobs [5] = info [3]->ToObject ()->Get (5)->NumberValue ();
+	dobs [0] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [1] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [2] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [3] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [4] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (4)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [5] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (5)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	::strcpy (name, *String::Utf8Value (info [4]->ToString ()));
+	::strcpy (name, *String::Utf8Value (Isolate::GetCurrent(), info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_heliacal_ut (
-		info [0]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dgeo, datm, dobs, name,
-		(int)info [5]->NumberValue (),
-		(int)info [6]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dret, serr
 	);
 
@@ -147,29 +147,29 @@ NAN_METHOD(node_swe_heliacal_pheno_ut) {
 	char name [AS_MAXCH];
 	long rflag;
 
-	dgeo [0] = info [1]->ToObject ()->Get (0)->NumberValue ();
-	dgeo [1] = info [1]->ToObject ()->Get (1)->NumberValue ();
-	dgeo [2] = info [1]->ToObject ()->Get (2)->NumberValue ();
+	dgeo [0] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [1] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [2] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	datm [0] = info [2]->ToObject ()->Get (0)->NumberValue ();
-	datm [1] = info [2]->ToObject ()->Get (1)->NumberValue ();
-	datm [2] = info [2]->ToObject ()->Get (2)->NumberValue ();
-	datm [3] = info [2]->ToObject ()->Get (3)->NumberValue ();
+	datm [0] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [1] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [2] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [3] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	dobs [0] = info [3]->ToObject ()->Get (0)->NumberValue ();
-	dobs [1] = info [3]->ToObject ()->Get (1)->NumberValue ();
-	dobs [2] = info [3]->ToObject ()->Get (2)->NumberValue ();
-	dobs [3] = info [3]->ToObject ()->Get (3)->NumberValue ();
-	dobs [4] = info [3]->ToObject ()->Get (4)->NumberValue ();
-	dobs [5] = info [3]->ToObject ()->Get (5)->NumberValue ();
+	dobs [0] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [1] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [2] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [3] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [4] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (4)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [5] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (5)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	::strcpy (name, *String::Utf8Value (info [4]->ToString ()));
+	::strcpy (name, *String::Utf8Value (Isolate::GetCurrent(), info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_heliacal_ut (
-		info [0]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dgeo, datm, dobs, name,
-		(int)info [5]->NumberValue (),
-		(int)info [6]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [6]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		darr, serr
 	);
 
@@ -257,28 +257,28 @@ NAN_METHOD(node_swe_vis_limit_mag) {
 	char name [AS_MAXCH];
 	long rflag;
 
-	dgeo [0] = info [1]->ToObject ()->Get (0)->NumberValue ();
-	dgeo [1] = info [1]->ToObject ()->Get (1)->NumberValue ();
-	dgeo [2] = info [1]->ToObject ()->Get (2)->NumberValue ();
+	dgeo [0] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [1] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dgeo [2] = info [1]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	datm [0] = info [2]->ToObject ()->Get (0)->NumberValue ();
-	datm [1] = info [2]->ToObject ()->Get (1)->NumberValue ();
-	datm [2] = info [2]->ToObject ()->Get (2)->NumberValue ();
-	datm [3] = info [2]->ToObject ()->Get (3)->NumberValue ();
+	datm [0] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [1] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [2] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	datm [3] = info [2]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	dobs [0] = info [3]->ToObject ()->Get (0)->NumberValue ();
-	dobs [1] = info [3]->ToObject ()->Get (1)->NumberValue ();
-	dobs [2] = info [3]->ToObject ()->Get (2)->NumberValue ();
-	dobs [3] = info [3]->ToObject ()->Get (3)->NumberValue ();
-	dobs [4] = info [3]->ToObject ()->Get (4)->NumberValue ();
-	dobs [5] = info [3]->ToObject ()->Get (5)->NumberValue ();
+	dobs [0] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [1] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [2] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [3] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (3)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [4] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (4)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	dobs [5] = info [3]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (5)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
-	::strcpy (name, *String::Utf8Value (info [4]->ToString ()));
+	::strcpy (name, *String::Utf8Value (Isolate::GetCurrent(), info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_vis_limit_mag (
-		info [0]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dgeo, datm, dobs, name,
-		(int)info [5]->NumberValue (),
+		(int)info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		dret, serr
 	);
 
diff --git a/src/house.cc b/src/house.cc
index d1a3e67..fddee58 100644
--- a/src/house.cc
+++ b/src/house.cc
@@ -43,7 +43,7 @@ NAN_METHOD(node_swe_houses) {
 	Local <Object> result = Nan::New<Object> ();
 	Local <Array> house = Nan::New<Array> ();
 
-	hsys = (* String::Utf8Value (info [3]->ToString ())) [0];
+	hsys = (* String::Utf8Value (Isolate::GetCurrent(), info [3]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0];
 	
 	if (hsys == 'G') {
 		cuspsCount = 36;
@@ -52,9 +52,9 @@ NAN_METHOD(node_swe_houses) {
 	}
 
 	rflag = ::swe_houses (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		hsys,
 		cusps, ascmc
 	);
@@ -123,7 +123,7 @@ NAN_METHOD(node_swe_houses_ex) {
 	Local <Object> result = Nan::New<Object> ();
 	Local <Array> house = Nan::New<Array> ();
 
-	hsys = (* String::Utf8Value (info [4]->ToString ())) [0];
+	hsys = (* String::Utf8Value (Isolate::GetCurrent(), info [4]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0];
 	
 	if (hsys == 'G') {
 		cuspsCount = 36;
@@ -132,10 +132,10 @@ NAN_METHOD(node_swe_houses_ex) {
 	}
 
 	rflag = ::swe_houses_ex (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		info [2]->NumberValue (),
-		info [3]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [3]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		hsys,
 		cusps, ascmc
 	);
@@ -203,7 +203,7 @@ NAN_METHOD(node_swe_houses_armc) {
 	Local <Object> result = Nan::New<Object> ();
 	Local <Array> house = Nan::New<Array> ();
 
-	hsys = (* String::Utf8Value (info [3]->ToString ())) [0];
+	hsys = (* String::Utf8Value (Isolate::GetCurrent(), info [3]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0];
 	
 	if (hsys == 'G') {
 		cuspsCount = 36;
@@ -212,9 +212,9 @@ NAN_METHOD(node_swe_houses_armc) {
 	}
 	
 	rflag = ::swe_houses_armc (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		hsys,
 		cusps, ascmc
 	);
@@ -267,17 +267,17 @@ NAN_METHOD(node_swe_houses_pos) {
 		Nan::ThrowTypeError ("Wrong type of arguments");
 	};
 
-	double xpin [2] = {info [4]->NumberValue (), info [5]->NumberValue ()};
+	double xpin [2] = {info [4]->NumberValue (Nan::GetCurrentContext()).ToChecked(), info [5]->NumberValue (Nan::GetCurrentContext()).ToChecked()};
 	char serr [AS_MAXCH];
 	double rflag;
 
 	Local <Object> result = Nan::New<Object> ();
 
 	rflag = ::swe_house_pos (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue (),
-		(* String::Utf8Value (info [3]->ToString ())) [0],
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(* String::Utf8Value (Isolate::GetCurrent(), info [3]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0],
 		xpin, serr
 	);
 
diff --git a/src/pos.cc b/src/pos.cc
index 2706371..5e70694 100644
--- a/src/pos.cc
+++ b/src/pos.cc
@@ -54,9 +54,9 @@ NAN_METHOD(node_swe_calc_ut) {
 	long rflag;
 
 	rflag = ::swe_calc_ut (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -65,7 +65,7 @@ NAN_METHOD(node_swe_calc_ut) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
 			result->Set (Nan::New<String> ("distance").ToLocalChecked(), Nan::New<Number> (x [2]));
@@ -74,7 +74,7 @@ NAN_METHOD(node_swe_calc_ut) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
 				result->Set (Nan::New<String> ("z").ToLocalChecked(), Nan::New<Number> (x [2]));
@@ -130,9 +130,9 @@ NAN_METHOD(node_swe_calc) {
 	long rflag;
 
 	rflag = ::swe_calc (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -141,7 +141,7 @@ NAN_METHOD(node_swe_calc) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
 			result->Set (Nan::New<String> ("distance").ToLocalChecked(), Nan::New<Number> (x [2]));
@@ -150,7 +150,7 @@ NAN_METHOD(node_swe_calc) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
 				result->Set (Nan::New<String> ("z").ToLocalChecked(), Nan::New<Number> (x [2]));
@@ -207,12 +207,12 @@ NAN_METHOD(node_swe_fixstar) {
 	long rflag = 0;
 	char star [AS_MAXCH];
 
-	::strcpy (star, * String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar (
 		star,
-		info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -221,7 +221,7 @@ NAN_METHOD(node_swe_fixstar) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -231,7 +231,7 @@ NAN_METHOD(node_swe_fixstar) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -290,12 +290,12 @@ NAN_METHOD(node_swe_fixstar_ut) {
 	long rflag = 0;
 	char star [AS_MAXCH];
 
-	::strcpy (star, *String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, *String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar_ut (
 		star,
-		info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -304,7 +304,7 @@ NAN_METHOD(node_swe_fixstar_ut) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -314,7 +314,7 @@ NAN_METHOD(node_swe_fixstar_ut) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -365,7 +365,7 @@ NAN_METHOD(node_swe_fixstar_mag) {
 	long rflag;
 	double magnitude;
 
-	::strcpy (star, *String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, *String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar_mag (star, &magnitude, serr);
 
@@ -417,12 +417,12 @@ NAN_METHOD(node_swe_fixstar2) {
 	long rflag = 0;
 	char star [AS_MAXCH];
 
-	::strcpy (star, * String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, * String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar2 (
 		star,
-		info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -431,7 +431,7 @@ NAN_METHOD(node_swe_fixstar2) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -441,7 +441,7 @@ NAN_METHOD(node_swe_fixstar2) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -500,12 +500,12 @@ NAN_METHOD(node_swe_fixstar2_ut) {
 	long rflag = 0;
 	char star [AS_MAXCH];
 
-	::strcpy (star, *String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, *String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar2_ut (
 		star,
-		info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		x, serr
 	);
 
@@ -514,7 +514,7 @@ NAN_METHOD(node_swe_fixstar2_ut) {
 	if (rflag < 0) {
 		result->Set (Nan::New<String> ("error").ToLocalChecked(), Nan::New<String> (serr).ToLocalChecked());
 	} else 
-		if ((int)info [2]->NumberValue () & SEFLG_EQUATORIAL) {
+		if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_EQUATORIAL) {
 			result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 			result->Set (Nan::New<String> ("rectAscension").ToLocalChecked(), Nan::New<Number> (x [0]));
 			result->Set (Nan::New<String> ("declination").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -524,7 +524,7 @@ NAN_METHOD(node_swe_fixstar2_ut) {
 			result->Set (Nan::New<String> ("distanceSpeed").ToLocalChecked(), Nan::New<Number> (x [5]));
 			result->Set (Nan::New<String> ("rflag").ToLocalChecked(), Nan::New<Number> (rflag));
 		} else
-			if ((int)info [2]->NumberValue () & SEFLG_XYZ) {
+			if ((int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked() & SEFLG_XYZ) {
 				result->Set (Nan::New<String> ("name").ToLocalChecked(), Nan::New<String> (star).ToLocalChecked());
 				result->Set (Nan::New<String> ("x").ToLocalChecked(), Nan::New<Number> (x [0]));
 				result->Set (Nan::New<String> ("y").ToLocalChecked(), Nan::New<Number> (x [1]));
@@ -575,7 +575,7 @@ NAN_METHOD(node_swe_fixstar2_mag) {
 	long rflag;
 	double magnitude;
 
-	::strcpy (star, *String::Utf8Value (info [0]->ToString ()));
+	::strcpy (star, *String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>())));
 
 	rflag = ::swe_fixstar2_mag (star, &magnitude, serr);
 
@@ -625,10 +625,10 @@ NAN_METHOD(node_swe_set_ephe_path) {
 	};
 
 	::swe_set_ephe_path (
-		*String::Utf8Value (info [0]->ToString ())
+		*String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))
 	);
 
-	Local <Object> result = info [0]->ToObject ();
+	Local <Object> result = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>());
 
     HandleCallback (info, result);
     info.GetReturnValue().Set (result);
@@ -653,10 +653,10 @@ NAN_METHOD(node_swe_set_jpl_file) {
 	};
 
 	::swe_set_jpl_file (
-		*String::Utf8Value (info [0]->ToString ())
+		*String::Utf8Value (Isolate::GetCurrent(), info [0]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))
 	);
 
-	Local <Object> result = info [0]->ToObject ();
+	Local <Object> result = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>());
 
     HandleCallback (info, result);
     info.GetReturnValue().Set (result);
@@ -684,7 +684,7 @@ NAN_METHOD(node_swe_get_planet_name) {
 
 	char name [AS_MAXCH] = {0};
 
-	::swe_get_planet_name ((int)info [0]->NumberValue (), name);
+	::swe_get_planet_name ((int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(), name);
 
 	Local <Object> result = Nan::New<Object> ();
 
@@ -715,9 +715,9 @@ NAN_METHOD(node_swe_set_topo) {
 	};
 
 	::swe_set_topo (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
     HandleCallback (info, Nan::Undefined());
@@ -745,9 +745,9 @@ NAN_METHOD(node_swe_set_sid_mode) {
 	};
 
 	::swe_set_sid_mode (
-		(int)info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
     HandleCallback (info, Nan::Undefined());
@@ -775,7 +775,7 @@ NAN_METHOD(node_swe_get_ayanamsa) {
 	double val;
 
 	val = ::swe_get_ayanamsa (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Number> result = Nan::New<Number> (val);
@@ -805,7 +805,7 @@ NAN_METHOD(node_swe_get_ayanamsa_ut) {
 	double val;
 
 	val = ::swe_get_ayanamsa_ut (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Number> result = Nan::New<Number> (val);
@@ -842,8 +842,8 @@ NAN_METHOD(node_swe_get_ayanamsa_ex) {
 	long val;
 
 	val = ::swe_get_ayanamsa_ex (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		daya, serr
 	);
 
@@ -886,8 +886,8 @@ NAN_METHOD(node_swe_get_ayanamsa_ex_ut) {
 	long val;
 
 	val = ::swe_get_ayanamsa_ex_ut (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		daya, serr
 	);
 
@@ -923,7 +923,7 @@ NAN_METHOD(node_swe_get_ayanamsa_name) {
 	const char * val;
 
 	val = ::swe_get_ayanamsa_name (
-		(int)info [0]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <String> result = Nan::New<String> (val).ToLocalChecked();
diff --git a/src/swisseph.h b/src/swisseph.h
index c78604c..9c6fab5 100644
--- a/src/swisseph.h
+++ b/src/swisseph.h
@@ -1,7 +1,7 @@
 #ifndef __swisseph_swisseph_h__
 #define __swisseph_swisseph_h__
 
-#pragma warning (disable : 4251)
+//#pragma warning (disable : 4251)
 
 #include <node.h>
 #include <nan.h>
diff --git a/src/util.cc b/src/util.cc
index f907b2a..e3ce101 100644
--- a/src/util.cc
+++ b/src/util.cc
@@ -25,7 +25,7 @@ NAN_METHOD(node_swe_deltat) {
 	double deltat;
 
 	deltat = ::swe_deltat (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -62,7 +62,7 @@ NAN_METHOD(node_swe_time_equ) {
 	long rflag;
 
 	rflag = ::swe_time_equ (
-		info [0]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&te, serr
 	);
 
@@ -103,9 +103,9 @@ NAN_METHOD(node_swe_sidtime0) {
 	double st;
 
 	st = ::swe_sidtime0 (
-		info [0]->NumberValue (),
-		info [1]->NumberValue (),
-		info [2]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -139,7 +139,7 @@ NAN_METHOD(node_swe_sidtime) {
 	double st;
 
 	st = ::swe_sidtime (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -176,13 +176,13 @@ NAN_METHOD(node_swe_cotrans) {
 	double xpn [3] = {0};
 	double xpo [3] = {0};
 
-	xpo [0] = info [0]->ToObject ()->Get (0)->NumberValue ();
-	xpo [1] = info [0]->ToObject ()->Get (1)->NumberValue ();
-	xpo [2] = info [0]->ToObject ()->Get (2)->NumberValue ();
+	xpo [0] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xpo [1] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xpo [2] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	::swe_cotrans (
 		xpo, xpn,
-        info [1]->NumberValue ()
+        info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -221,13 +221,13 @@ NAN_METHOD(node_swe_cotrans_sp) {
 	double xpn [3] = {0};
 	double xpo [3] = {0};
 
-	xpo [0] = info [0]->ToObject ()->Get (0)->NumberValue ();
-	xpo [1] = info [0]->ToObject ()->Get (1)->NumberValue ();
-	xpo [2] = info [0]->ToObject ()->Get (2)->NumberValue ();
+	xpo [0] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (0)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xpo [1] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (1)->NumberValue (Nan::GetCurrentContext()).ToChecked();
+	xpo [2] = info [0]->ToObject (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::Object>())->Get (2)->NumberValue (Nan::GetCurrentContext()).ToChecked();
 
 	::swe_cotrans_sp (
 		xpo, xpn,
-        info [1]->NumberValue ()
+        info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -282,7 +282,7 @@ NAN_METHOD(node_swe_set_tid_acc) {
 	};
 
 	::swe_set_tid_acc (
-        info [0]->NumberValue ()
+        info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -314,7 +314,7 @@ NAN_METHOD(node_swe_degnorm) {
 	double x360;
 
 	x360 = ::swe_degnorm (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -348,7 +348,7 @@ NAN_METHOD(node_swe_radnorm) {
 	double x2Pi;
 
 	x2Pi = ::swe_radnorm (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -383,8 +383,8 @@ NAN_METHOD(node_swe_rad_midp) {
 	double xMid2Pi;
 
 	xMid2Pi = ::swe_rad_midp (
-		info [0]->NumberValue (),
-		info [1]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -419,8 +419,8 @@ NAN_METHOD(node_swe_deg_midp) {
 	double xMid360;
 
 	xMid360 = ::swe_deg_midp (
-		info [0]->NumberValue (),
-		info [1]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -463,8 +463,8 @@ NAN_METHOD(node_swe_split_deg) {
 	int isgn;
 
 	::swe_split_deg (
-		info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		&ideg, &imin, &isec, &dsecfr, &isgn
 	);
 
@@ -503,7 +503,7 @@ NAN_METHOD(node_swe_csnorm) {
 	int centisec360;
 
 	centisec360 = ::swe_csnorm (
-		(int)info [0]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -538,8 +538,8 @@ NAN_METHOD(node_swe_difcsn ) {
 	int centisecDiff;
 
 	centisecDiff = ::swe_difcsn (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -574,8 +574,8 @@ NAN_METHOD(node_swe_difdegn ) {
 	double degreeDiff;
 
 	degreeDiff = ::swe_difdegn (
-		info [0]->NumberValue (),
-		info [1]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -610,8 +610,8 @@ NAN_METHOD(node_swe_difcs2n) {
 	int centisecDistance180;
 
 	centisecDistance180 = ::swe_difcs2n (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -646,8 +646,8 @@ NAN_METHOD(node_swe_difdeg2n) {
 	double degreeDistance180;
 
 	degreeDistance180 = ::swe_difdeg2n (
-		info [0]->NumberValue (),
-		info [1]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -682,8 +682,8 @@ NAN_METHOD(node_swe_difrad2n) {
 	double degreeDistancePi;
 
 	degreeDistancePi = ::swe_difrad2n (
-		info [0]->NumberValue (),
-		info [1]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -717,7 +717,7 @@ NAN_METHOD(node_swe_csroundsec) {
 	int centisecRound;
 
 	centisecRound = ::swe_csroundsec (
-		(int)info [0]->NumberValue ()
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -751,7 +751,7 @@ NAN_METHOD(node_swe_d2l) {
 	int xRound;
 
 	xRound = ::swe_d2l (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -785,7 +785,7 @@ NAN_METHOD(node_swe_day_of_week) {
 	int dayOfWeek;
 
 	dayOfWeek = ::swe_day_of_week (
-		info [0]->NumberValue ()
+		info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked()
 	);
 
 	Local <Object> result = Nan::New<Object> ();
@@ -821,9 +821,9 @@ NAN_METHOD(node_swe_cs2timestr) {
 	char timeString [AS_MAXCH] = {0};
 
 	::swe_cs2timestr (
-		(int)info [0]->NumberValue (),
-		(int)info [1]->NumberValue (),
-		(int)info [2]->NumberValue (),
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [1]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(int)info [2]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		timeString
 	);
 
@@ -860,9 +860,9 @@ NAN_METHOD(node_swe_cs2lonlatstr) {
 	char lonlatString [AS_MAXCH] = {0};
 
 	::swe_cs2lonlatstr (
-		(int)info [0]->NumberValue (),
-		(* String::Utf8Value (info [1]->ToString ())) [0],
-		(* String::Utf8Value (info [2]->ToString ())) [0],
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
+		(* String::Utf8Value (Isolate::GetCurrent(), info [1]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0],
+		(* String::Utf8Value (Isolate::GetCurrent(), info [2]->ToString (Nan::GetCurrentContext()).FromMaybe(v8::Local<v8::String>()))) [0],
 		lonlatString
 	);
 
@@ -897,7 +897,7 @@ NAN_METHOD(node_swe_cs2degstr) {
 	char degreeString [AS_MAXCH] = {0};
 
 	::swe_cs2degstr (
-		(int)info [0]->NumberValue (),
+		(int)info [0]->NumberValue (Nan::GetCurrentContext()).ToChecked(),
 		degreeString
 	);