diff --git a/ios/RNGLContext.m b/ios/RNGLContext.m
index 909aac30db9295724f8e82436ed9c1e7d483ce7c..75b021b161887e6073cca23d02c8d42e8ffc80d1 100644
--- a/ios/RNGLContext.m
+++ b/ios/RNGLContext.m
@@ -49,13 +49,17 @@ RCT_EXPORT_MODULE()
 withConfig:(NSDictionary *)config
 withOnCompile:(RCTResponseSenderBlock)onCompile
 {
+  NSString *vert = [RCTConvert NSString:config[@"vert"]];
   NSString *frag = [RCTConvert NSString:config[@"frag"]];
   NSString *name = [RCTConvert NSString:config[@"name"]];
+  if (!vert) {
+    vert = fullViewportVert;
+  }
   if (!frag) {
     RCTLogError(@"Shader '%@': missing frag field", name);
     return;
   }
-  GLShader *shader = [[GLShader alloc] initWithContext:_context withName:name withVert:fullViewportVert withFrag:frag];
+  GLShader *shader = [[GLShader alloc] initWithContext:_context withName:name withVert:vert withFrag:frag];
   NSError *error;
   bool success = [shader ensureCompiles:&error];
   if (onCompile) {
@@ -112,13 +116,17 @@ NSDictionary* glTypesString (NSDictionary *types) {
 RCT_EXPORT_METHOD(addShader:(nonnull NSNumber *)id
                   withConfig:(NSDictionary *)config
                   withOnCompile:(RCTResponseSenderBlock)onCompile) {
+  NSString *vert = [RCTConvert NSString:config[@"vert"]];
   NSString *frag = [RCTConvert NSString:config[@"frag"]];
   NSString *name = [RCTConvert NSString:config[@"name"]];
+  if (!vert) {
+    vert = fullViewportVert;
+  }
   if (!frag) {
     RCTLogError(@"Shader '%@': missing frag field", name);
     return;
   }
-  GLShader *shader = [[GLShader alloc] initWithContext:_context withName:name withVert:fullViewportVert withFrag:frag];
+  GLShader *shader = [[GLShader alloc] initWithContext:_context withName:name withVert:vert withFrag:frag];
   NSError *error;
   bool success = [shader ensureCompiles:&error];
   if (onCompile) {
@@ -158,4 +166,4 @@ RCT_EXPORT_METHOD(removeShader:(nonnull NSNumber *)id) {
   return [self moduleForClass:[RNGLContext class]];
 }
 
-@end
\ No newline at end of file
+@end