# Custom `<Marker>` children are invisible on iOS with the New Architecture (icon view stays 0×0)

Start by reproducing the issue with React Native 0.86.2 and Fabric on iOS, then trace the marker view path around RNMapsGoogleMarkerView and its registration in RCTThirdPartyComponentsProvider. Compare custom and bare markers on both providers; done means marker icon views receive non-zero frames and render, with regression coverage for the reported cases.

Summary

On iOS with Fabric, a <Marker> whose icon is a custom child view never appears.
The marker is created and is attached to the map — its icon view simply has a
frame of {0, 0, 0, 0}, and Google Maps draws a zero-sized icon view as nothing.

Android is unaffected. <Polyline> and the map itself render correctly, which is
what makes this look like a data or coordinate problem at first.

Reproducible sample code

<MapView provider={PROVIDER_GOOGLE} initialRegion={region} style={{flex: 1}}>
  {mosques.map(m => (
    <Marker key={m.id} coordinate={{latitude: m.lat, longitude: m.lng}}>
      <View style={{alignItems: 'center'}}>
        <View style={{width: 34, height: 34, borderRadius: 17, borderWidth: 2.5}} />
        <View style={{width: 2.5, height: 9}} />
      </View>
    </Marker>
  ))}
</MapView>

Steps to reproduce

<MapView provider={PROVIDER_GOOGLE} initialRegion={region} style={{flex: 1}}>
{mosques.map(m => (
<Marker key={m.id} coordinate={{latitude: m.lat, longitude: m.lng}}>
<View style={{alignItems: 'center'}}>
<View style={{width: 34, height: 34, borderRadius: 17, borderWidth: 2.5}} />
<View style={{width: 2.5, height: 9}} />


))}

Expected result

the custom pins appear.

Actual result

nothing appears. The map, its POIs, and any <Polyline> render fine.

React Native Maps Version

1.29.0

What platforms are you seeing the problem on?

iOS (Apple Maps), iOS (Google Maps)

React Native Version

0.86.2

What version of Expo are you using?

Not using Expo

Device(s)

Iphone 17 pro max

Additional information

Each of these was tested on a real build, and none of them is the cause:

• Not the custom children — a bare <Marker coordinate title /> with no children
  is also invisible.
• Not the provider — reproduces with PROVIDER_GOOGLE and with Apple Maps.
• Not tracksViewChanges — forcing it permanently true changes nothing.
• Not mount timing — holding markers back until after onMapReady changes nothing.
• Not component registration — RNMapsGoogleMarkerView is in the app's
  RCTThirdPartyComponentsProvider, and the real implementation is what compiled
  (2.2 MB object file defining the class; PlaceHolderGoogleMarkerView.o is empty,
  so HAVE_GOOGLE_MAPS is correctly set).
• Not data — a <Polyline> drawn through the very same marker coordinates renders.