Cannot create a react native library

I’ve been creating a react native component library since a month now, and I think it’s ready to be posted as a package on npm. So I pushed it on github, I npm publish, everything’s fine.

To publish it, I replaced my index.ts:

// index.ts
import createRComps from 'Base.tsx';

export default createRComps; // That's the only object I need to export because it calls the others from itself

I also tried to use create-react-native-library on another copy of this repo, which didn’t get any more success.

Now, I create another react native project to test my new library : I install my library with npm i react-native-ready-comps, add some of my lib’s code in it :

export default function App() {
  const RComps = createRComps();  // my lib's main function

  return (
    <RComps.Title bold>Hello world !</RComps.Title>    // one of my lib's components
  );
}

But when I launch it with metro (npx react-native run-android && npx react-native start), I get this error :

 ERROR  TypeError: Cannot read property 'createNode' of null, js engine: hermes
 ERROR  Invariant Violation: Failed to call into JavaScript module method AppRegistry.runApplication(). Module has not been registered as callable. Registered callable JavaScript modules (n = 10): Systrace, JSTimers, HeapCapture, SamplingProfiler, RCTLog, RCTDeviceEventEmitter, RCTNativeAppEventEmitter, GlobalPerformanceLogger, JSDevSupportModule, HMRClient.
        A frequent cause of the error is that the application entry file path is incorrect. This can also happen when the JS bundle is corrupt or there is an early initialization error when loading React Native., js engine: hermes
 ERROR  Invariant Violation: Failed to call into JavaScript module method AppRegistry.runApplication(). Module has not been registered as callable. Registered callable JavaScript modules (n = 10): Systrace, JSTimers, HeapCapture, SamplingProfiler, RCTLog, RCTDeviceEventEmitter, RCTNativeAppEventEmitter, GlobalPerformanceLogger, JSDevSupportModule, HMRClient.
        A frequent cause of the error is that the application entry file path is incorrect. This can also happen when the JS bundle is corrupt or there is an early initialization error when loading React Native., js engine: hermes

I know it comes from my lib, but I didn’t encoutered this problem when I was working on it. Maybe did I miss something when publishing it ?

Can you please explain me what I did wrong ? And if you have resources on how to export a react native component library, I’dd be glad if you shared them ! Everything I found on Google/Stack couldn’t help me.

Thanks a lot !

PS : here is the repository of my library, if you want to see the code. As soon as it’s a project problem, I cannot create a minimal reproducible example…