metro.config.js

// metro.config.js
const path = require('path');
const {getDefaultConfig, mergeConfig} = require('@react-native/metro-config');

// Absolute path to your local library
const rnBGGeo = path.resolve(
  __dirname,
  '../../' // <--
);

// Helper to escape path in RegExp for blockList
const esc = p => p.replace(/[/\\]/g, '[\\/\\\\]');

const config = {
  watchFolders: [rnBGGeo],

  resolver: {
    // Prefer the app's copies of these to avoid duplicates from the linked lib
    extraNodeModules: {
      react: path.resolve(__dirname, 'node_modules/react'),
      'react-native': path.resolve(__dirname, 'node_modules/react-native'),
    },

    // Keep Metro from crawling the lib's nested RN (if any)
    blockList: [
      new RegExp(`${esc(rnBGGeo)}${esc('/node_modules/react-native/')}.+`),
    ],

    // Newer Metro supports this (helps with symlinks)
    unstable_enableSymlinks: true,
  },
};

module.exports = mergeConfig(getDefaultConfig(__dirname), config);