if (process.env.NODE_ORACLEDB_DRIVER_MODE === 'thick') {

  // Thick mode requires Oracle Client or Oracle Instant Client libraries.
  // On Windows and macOS Intel you can specify the directory containing the
  // libraries at runtime or before Node.js starts.  On other platforms (where
  // Oracle libraries are available) the system library search path must always
  // include the Oracle library path before Node.js starts.  If the search path
  // is not correct, you will get a DPI-1047 error.  See the node-oracledb
  // installation documentation.
  let clientOpts = {};
  if (process.platform === 'win32') {                                   // Windows
    clientOpts = { libDir: 'C:\\oracle\\instantclient_19_17' };
  } else if (process.platform === 'darwin' && process.arch === 'x64') { // macOS Intel
    clientOpts = { libDir: process.env.HOME + '/Downloads/instantclient_19_8' };
  }
  oracledb.initOracleClient(clientOpts);  // enable node-oracledb Thick mode
}