// Imperative
const fe_engineers = (engineers) => {
  const fe_engineers = [];
  for (let i = 0; i < engineers.length; i++) {
    fe_engineers[i] = `fe_${engineers[i]}`;
  }
  return fe_engineers;
}


// Declarative
const fe_engineers = (engineers) =>
  engineers.map(name => `fe_${name}`);