Hiring a Mongoose.js developer can significantly streamline your data management. They are skilled in using this Object Data Modeling (ODM) library that provides a robust solution for managing relationships between data, providing schema validation, and translating between objects in code and the representation of those objects in MongoDB. Their expertise can help in structuring your application's data efficiently, making your applications more flexible and scalable. Moreover, Mongoose.js developers can help to improve the performance of your MongoDB database operations, ensuring your apps run smoothly and efficiently.