Design Thread-Safe Tagging and Bookstore Systems

Q: Design Thread-Safe Tagging and Bookstore Systems

This question evaluates concurrent object-oriented design and large-scale systems architecture skills, covering thread-safety for document–tag relationships, many-to-many data modeling, consistency during deletes, API and storage choices, and scalability concerns for an online bookstore; it is categorized as System Design with strong OO and concurrency elements. Interviewers commonly ask this to assess reasoning about concurrency hazards, maintaining data integrity and invariants, and making trade-offs in consistency, availability, and fault tolerance, with a level of abstraction that spans both conceptual architectural thinking and practical application details such as APIs, storage and inventory consistency mechanisms.

Q: How do I approach System Design interview questions?

System Design questions require understanding of core concepts and practice. PracHub provides solutions with explanations to help you master system design interviews.

Question

System Design and OO Design (Onsite)

Part 1: Thread-Safe Document–Tag Design

Design object-oriented classes for documents and tags in a multi-threaded environment. Ensure thread-safe operations for:

Creating documents and tags
Adding/removing tags on a document
Listing tags for a document and documents for a tag
Deleting a document or a tag without leaving inconsistent relationships

Assume a many-to-many relationship between documents and tags and an in-memory implementation (you may also mention how this maps to a database if helpful).

Part 2: Scalable Online Bookstore

Design a scalable online bookstore that supports:

Browsing: view/search books, list by category, view details
Purchasing: cart, checkout, payment, inventory handling, order creation

Cover high-level architecture, data storage choices, critical APIs, consistency considerations (especially inventory), and mechanisms for scaling and fault tolerance.

Design Thread-Safe Tagging and Bookstore Systems

System Design and OO Design (Onsite)

Part 1: Thread-Safe Document–Tag Design

Part 2: Scalable Online Bookstore

Solution

Comments (0)