Preparing for a low-level design interview involves understanding various concepts related to designing software systems at a detailed level. Here’s a comprehensive list of topics you should cover:
- Object-Oriented Design Principles:
- SOLID principles (Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, Dependency Inversion)
- DRY (Don’t Repeat Yourself) principle
- KISS (Keep It Simple, Stupid) principle
- YAGNI (You Aren’t Gonna Need It) principle
- Design Patterns:
- Creational patterns (e.g., Singleton, Factory, Abstract Factory)
- Structural patterns (e.g., Adapter, Composite, Decorator)
- Behavioral patterns (e.g., Observer, Strategy, Command)
- System Design Fundamentals:
- Component-based architecture
- Modular design
- Abstraction and encapsulation
- Coupling and cohesion
- Data Structures:
- Arrays, linked lists, stacks, queues
- Trees (binary trees, binary search trees, AVL trees, B-trees)
- Graphs (representations, traversal algorithms)
- Algorithms:
- Sorting algorithms (e.g., quicksort, mergesort)
- Searching algorithms (e.g., binary search)
- Graph algorithms (e.g., BFS, DFS, Dijkstra’s algorithm)
- Concurrency and Multithreading:
- Thread safety
- Synchronization mechanisms (e.g., locks, semaphores, monitors)
- Concurrent data structures
- Deadlock prevention and handling
- Database Design:
- Relational database concepts (tables, columns, primary keys, foreign keys)
- Normalization (1NF, 2NF, 3NF)
- Indexing and query optimization
- NoSQL databases and their use cases
- Caching Strategies:
- Cache coherence
- Cache eviction policies (e.g., LRU, LFU)
- Distributed caching
- Security Considerations:
- Authentication and authorization mechanisms
- Input validation and data sanitization
- Encryption and hashing techniques
- Defense against common security threats (e.g., SQL injection, XSS)
- Performance Optimization:
- Profiling and benchmarking
- Bottleneck identification
- Scalability strategies (e.g., horizontal scaling, vertical scaling)
- Load balancing and distribution strategies
- API Design:
- RESTful principles
- HTTP methods and status codes
- Versioning and backward compatibility
- Error handling and response formats
- Designing for Testability:
- Unit testing and mocking frameworks
- Integration testing strategies
- Test-driven development (TDD) principles
- Software Development Lifecycle:
- Agile methodologies (e.g., Scrum, Kanban)
- Continuous integration and deployment (CI/CD)
- Version control systems (e.g., Git)
- Code review and collaboration practices
- Real-world System Design Scenarios:
- Scalable web services (e.g., social media platforms, e-commerce sites)
- Distributed systems (e.g., messaging systems, distributed databases)
- Real-time processing systems (e.g., streaming analytics, online gaming)
- Design Trade-offs and Considerations:
- Performance vs. scalability
- Consistency vs. availability vs. partition tolerance (CAP theorem)
- Cost-effectiveness and resource utilization
Remember to practice designing systems end-to-end, considering requirements gathering, architectural decisions, component design, and trade-off analysis. Additionally, be ready to articulate your thought process and communicate effectively during the interview.