Do freshers need to know system design?

For freshers (entry-level software engineers), system design is typically not a major focus in interviews. Most companies don’t expect fresh graduates to have deep knowledge of large-scale system design, as these concepts are often learned through real-world experience and working on large projects. However, having a basic understanding of system design concepts can be valuable and may be tested, especially at top tech companies or in situations where you’re applying for roles that involve backend or distributed systems.

Here’s a breakdown of what freshers need to know about system design:

1. Basic System Design Concepts

a. Understanding Core Components

While you won’t be expected to design complex systems as a fresher, having an understanding of the basic components of a system will help you in both interviews and on the job. These components include:

• Clients (frontend): Mobile apps, web browsers, or devices that interact with the system.
• Backend services: APIs and services that handle business logic and data processing.
• Databases: Where the system stores data, both SQL (relational) and NoSQL (non-relational).
• Load balancers: Tools that distribute incoming traffic across multiple servers.
• Caching: Strategies for storing frequently accessed data in memory to speed up response times.

Understanding how these components fit together can help freshers answer basic questions about system interactions.

b. High-Level Knowledge of Scalability and Performance

Freshers should know basic scalability concepts, such as:

• Vertical vs. horizontal scaling: Adding more power to a single server (vertical) vs. adding more servers (horizontal).
• Caching: Using tools like Redis or Memcached to improve performance by storing frequently used data.
• Basic load balancing: Ensuring traffic is distributed evenly across servers to prevent overloading.

While you won’t be asked to design complex systems, understanding these concepts can help you explain how systems scale.

2. When Freshers Need to Know System Design

a. Big Tech Companies (FAANG)

Top tech companies, such as Google, Facebook (Meta), Amazon, and Microsoft, may ask basic system design questions even for freshers. These questions are usually simpler and focus on understanding scalability, database choices, and data flow rather than designing complex architectures.

Example: You might be asked how you would design a simple URL shortener, where you only need to explain how URLs are mapped and stored in a database, with some very basic caching concepts.

b. Startups or Backend-Focused Roles

If you’re applying for roles at startups or for positions that involve backend development, even as a fresher, the interview may touch on basic system design concepts. This is because startups often look for candidates who can contribute to both frontend and backend development in the early stages of the company.

Example: A startup may ask you how you’d design a simple message queue system, where users send messages that need to be processed by background workers.

3. Key System Design Topics Freshers Should Know

a. Basic Database Design

Freshers should know how to design a simple database schema and understand the differences between SQL and NoSQL databases:

• SQL: Use for structured, relational data that requires strong consistency (e.g., user profiles, transactions).
• NoSQL: Use for unstructured or semi-structured data and when scalability and flexibility are prioritized (e.g., large-scale document storage, user activity logs).

Example: Designing a basic e-commerce database schema with tables for users, products, and orders.

b. Data Flow and API Design

Understanding how data flows between different parts of the system is important:

• Frontend → Backend → Database: Know how user requests from the frontend are processed by the backend and how data is retrieved or updated in the database.
• APIs: Understand basic RESTful API design principles, including how services communicate with each other via HTTP methods (GET, POST, PUT, DELETE).

Example: Designing an API for a simple blogging platform, where users can create posts, comment on posts, and retrieve posts.

4. Expectations in a System Design Interview for Freshers

a. High-Level Thinking, Not Detailed Design

For freshers, interviewers are not looking for highly detailed or complex system designs. Instead, they want to see if you can:

• Think at a high level about how different components of a system interact.
• Understand scalability, data flow, and basic trade-offs (e.g., SQL vs. NoSQL).

b. Problem-Solving Skills

The main goal is to assess your problem-solving approach. You should:

• Break down the problem into components.
• Suggest reasonable approaches to handling user requests and data.
• Identify potential bottlenecks and basic solutions (e.g., caching frequently accessed data).

5. Preparing for Basic System Design Questions as a Fresher

a. Study Simple Design Problems

Focus on simple system design problems that can appear in fresher interviews, such as:

• URL shortener: Understanding database storage and mapping between long and short URLs.
• Basic messaging app: Designing a system that handles sending and receiving messages.
• File storage system: How to upload, store, and retrieve files using cloud storage.

b. Learn High-Level Concepts

Study key concepts like load balancing, database indexing, basic caching strategies, and scaling. You don’t need to dive deep into complex algorithms or architectures, but understanding how these work at a high level will help you answer basic system design questions.

c. Use Online Resources

There are online resources to help you get familiar with system design, such as:

• Grokking the System Design Interview: This course breaks down common system design problems in a simple, beginner-friendly way.
• YouTube videos and blogs on system design, which explain concepts like caching, load balancing, and high-level system architecture.

6. When System Design Becomes Important for Freshers

a. Growth into Senior Roles

As you gain experience, you’ll eventually need to learn system design more deeply. When you move into roles where you’re responsible for designing backend services or distributed systems, system design becomes a crucial skill.

b. Team Collaboration

Even as a fresher, understanding the basics of system design helps you collaborate with senior engineers and understand the overall architecture of the projects you work on.

Conclusion

While system design is not the primary focus for freshers, having a basic understanding of system components, scalability concepts, and database design can be helpful, especially at top tech companies or for backend-focused roles. Freshers should focus on understanding high-level system design concepts and practice simple design problems like a URL shortener or basic messaging app.

Key Takeaways:

1. Basic understanding of system components (frontend, backend, databases, caching).
2. Study simple system design problems like URL shorteners and messaging apps.
3. Ask clarifying questions about the system’s requirements and constraints.
4. Learn high-level concepts like scalability, caching, and database design.
5. Focus on problem-solving and breaking down the problem into manageable components.