If you’re preparing for a Google interview for the L4 (mid-level software engineer) position, you might be wondering: Do they ask system design for L4 at Google? The short answer is: sometimes. It depends on the team, the specific role, and the interviewer.
Here’s a deep dive into what you should expect when it comes to system design for L4 at Google and whether it’s something you need to focus on in your preparation.
1. Is System Design Required for L4?
For L4 positions, system design for L4 at Google is not typically a core requirement like it is for senior roles (L5 and above). However, it can still appear, especially in the following cases:
- You have 3+ years of experience.
- You’re applying for a backend or infrastructure-heavy role.
- The interviewer wants to test your design thinking.
If system design does come up, the expectation is basic system design knowledge, not the in-depth distributed systems questions faced by L5+ candidates. The focus will be more on how you think about design and scaling at a smaller scale.
2. What Kind of System Design Questions Might Appear?
If you do encounter system design for L4 at Google, expect the questions to focus on smaller-scale designs or high-level architecture. Common questions might include:
- Design a URL shortener (like bit.ly)
- How would you structure a basic messaging queue?
- Design a simple rate limiter for an API
- How would you store and retrieve large amounts of logs efficiently?
Expect to discuss trade-offs, but you won’t be grilled on advanced topics like database sharding or event-driven architectures at this level.
3. How Deep Should You Go?
The depth of system design for L4 at Google is moderate. While you don’t need to dive into the advanced topics of distributed systems, you should focus on these key areas:
- Data modeling: What type of database would you use? Consider SQL vs NoSQL.
- Basic scalability: How would you handle increasing traffic or load?
- Caching strategies: Where and when would you use caching solutions?
- APIs and communication: How do system components interact with each other?
While it’s not necessary to understand the CAP theorem, consensus algorithms, or microservices orchestration at L4, having a solid understanding of these basics will help you approach the problem effectively.
4. When Can You Skip System Design Prep?
If you’re applying for an L4 role that is highly frontend-focused, machine learning-heavy, or tools/infrastructure-based, chances are you won’t get system design questions. Instead, you’ll focus on the following areas:
- Data structures & algorithms (DSA): Expect 2-3 rounds of LeetCode-style problems.
- Code quality & debugging: Demonstrating your ability to write clean, efficient, and bug-free code.
- Behavioral interviews: Google values team players who can collaborate effectively in a team.
In these cases, your preparation should focus on strengthening your coding skills and mastering data structures and algorithms.
Should You Prepare for It?
It’s always better to be prepared. While system design for L4 at Google is not guaranteed, having a solid grasp of the basics will prepare you for any surprises during the interview. Even if you’re not asked a system design question, this knowledge can help you stand out in the interview.
What’s been your experience? Did you encounter system design questions in your L4 interview at Google? Share your thoughts below!
