What Interviewers Really Mean When They Say “High Level First”
Learn what 'high level first' means for system design interviews, and how to outline the big picture, avoid common pitfalls, and communicate your ideas clearly.
Ever have an interviewer stop you mid-explanation and say, “Give me the high level first”?
It can be a little jarring, especially if you’re eager to show off all the details of your solution.
Don’t worry, this phrase isn’t a criticism of your knowledge.
Instead, it’s a hint that the interviewer wants you to start with the big picture before going into nitty-gritty details.
In this blog, we’ll unpack what “high-level first” really means, why interviewers say it, and how you can use this guidance to ace your system design interviews.
What Does ‘High Level First’ Mean?
When an interviewer asks for a high-level explanation, they are looking for a broad overview of your solution or design.
Think of it as describing the main idea or architecture without getting caught up in fine details.
In the context of a system design interview, “high level” refers to the overall system architecture: the major components, how they interact, and the general approach you plan to take.
It’s like giving a roadmap or outline of your solution.
This is the opposite of a low-level explanation, which would involve detailed specifics like code, exact configurations, or minute technical implementations.
By saying “high level first,” the interviewer is essentially telling you: “Paint me a picture of your solution before zooming in on any one part.”
Note: This concept isn’t limited to system design questions. Even in coding interviews, you’re often asked to describe your approach before writing any code. It’s essentially the same principle of starting with a summary before the specifics.
Why Do Interviewers Emphasize a High-Level Overview?
Interviewers, especially in system design interviews, love to see structured thinking.
Here are a few reasons they ask for a high-level overview upfront:
Big Picture Understanding: Starting with a high-level overview shows that you understand the problem in its entirety. You can identify all the key pieces of the system and how they fit together. Interviewers want to see that you’re not missing any major component.
Clarity and Communication: Explaining the broad strokes first makes it easier for the interviewer to follow your thought process. It’s like telling a story: you set the stage with the main plot (the overall design) before getting into the chapters and details. This clear communication style is crucial in collaborative engineering environments.
Guiding the Discussion: A high-level outline lets the interviewer steer the conversation to the areas they find most important. Once you’ve outlined your architecture, the interviewer might say, “Great, now tell me more about how your database will handle so many requests.” This way, you focus on the details that matter most for that particular question.
Time Management: In a typical interview (say 30-45 minutes for system design), you won’t have time to explain every little detail. By focusing on the high-level design first, you ensure all essential components are covered. Then you can deep-dive into one or two critical areas if time permits. This prevents you from spending too long on one aspect and running out of time for other key parts of the problem.
Problem-Solving Approach: Tackling a problem from the top down (big picture to details) is a hallmark of strong problem-solving. It shows that you can prioritize what’s important and break a complex problem into manageable pieces.
High Level First in System Design Interviews
This phrase comes up often in system design interviews. Interviewers expect you to outline the big picture of the system first, then drill down into details.
For example, if you’re asked to design Instagram, you should start by sketching out the main components and their roles. You might say something like: “At a high level, we have a client app, a backend service to handle user requests (posting and fetching photos), a database to store user data and posts, and a cache to speed up frequent queries.”
In one statement, you’ve covered all the core pieces without naming any specific technologies or getting into the weeds.
After giving this overview, the next step is to dive deeper into whichever part the interviewer wants to explore.
For instance, you might discuss what kind of database to use or how to design the news feed service. The key is that you only move to detailed discussion after the high-level picture is clear.
If you ever start getting too detailed too soon, a prompt like “high level first” is your cue to zoom out again.
How to Structure Your Answer (High-Level First)
So, how do you actually do this in an interview?
Here are some key steps to follow:
Clarify the requirements: Start by confirming what needs to be built and any constraints (like scale, user volume, or specific features). Knowing the goals and boundaries will guide your high-level outline.
Outline the main components: Identify the major pieces of the system and briefly state what each does. (For example, “We’ll have a client app, a backend server to handle requests, a database for storing data, and a cache for quick reads.”)
Explain interactions at a high level: Describe how those components talk to each other. Focus on the data flow or request flow between parts, without diving into internal implementation. (For instance, “The mobile app sends a request to the server, which fetches data from the database and returns a response.”)
Pause and check in: After giving this overview, stop and ask if the interviewer wants more detail on any part. This invites them to guide you to the areas they care about and shows that you can adjust your depth based on their input.
Following these steps helps you hit all the key points at a high level and keeps the conversation organized. It sets a collaborative tone. You’re essentially drawing the map together with your interviewer, then deciding which area of the map to explore further based on their feedback.
Conclusion
When an interviewer says “high level first,” they’re encouraging you to think big picture. It’s a reminder that in system design (and problem-solving in general), you should map out the broad strokes before refining the details. This approach not only makes your explanation clearer and more impressive, but it also mirrors how real-world engineering is done: start with an architecture, then iterate on specifics.
For beginners and junior developers, adopting this high-level-first mindset can be a game changer. It might feel unnatural at first, especially if you’re used to jumping straight into coding, but with practice it becomes second nature. Next time you get a system design question, take a deep breath and sketch out the main components first. Begin by describing the overall game plan. You’ll likely see the interviewer nod in approval, and you’ll find it easier to navigate the rest of the interview.
Remember: “High level first” doesn’t mean skipping details entirely; it just means making sure everyone’s on the same page about the outline before you fill in the blanks. By doing so, you show confidence, clarity, and strategic thinking. Happy interviewing!
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FAQs
Q: Why do interviewers say “high level first” during an interview?
They usually say this when you’re jumping into details too quickly. The interviewer wants you to pause and give the big-picture outline of your solution first. They value this because it shows clear, structured thinking and good communication.
Q: What is a “high-level design” in a system design interview?
It’s the broad outline of the system’s architecture. In a high-level design, you mention the main components or modules of the system, what each one does, and how they interact. It’s basically describing the system from a 10,000-foot view, without any code or minute details.
Q: How detailed should my high-level overview be?
Keep it to the major parts and their connections. Another engineer should be able to understand your solution from just your high-level description. You can leave out minor features or edge cases at this stage; those details can come later once the overview is clear.
Q: How can I practice giving high-level answers?
Take a common design problem (for example, “Design Twitter”) and practice giving a 1-2 minute high-level summary of the solution. Focus on naming the key components and describing how they relate to each other. Also, get into the habit of outlining your approach verbally before coding in algorithm questions. With time, thinking in high-level terms first will become a natural habit.