Key Takeaways

An overview of the interviewing tips and tools we discussed.

We’ve discussed a lot today. Now, let’s revisit some of the key points we went over.

Sending hireable signals

The best practices we discussed in this chapter are summarized below.

  • Navigating Trade-Offs:

    • Trade-offs occur at various stages of the design process.

    • Narrate your thought process and justify the trade-off you choose.

  • Communicating for Impact:

    • Convey that you’re collaborative, adaptable, and open to growth.

    • Ask clarifying, strategic questions.

  • Showing Your Vantage Point:

    • Discuss talking points that are relevant to the level of your desired level.

    • Be honest about what you don’t know.

  • Managing Your Time:

    • 45 minutes will fly by quickly—budget your time well.

    • Budget 5-10 minutes for clarifying questions.

    • Budget 20-25 minutes for your design process.

    • Don't discuss in-depth topics until you’ve completed your high-level design.

In this table, we’ll see a side-by-side comparison of some of these best practices and common mistakes:

System Design Interview: Dos & Don’ts

Do

Dont

Plan your 45 minutes

Dive into details without finishing your design

Ask clarifying questions

Assume you have all the requirements at the start

Justify trade-offs

Jump into a solution without explaining your decision-making

Be open to feedback

Get too attached to your initial design

Be honest about knowledge gaps

Get defensive if you’re challenged about your solution

Demonstrate the vantage point appropriate for your level

Extend your talking points to matters outside of your level

Design with the future in mind

Overlook the future needs of your system

Tip: To make these protocols second nature, treat your practice time as a mock interview. Pause while you practice design problems, and be mindful to ask questions and narrate your thought process.

Getting to the finish line

These tips and tricks can help you ensure you complete your design, so you can be sure you have time to implement the best practices we discussed in Sending Hireable Signals.

  • Lean on frameworks to help structure your design process and get you to the finish line:

    • The common 8 components are a starting point for elements used in many systems.

    • The RESHADED method can guide you through each step of your solution.

  • When facing unfamiliar problems:

    • Relate them to problems you know.

    • Ask questions that pinpoint the core problem your service should solve.

Note: As we discussed before, the System Design Interview isn’t about memorization. Even if you forget these frameworks in the interview, you will be fine, provided you’ve brought a strong understanding of System Design fundamentals and managed to convey that to your interviewer.