How to Ace Your Next Coding Interview: Tips from FAANG Engineers

Landing a job at a FAANG company (Facebook/Meta, Amazon, Apple, Netflix, Google) or any top tech company is a big goal for many developers. These interviews can feel scary, but they are also very predictable once you understand the process and prepare the right way.

This guide breaks down how FAANG-style interviews work, what they actually test, and how you can build a step-by-step plan to crack them — even if you're not from a top college or big-name company.

🔍 Understanding the FAANG Interview Process

While each company has its own flavor, the interview process usually follows a similar structure.

Typical Interview Structure (High-Level)

Recruiter Call (15–30 minutes)

• Discuss your background and interests
• Confirm role, location, salary expectations
• High-level skill check (languages, experience)

Technical Phone Screen / Online Round (30–60 minutes)

• 1–2 coding questions (DSA) on a shared editor
• Sometimes on platforms like HackerRank, CodeSignal, or in-browser tools
• Light behavioral questions ("Tell me about yourself", "Why here?")

Onsite / Virtual Onsite (4–6 rounds)

Typically includes:

• 2–3 Coding rounds (data structures & algorithms)
• 1 System Design round (for mid/senior roles)
• 1 Behavioral / Culture Fit round
• 1 Leadership / Management round (for senior positions)

Many "onsites" are now virtual, but the structure is very similar.

What They're Really Looking For

Across all rounds, interviewers look for the same core things:

• Technical Excellence: Can you write correct, clean, efficient code under time pressure?
• Problem-Solving Approach: Do you break problems into steps? Can you reason about edge cases and trade-offs?
• Communication: Do you explain your thinking clearly? Do you ask questions when unsure?
• Collaboration & Culture Fit: Would people be happy working with you? Are you respectful, open, and humble?
• Growth Mindset: Do you learn from mistakes, accept feedback, and improve quickly?

Think of the interview as testing:

👉 How you think, not just what you know.

✅ Pre-Interview Preparation

1. Master the Fundamentals (No Shortcuts Here)

You don't need to know every algorithm in the world, but you must be solid in the basics.

Core Data Structures & Algorithms

Focus on these first:

• Arrays & Strings
• Linked Lists
• Stacks & Queues
• Hash Tables / Hash Maps
• Trees & Graphs
• Binary Trees, BSTs
• BFS, DFS
• Heaps / Priority Queues
• Sorting & Searching
• Dynamic Programming (common patterns)

Time & Space Complexity

You should be comfortable with:

• Big-O notation: O(1), O(log n), O(n), O(n log n), O(n²), etc.
• Comparing approaches: brute force vs optimized
• Knowing when extra memory (like a hash map) is worth it

Tip: After solving a problem, always ask: "Can I make this faster or use less space?"

2. Practice Coding Problems (The Smart Way)

You don't have to solve 1,000 problems. You need to cover patterns deeply.

Recommended Platforms

• LeetCode (strongly recommended, especially for FAANG-style questions)
• HackerRank
• CodeSignal
• InterviewBit

Problem Types to Focus On

• Arrays & Strings (two pointers, sliding window)
• Hash Map problems (frequency, lookups, grouping)
• Tree traversals (preorder, inorder, postorder, BFS)
• Graph problems (BFS, DFS, shortest path basics)
• Recursion + Backtracking (subsets, permutations)
• Dynamic Programming (knapsack, subsequences, paths)

Tip: Treat each problem as a pattern, not just a one-time question.

3. Use Mock Interviews to Simulate the Real Thing

Practicing alone is great. Practicing with pressure is better.

You can practice with:

• Friends or colleagues
• Online mock interview platforms (e.g., Pramp, Interviewing.io, etc.)
• Recording yourself solving problems out loud

Focus on:

• Explaining your thought process clearly
• Managing time (45-minute round)
• Staying calm when stuck

4. Build a Simple 8–12 Week Plan

Example:

• Weeks 1–2: Arrays, Strings, Hash Maps, basic Trees
• Weeks 3–4: Graphs, Recursion, Backtracking
• Weeks 5–6: Dynamic Programming patterns
• Weeks 7–8: System Design basics + mixed problem sets
• Weeks 9–12: Full mock interviews + revising weak areas

Consistency beats intensity.

🎤 During the Interview

1. Use a Clear Problem-Solving Framework

Before touching the keyboard, do this:

1. Clarify the problem

• Restate in your own words
• Confirm input/output, constraints, edge cases

1. Think of examples

• Small inputs
• Edge cases (empty, large, negative, duplicates, etc.)

1. Propose an approach

• Start simple, then optimize
• Discuss trade-offs

1. Code cleanly

• Meaningful variable names
• Logical structure and helper functions

1. Test your code

• Use the examples you discussed
• Try edge cases

You can think of this like an extended version of STAR applied to problem solving:

• S – Situation: Restate and clarify the problem
• T – Task: Identify exactly what you must return/do
• A – Action: Choose and implement an approach
• R – Result: Verify correctness and complexity

2. Communication Strategy: Think Out Loud

Interviewers can't read your mind. You must speak.

Example of good communication:

// Example of good communication
"I think we can solve this using a two-pointer technique.
// Plan:
// 1. Sort the array (O(n log n))
// 2. Use two pointers from start and end
// 3. Move them based on the current sum
// This gives us O(n log n) time and O(1) extra space."

Ask Clarifying Questions

Good questions include:

• "Can I assume the input is always valid?"
• "What should I return if no solution exists?"
• "What are typical and maximum input sizes?"

This shows maturity and realism, not weakness.

3. Coding Best Practices (They Notice This)

Write code like someone else will maintain it.

Good Example

function findTwoSum(nums, target) {
  const numIndex = new Map();

  for (let i = 0; i < nums.length; i++) {
    const complement = target - nums[i];

    if (numIndex.has(complement)) {
      return [numIndex.get(complement), i];
    }

    numIndex.set(nums[i], i);
  }

  return []; // or null based on requirements
}

Bad Example

function f(a, b) {
  for (let i = 0; i < a.length; i++) {
    for (let j = i + 1; j < a.length; j++) {
      if (a[i] + a[j] === b) return [i, j];
    }
  }
  return [];
}

The second one works, but it's:

• Slower (O(n²) vs O(n))
• Harder to read
• Harder to explain

Clean code + good complexity = strong signal.

🧩 Common Interview Patterns (You Must Know These)

1. Two Pointers

Use for:

• Palindromes
• Pair sums in sorted arrays
• Removing duplicates in-place

function isPalindrome(s) {
  let left = 0;
  let right = s.length - 1;

  while (left < right) {
    if (s[left] !== s[right]) {
      return false;
    }
    left++;
    right--;
  }

  return true;
}

2. Sliding Window

Use for:

• Maximum/minimum subarray sums
• Longest substring with some condition
• Counting subarrays with certain properties

function maxSubarraySum(arr, k) {
  let maxSum = 0;
  let windowSum = 0;

  for (let i = 0; i < k && i < arr.length; i++) {
    windowSum += arr[i];
  }

  maxSum = windowSum;

  for (let i = k; i < arr.length; i++) {
    windowSum = windowSum - arr[i - k] + arr[i];
    maxSum = Math.max(maxSum, windowSum);
  }

  return maxSum;
}

3. Hash Map / Dictionary

Use for:

• Frequency counting
• Fast lookups
• Grouping items (like anagrams)

function groupAnagrams(strs) {
  const map = new Map();

  for (const str of strs) {
    const key = str.split('').sort().join('');

    if (!map.has(key)) {
      map.set(key, []);
    }

    map.get(key).push(str);
  }

  return Array.from(map.values());
}

These patterns appear again and again in FAANG-style interviews.

🏗️ System Design Basics (For Mid/Senior Roles)

You don't need to design Google Search from scratch on day one. Start with core concepts.

1. Scalability Concepts

• Horizontal scaling: Add more machines
• Vertical scaling: Give one machine more power
• Load balancing: Distribute traffic across servers

2. Database Design

• SQL: Structured schema, ACID, great for transactions
• NoSQL: Flexible schema, high throughput, often used for large-scale apps

3. Caching

• Use in-memory stores (e.g., Redis, Memcached)
• Cache hot data (e.g., frequently accessed user profiles)
• Consider cache invalidation strategy

4. Common System Design Question: URL Shortener

When asked "Design a URL shortener (like bit.ly)" think in steps:

1. Functional requirements (shorten, redirect, analytics?)
2. Non-functional (availability, latency, scale)
3. API design (POST /shorten, GET /:code)
4. Data model (short_code ↔ long_url)
5. Short code generation strategy
6. Scaling: sharding, caching, replication

You don't need to be perfect — you need to think and iterate.

🧠 Behavioral Questions (Don't Ignore These)

These can decide your offer, especially at FAANG.

Common Questions

• "Tell me about a challenging project you worked on."
• "How do you handle disagreements with teammates?"
• "Describe a time you failed. What did you learn?"
• "Why do you want to work at [Company]?"

Use the STAR Method

• S – Situation: Brief context
• T – Task: What you needed to do
• A – Action: What you actually did
• R – Result: What happened, with numbers if possible

Example:

"We were behind schedule by 3 weeks on a release… I proposed X, coordinated Y, and the final release improved performance by 30% and met the new deadline."

Prepare 5–7 strong stories covering:

• Conflict resolution
• Leadership / ownership
• Failure & learning
• Working under pressure
• Helping others / mentoring

🏢 Company-Specific Focus Areas (High-Level)

These are general patterns (always check the latest info from the company):

Google

• Strong focus on algorithms and data structures
• Expect follow-up "what if" questions on your solution
• Clean, readable code is heavily valued

Amazon

• Leadership Principles are critical
• Behavioral questions appear in every round
• System design is common even for mid-level roles

Meta (Facebook)

• Fast-paced, product-focused mindset
• Expect questions about impact and metrics
• System design for news feed, messaging, posts, etc.

Apple

• Strong emphasis on quality and user experience
• Expect deeper dives into projects you've done
• Sometimes more platform-specific (iOS/macOS) questions

Netflix

• Focus on ownership, autonomy, and impact
• Heavy systems and distributed systems emphasis
• Expect culture-fit discussions around freedom and responsibility

📩 Post-Interview Follow-Up

1. Thank You Notes

Good practice, especially at senior levels:

• Send within 24 hours
• Mention something specific you discussed
• Keep it short and genuine

2. References

For some roles, companies ask for references:

• Inform your references in advance
• Share the job description and your resume
• Thank them after they support you

🚫 Common Mistakes to Avoid

1. Technical Mistakes

• Jumping into code before fully understanding the problem
• Ignoring edge cases and constraints
• Not analyzing time and space complexity
• Not testing your code with examples

2. Communication Mistakes

• Staying silent while thinking
• Being afraid to ask clarifying questions
• Getting stuck and not discussing alternate approaches
• Sounding defensive when given hints

3. Behavioral Mistakes

• Giving generic answers ("I work hard", "I'm a team player")
• Speaking badly about previous employers or teammates
• Not having concrete examples with results
• Not showing any curiosity about the company/team

🌟 Success Stories (Summarized)

Case Study 1: Sarah – From Mid-Level Dev to Google

• Prepared for ~6 months
• Solved ~200+ LeetCode problems (focusing on patterns, not just volume)
• Weekly mock interviews with friends and online platforms
• Practiced system design on weekends
• Prepared detailed behavioral stories with measurable outcomes

Why she succeeded: Consistency, pattern-based practice, strong communication, and well-prepared stories.

Case Study 2: Mike – Startup Dev to Amazon

• Highlighted ownership and customer focus from startup experience
• Mapped his stories to Amazon's Leadership Principles
• Prepared both coding and system design
• Practiced answering "Why Amazon?" and behavioral questions deeply

Why he succeeded: He connected his real experience directly to what Amazon values.

📚 Resources for Continued Learning

Books

• Cracking the Coding Interview – Gayle Laakmann McDowell
• System Design Interview – Alex Xu
• Elements of Programming Interviews – Adnan Aziz et al.

Online Resources

• LeetCode / InterviewBit problem sets
• Grokking the System Design Interview (for patterns)
• Mock interview platforms (Pramp, Interviewing.io, etc.)

🏁 Final Tips for Success

1. Start Early – Give yourself at least 3–6 months if you're starting from scratch.
2. Be Consistent – Daily practice beats weekend marathons.
3. Focus on Patterns, Not Problems – Learn approaches you can reuse.
4. Practice Talking – Your thinking process is as important as your final answer.
5. Review Every Interview – Note what went well and what didn't.
6. Don't Take Rejections Personally – Use them as feedback, not verdicts.
7. Network Smartly – Referrals can improve your chances of getting interviews.

Remember: FAANG interviews are hard, but not magical. With structured preparation, pattern-based practice, and a calm mindset, you can absolutely reach that level — whether your dream is FAANG or any other top-tier company.

Good luck with your interviews! 🚀