Srikanth Guduru

Top 10 System Design Interview Questions You Must Master in 2025 (Backed by real patterns from MAANG, high-growth startups, and scaled SaaS platforms) 🔍 Over the past few weeks, I deep-dived into hundreds of system design interview experiences from engineers at Google, Meta, Uber, Netflix, Amazon, Microsoft, Stripe, and high-scale startups. 📚 I analyzed the recurring themes, real-world architectures, and what interviewers actually look for. I have curated list of the 10 most commonly asked and most impactful system design questions — the kind that separate good engineers from truly scalable thinkers. PFB Design WhatsApp — End-to-end encryption, delivery receipts, async queues, real-time updates. Design a URL Shortener (Bit.ly) — Collision-free hashing, expiration strategy, analytics layer. Design a Scalable Notification System — Fan-out model, user-specific queues, retry policies. Design an Infinite Scroll Feed — Pinterest/LinkedIn style rendering with lazy loading & viewport triggers. Design Google Docs (Real-Time Collaboration) — Operational transforms, WebSocket updates, multi-user state syncing. Design a Geo-Fencing System (like Uber) — Battery-efficient location tracking, WebSocket polling, geospatial indexing. Design an API Rate Limiter — Distributed Redis counters, token buckets, global vs user-level limits. Design Instagram — Feed generation engine, CDN optimization, follower graph modeling. Design a Chat App (Slack/Discord) — Presence handling, optimistic UI, message ordering across servers. Design a Search Autocomplete — Trie-based prefix search, ranking heuristics, latency optimizations. 🧠 Interview Tip: You don't need to know every system inside-out — but you must know how to approach scale, evaluate trade-offs, and communicate architecture under pressure. Think: ✅ Caching (Redis, CDN, browser) ✅ Queuing (Kafka, RabbitMQ) ✅ Load balancing & sharding ✅ Trade-offs (CAP theorem, latency vs consistency) ✅ Observability (logs, metrics, tracing) 🔧 My Recent Work (Aligned with System Design Thinking): Recently, I designed and architected a real-world geo-fencing module for a location-based mobile app aimed at smart city mobility use cases. The feature allowed users to define custom location zones, set proximity alerts, and manage location tracking without draining device battery. The system used efficient GPS polling, adaptive radius logic, and CDN-backed map rendering for performance. Leveraging event-driven triggers, I ensured alerts were processed in real-time while maintaining a sleek, accessible UI. 📍 This reduced battery usage by 29%, and improved alert accuracy by 40% for over 10,000+ daily users. 📌 Bookmark this post. 📩 Comment "💡" and I’ll DM you my free google doc with architecture diagrams and answer templates for all 10 questions! #hiring #faang

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𝗖𝗮𝗰𝗵𝗶𝗻𝗴 𝗦𝗲𝗿𝗶𝗲𝘀: Behind every blazing-fast read, there is a cache write strategy working in the background. Every cache write strategy comes with its own trade-offs between performance, consistency, and complexity: Let us discuss some of the most commonly used cache write strategies. 𝗪𝗿𝗶𝘁𝗲-𝗔𝗿𝗼𝘂𝗻𝗱 𝗖𝗮𝗰𝗵𝗲 In this cache write strategy, the data is directly stored in the database, bypassing the cache, and is loaded into the cache only on a subsequent read. 𝗪𝗿𝗶𝘁𝗲-𝗕𝗮𝗰𝗸 𝗖𝗮𝗰𝗵𝗲 In write-back cache, the data is written first to the cache, and then the database is updated asynchronously once in a while. By doing so, we are improving write performance but also risking data loss in case of cache failure. 𝗪𝗿𝗶𝘁𝗲-𝗧𝗵𝗿𝗼𝘂𝗴𝗵 𝗖𝗮𝗰𝗵𝗲 In this caching strategy, the data is first written to the cache, but unlike the write-back cache strategy, the data is also immediately written to the database.  For my previous posts in the Caching series, you can check them out here: 𝗧𝘆𝗽𝗲𝘀 𝗼𝗳 𝗰𝗮𝗰𝗵𝗲𝘀: https://lnkd.in/gzERggJ6 𝗗𝗶𝘀𝘁𝗿𝗶𝗯𝘂𝘁𝗲𝗱 𝗖𝗮𝗰𝗵𝗲 𝘀𝘆𝘀𝘁𝗲𝗺: https://lnkd.in/gwfqWR_V 𝗖𝗮𝗰𝗵𝗲 𝗘𝘃𝗶𝗰𝘁𝗶𝗼𝗻 𝗣𝗼𝗹𝗶𝗰𝗶𝗲𝘀: https://lnkd.in/g9HQiHKv 𝗖𝗮𝗰𝗵𝗲 𝗥𝗲𝗮𝗱 𝗦𝘁𝗿𝗮𝘁𝗲𝗴𝗶𝗲𝘀: https://lnkd.in/gS38wgF9 In my next post in the caching series, I will be talking about how CDN works.

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Trying to crack a MAANG interview? These 15 coding patterns are the secret sauce behind most of their toughest problems. Let’s decode them all, in one visual guide. 1️⃣ Sliding window – Optimize subarrays by adjusting the window instead of brute force. 2️⃣ Fast & slow pointers – Detect cycles or find midpoints with two-speed pointers. 3️⃣ Linked list reversal – Gain mastery over pointer gymnastics. 4️⃣ Two pointers – Great for solving sorted array problems efficiently. 5️⃣ Binary search – Divide and conquer your search space. 6️⃣ Bit manipulation – Power up your performance with binary tricks. 7️⃣ Prefix sum – Precompute for lightning-fast range queries. 8️⃣ Merge intervals – Sort, then merge. Clean and powerful. [Explore more in the post] 🔥 Pro tip: Instead of solving 500 LeetCode problems, master these 15 patterns and practice 3–4 problems per pattern. This isn’t just a list, it’s your coding playbook for 2025. Master these patterns, and you are ready for any whiteboard challenge that comes your way. 🔁 Save this post for your Interview preparation if you are obsessed with MAANG & top tech companies. 👉 DM me for any mentorship program to successfully land your dream tech role. Everyone Who Codes (EWC) has a simple mission: helping engineers get hired! 💼 Follow Lakshmi Marikumar for tech career & job search insights. Subscribe to our free newsletter on Substack: https://lnkd.in/gN83YA4H #systemdesign #softwareengineering #techjobs #interviews #backend #softwareengineer #softwaredeveloper #MAANG #2ndtier #hiring #jobsearch #dsa #mentorship #careeradvice

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Hi, I'm swapnil kathiari, and in this video, I address the low adoption rate of the Uber Reserve booking platform in tier 1 cities. I've identified key issues such as a cluttered user interface, insufficient marketing, and driver cancellations due to heavy workloads. My proposal includes creating a dedicated fleet for Uber Reserve, incentivizing non-cancellation, and repositioning the reserve option for better visibility. I also suggest triggering the algorithm 30 minutes prior to reserve bookings to enhance user experience. I encourage viewers to watch t these proposals and comment if there is any point missing to it. started learning about product management from Airtribe

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🧠 Top 25 System Design Interview Questions Asked at Google! 🚀 Preparing for Google or any top product-based company? These 25 high-impact system design questions will help you understand scalability, reliability & real-world architecture like a pro. 📘 Includes Questions on: ✅ Load Balancing & Caching ✅ Microservices Architecture ✅ Distributed Systems ✅ Databases & Sharding ✅ Message Queues & Event-Driven Design ✅ Designing Scalable Products (YouTube, WhatsApp, Instagram, etc.) Master these concepts → Boost your confidence → Crack system design rounds! 💡 👉 Follow Pluto Academy for more system design guides, interview prep & tech career content. #SystemDesign #GoogleInterviews #SoftwareEngineering #TechInterviews #ScalableSystems #DistributedSystems #BackendEngineering #PlutoAcademy

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