Shruti Gupta

There are two hard problems in distributed systems: 2. Exactly-once message delivery 1. Message ordering 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery 2. Exactly-once message delivery

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Is CDN a reverse proxy, just like a load balancer or an API gateway? Yes. While LB and API gateway fit the classic definition of a Reverse Proxy, CDN is also a reverse proxy with caching as its primary purpose. Like any other reverse proxy, 1. CDN acts as a single point of entry for client requests, 2. CDN abstracts out different origins configured behind it 3. CDN can also route the requests across multiple origins depending on the route-matching configuration. Hence, the deduction is on point, and LB, API Gateway, and CDN are all examples of Reverse Proxies. I elaborated on CDN, as it is an unconventional example. ps: I love how the comments on my YouTube videos are also no-fluff and filled with thought-provoking questions. Thank you for asking such great questions. By the way, the question was asked in my recent video on Forward and Reverse Proxy. In the video, I went into highly practical details with real-world examples and stories from my life. give it a watch and subscribe - youtu.be/HrG0MHkSsCA btw, enrollments open for sys design June cohort, about 30 seats left - arpitbhayani.me/course

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SDE-1 – Learning Phase ------------------------ You’re new. You get small tasks. Seniors tell you what to do. Your job is to write clean code and learn how things work. It’s okay to make mistakes just keep learning. DSA: Very important helps you solve problems fast. System Design: Not expected yet, just basics. SDE-2 – Owning Things ------------------------ You now build full features on your own. You plan, code, test, and fix. Juniors ask you for help. You know the system well and people trust you to get things done. DSA: Still useful, but not the focus. System Design: Very important you’re expected to design services/modules. SDE-3 – Guiding Others ------------------------ You don’t just build you design. You think about big problems, help many teams, and guide juniors and SDE-2s. You make sure the system is solid and scalable. DSA: Rarely used day-to-day, only in hiring. System Design: Super important this is your main job. #SDE #preprations

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🚨 Want to crack your next Mphasis (or any IT company) interview? Here’s the EXACT list of questions I faced + my prep strategy 👇 🔹 Round 1 – Online Coding (Arrays + Strings) → Rotate an array by k steps (optimize beyond brute force) → Find the longest substring without repeating characters 🔹 Round 2 – OOPs + Coding → Explain concepts: Abstraction, Encapsulation, Polymorphism, Inheritance → Design a Library Management System (OOP design) 🔹 Round 3 – SQL + Problem Solving → Queries using joins and subqueries + window functions → Puzzle: Arrange numbers into a magic square I answered all of these technical questions but when the managerial questions came, I stumbled💔 And yes, just like you, even I used to think that the managerial rounds are the easiest but trust me, they are not. So, prepare for these rounds beforehand by giving mocks to senior SDEs like me💯 Get started with a FREE call here → https://lnkd.in/ddRB7jK7 They won’t just ask random questions in the name of a mock interview. These SDEs are on hiring panels at MAANG and PBCs, so they’ll ask you company-specific questions, spot your gaps and help you improve with 1:1 training!🚀 #interviewexperience #rejection #sde #techinterview #paidpartnership #tech

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I recently had the opportunity to do an early review of "Modern Concurrency in Java" by A N M "Bazlur" Rahman, and I wanted to share why this book stands out in the crowded field of Java literature. As someone who has worked with Java for over 15 years, I've seen concurrency evolve from a complex necessity to something more approachable with modern features. This book captures that evolution beautifully. What makes this book special is how Bazlur gradually builds each concept on the previous one. You start with the fundamentals of threads, then move through the evolution of concurrent programming in Java, finally arriving at the latest features like virtual threads, structured concurrency, and scoped values. The progression feels natural. Rather than jumping straight into the new features, you understand why they were needed and what problems they solve. This approach reduces the cognitive load of learning these complex topics, making them accessible even if you're not a concurrency expert. For senior developers, the book offers deeper insights into how these features actually work under the hood. For those newer to concurrent programming, it provides a solid foundation without overwhelming you with unnecessary complexity. Virtual threads particularly caught my attention. The book explains not just how to use them, but when they make sense and how they compare to traditional approaches. This practical perspective helps you make informed decisions in your own projects. Whether you're building microservices that need to handle thousands of concurrent requests, or you simply want to understand what all the excitement about Project Loom is about, this book provides the knowledge you need. I highly recommend "Modern Concurrency in Java" for any Java developer who wants to master concurrent programming or stay current with Java's latest capabilities. Book link: https://lnkd.in/d-HNKGPT #Java #ConcurrentProgramming #VirtualThreads #BookReview #ProjectLoom #TechBooks #SoftwareEngineering

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🔍 How Spring Boot Handles Each API Request Internally? Ever wondered what happens when your API endpoint receives a request in Spring Boot? Here's a quick breakdown 👇 1️⃣ Request Lifecycle (Step-by-Step) 🌐 Client sends HTTP request 🏗 Tomcat receives and assigns a thread 🎯 DispatcherServlet acts as the Front Controller 🗺 HandlerMapping finds the right @Controller method ⚙️ HandlerAdapter calls your method 🔄 HttpMessageConverters serialize/deserialize request & response 🧹 ThreadLocal cleaned up & thread returns to pool 2️⃣ Why Each Request Has Its Own Data? Each request runs on its own thread from Tomcat’s pool Spring uses ThreadLocal to store request-scoped data like: - HttpServletRequest - SecurityContext (Spring Security) - Locale & Transactions 💡 Example: HttpServletRequest currentRequest = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()) .getRequest(); System.out.println("Client IP: " + currentRequest.getRemoteAddr()); Takeaway Spring Boot’s DispatcherServlet + ThreadLocal combo ensures: ✅ Thread safety per request ✅ Clean separation of data ✅ Simplified request handling Have you ever debugged ThreadLocal memory leaks in Spring? Share your experience! 🚀 #SpringBoot #Java #BackendDevelopment #SpringMVC #Microservices #ThreadLocal #SpringSecurity

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Continuing the topic from my yesterday's poll, Not All Modules from the lightning/uiRecordApi API support wire call or imperative call. So to make things clearer, here’s a simple visual reference of the most commonly used UI API modules and whether they support imperative or wire usage.👇 If this was helpful, make sure to follow me here on LinkedIn and on YouTube — I share quick, practical Salesforce tips like this every week! #Salesforce #LWC #LightningWebComponents #SalesforceDevelopers #Apex #UIAPI #TrailblazerCommunity #getRecord #DeveloperTips

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Our team uses Oracle Visual Builder Studio (VBS) for delivering Oracle Redwood User Experience (redwood.oracle.com) focused customer solution for Fusion Digital Government. The "Build Visual Applications Using Oracle Visual Builder Studio" course was a 3 Days training program to get going with Visual Builder Studio and experience improved experience for packaging and deploying Visual Applications • Low-code developers, who want to create web or mobile apps using a visual designer • Oracle Cloud Applications developers, who need to extend their apps with business-specific customizations • Experienced programmers, who want to modify the source code for web and mobile apps created by others, or develop bespoke apps using the web programming language of their choice • Fusion Applications developers who will create or extend Fusion Applications with Visual Builder Benefits Rapidly design, build, and deploy visual applications using a visual development environment with integrated agile and collaborative development. Revised the following concepts: • About Visual Builder Studio and anatomy of visual applications • To configure and manage service connections in visual apps • To connect to data with business objects • To implement the visual functionality • To enhance the user experience of visual apps • Manage, build, package and deploy visual apps #Oracle #OracleUniversity Oracle Oracle University #OracleVisualBuilderStudio #OracleVisualBuilder

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The simplest way to understand REST API.. Think of it like ordering food at a restaurant: You (the client) → place an order (request) → kitchen (server) prepares it → waiter brings it back (response). That’s a REST API – simple, fast, and everywhere! #API #RESTAPI #TechMadeSimple #Programming #Backend

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💥 𝗦𝗣𝗥𝗜𝗡𝗚 𝗕𝗢𝗢𝗧 𝗜𝗡𝗧𝗘𝗥𝗩𝗜𝗘𝗪 𝗖𝗛𝗘𝗔𝗧 𝗦𝗛𝗘𝗘𝗧 (𝗕𝗮𝘀𝗶𝗰 → 𝗔𝗱𝘃𝗮𝗻𝗰𝗲𝗱) 💥 Are you preparing for your next Java | Spring Boot interview? Here’s the ultimate Q&A roadmap that covers everything, from core basics → advanced real-world concepts. 👉 𝗦𝗮𝘃𝗲 𝘁𝗵𝗶𝘀. 👉 𝗥𝗲𝘃𝗶𝘀𝗲 𝗯𝗲𝗳𝗼𝗿𝗲 𝘆𝗼𝘂𝗿 𝗯𝗶𝗴 𝗱𝗮𝘆. 👉 𝗖𝗿𝗮𝗰𝗸 𝘁𝗵𝗲 𝗶𝗻𝘁𝗲𝗿𝘃𝗶𝗲𝘄. 🔰 𝗕𝗔𝗦𝗜𝗖𝗦 (𝗞𝗶𝗰𝗸𝘀𝘁𝗮𝗿𝘁) ✨ What is Spring Boot & how it differs from Spring Framework? ✨ Features of Spring Boot ✨ Spring Boot Starter & Auto-Configuration ✨ @SpringBootApplication explained ✨ Embedded Server (Tomcat by default) – how to change it ✨ Changing port numbers ✨ Spring Boot Actuators & Spring Initializr 📝 𝗔𝗡𝗡𝗢𝗧𝗔𝗧𝗜𝗢𝗡𝗦 (𝗠𝘂𝘀𝘁-𝗞𝗻𝗼𝘄) 🔹 @Component vs @Service vs @Repository vs @Controller 🔹 @RestController vs @Controller 🔹 @GetMapping vs @PostMapping vs @RequestMapping 🔹 @Configuration vs @Component 🔹 @Bean, @Qualifier, @Value explained ⚙️ 𝗜𝗡𝗧𝗘𝗥𝗡𝗔𝗟𝗦 (𝗗𝗲𝗲𝗽 𝗗𝗶𝘃𝗲) 🔧 IoC vs Dependency Injection 🔧 ApplicationContext vs BeanFactory 🔧 Bean lifecycle explained 🔧 Singleton vs Prototype scope 🔧 Circular dependencies handling 📂 𝗖𝗢𝗡𝗙𝗜𝗚𝗨𝗥𝗔𝗧𝗜𝗢𝗡 (𝗘𝘃𝗲𝗿𝘆𝗱𝗮𝘆 𝗦𝘁𝘂𝗳𝗳) 📌 application.properties vs application.yml 📌 Profiles in Spring Boot (@Profile) 📌 DB connection (MySQL/Postgres) 📌 DevTools & Externalized Config 🌍 𝗥𝗘𝗦𝗧 + 𝗦𝗘𝗖𝗨𝗥𝗜𝗧𝗬 (𝗛𝗼𝘁 𝗧𝗼𝗽𝗶𝗰𝘀) 🛡 Building REST APIs in Spring Boot 🛡 Exception Handling (@ControllerAdvice) 🛡 Securing APIs → Spring Security vs OAuth2 🛡 Enabling CORS 💾 𝗗𝗔𝗧𝗔 𝗟𝗔𝗬𝗘𝗥 (𝗝𝗣𝗔 + 𝗛𝗶𝗯𝗲𝗿𝗻𝗮𝘁𝗲) 📊 What is Spring Data JPA? 📊 CrudRepository vs JpaRepository vs PagingAndSortingRepository 📊 Custom queries in JPA 📊 Lazy Loading vs Eager Loading 📊 Transactions (@Transactional) ⚡⚡ 𝗔𝗗𝗩𝗔𝗡𝗖𝗘𝗗 (𝗥𝗲𝗮𝗹-𝗪𝗼𝗿𝗹𝗱) 🚀 Monolithic vs Microservices vs Serverless 🚀 Caching with @Cacheable 🚀 Async Processing with @Async 🚀 Integration with Kafka / RabbitMQ 🔥 If you can confidently answer these → you’re already ahead of 90% of candidates. 💬 Want me to share detailed answers to each? Comment YES below 👇 📌 Save this post & share with someone preparing 🙌 #SpringBoot #Java #Microservices #BackendDevelopment #SpringFramework #SystemDesign #SpringSecurity #JavaDeveloper #Hibernate #SpringDataJPA #Kafka #TechCareers #InterviewPreparation #CodingLife #100DaysOfCode

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Eating the exception poisoning the app!, Handling the errors properly and propagates the exception/logical error to the controller or the use case, will be too helpful to write a robust logic and handles any case in a proper way. We have 2 options. 1. Use Result<T> This is too helpful class holds the data or exception, and it's part of kotlin standard library (so it's too stable), but the limitation is, it only propagates the T or exception, not other errors, and if you uses when statement you will be forced to use else. Something like .onSuccess { user -> println(user.name) } .onFailure { error -> when (error) { is NetworkException -> println("Failed to fetch user") is ParsingException -> println("Failed to parse user") else -> println("Unhandled error") } } 2. Use Either<T, E> This is the best solution (until kotlin 2.4 released!) return type will be either data T, or Error E, and this error could be a sealed class, which means it will be exhaustive when, and it's functional, which means you can flatmap and mapLeft and much more (Documentation link https://lnkd.in/dTQ_qdVd) Note: In kotlin conf 2025, there are an announcement for kotlin 2.4 for new class types called error and the union type only for Rich errors, something like error class NetworkError error class ParsingError fun getUser(): User | NetworkError | ParsingError Happy coding 😄 #kotlin #android #kmp #cmp #software_engineering

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The SDE2 → SDE3 Reality Check 💫 Over the last few hiring cycles, an interesting trend has been hard to ignore. A large pool of engineers in the market today are positioned — and paid — at an SDE2 level, but aspire to transition into SDE3 roles. The ambition is great to see, but there’s a clear skill depth and expectations gap that often surfaces during interviews. Many SDE2 candidates are drawing compensation that aligns closer to senior-level roles, but when it comes to system design depth, architectural thinking, scalability decisions, debugging complexity and ownership — the jump to SDE3 isn’t always an easy one. This creates a two-fold challenge for companies: 🔍 Finding strong backend engineers who truly meet SDE3 bar 💰 Balancing expectations vs. current market pay benchmarks The demand for senior-level engineers is massive, but the supply of truly production-scale, architecture-driven backend talent remains limited — making this one of the toughest hiring brackets today. Not a blocker, but a gap worth acknowledging. A space where upskilling, exposure to large-scale systems, and real ownership can make a huge difference. Curious to know — what’s your take on the SDE2 → SDE3 skill gap in the market today? Would love to hear different perspectives. 💭 #techdeapth #hiring #team #skillgap #compensationbenchmark #salarybar #fitment #hiringbar #scaleup #design

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🌟 The Most Underrated Skill in ServiceNow: Thinking in “Platforms,” Not “Tickets” A lot of people learn ServiceNow by learning forms, fields, tables, flows, and catalog items. But the real transformation happens when you stop thinking like a ticket resolver… and start thinking like a platform designer. Here’s what that shift looks like: 🔹 FROM “How do I fix this Incident?” TO “How do I eliminate this Incident from ever happening again?” 🔹 FROM “Which table does this live on?” TO “How do I design a scalable data model?” 🔹 FROM “Let’s automate this one request.” TO “How do I build a reusable pattern for all future automations?” 🔹 FROM “Let me write this script.” TO “Should this even be a script, or can configuration solve it cleaner?” 🔹 FROM “My job is to deliver.” TO “My job is to improve the entire digital ecosystem.” This shift is what turns a ServiceNow developer into a ServiceNow architect, and eventually… a digital transformation leader. The platform rewards those who: ✨ Think long-term ✨ Build reusable components ✨ Avoid tech debt ✨ Focus on user experience ✨ Automate with purpose ✨ See the platform as an enterprise engine — not a tool If you’re growing in your ServiceNow career, start practicing this shift daily. It’s the real career cheat code nobody talks about. #ServiceNow #DigitalTransformation #NowPlatform #CareerGrowth #Automation #ITSM #Developers #TechLeadership

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🚀 Spring Boot Interview Experience: Real-World Scenario-Based Questions I’m sharing some of the scenario-based questions I was asked — hoping it helps other developers who are preparing for backend or full-stack roles. 👇 Key Spring Boot Scenario-Based Questions: 1. OutOfMemoryError Troubleshooting "Your Spring Boot application is suddenly throwing an OutOfMemoryError. How would you investigate and resolve it?" 2. Resilient Microservice Communication "In a microservices-based architecture using Spring Boot, how would you handle communication failures between services?" 3. Securing APIs Without Spring Security "What steps would you take to secure REST APIs if you're not using Spring Security?" 4. Integration Testing with External Dependencies "How would you write integration tests for a controller that depends on third-party or external services?" 5. Creating a Custom Spring Boot Starter "You need to modularize internal tools into a custom Spring Boot starter. What’s your strategy?" 6. Optimizing Slow Startup Time "Your application startup is slow. What areas would you inspect or optimize to improve it?" 7. Handling Production Rollbacks "A faulty deployment made it to production. How would you roll it back safely in a Spring Boot environment?" #SpringBoot #Java #BackendEngineering #Microservices #TechInterviews #SystemDesign #SpringFramework #InterviewPreparation #DeveloperCommunity #CleanCode #SoftwareEngineering

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