Anish Karlekar’s Post

In 2026, the biggest performance gains aren’t coming from clever hooks or micro-optimizations. They’re coming from architectural decisions: • Server-first rendering with Server Components • TypeScript as the default, not an option • Smaller, single-responsibility components • Suspense-driven data flows • Feature-based project structure • Using the right state tool for the right job (local, global, server) The React Compiler is pushing us toward predictable, pure code, and frameworks like Next.js are making “ship less JavaScript” the new baseline for performance. I put together a practical guide that focuses on scalability, maintainability, and real-world performance — not just theory. If you’re working on modern React applications, especially in large codebases, this is the direction the ecosystem is moving. 🔗 https://lnkd.in/eezMdiMx Curious how others are structuring their React apps in 2026 — are you fully server-first yet, or running hybrid? #React #TypeScript #FrontendArchitecture #WebPerformance #SoftwareEngineering #NextJS

Over the last few years working with Angular in real production projects, I’ve realized one thing: Angular doesn’t become complex because of the framework. It becomes complex because of how we structure it. When I started, I used to focus on “making it work.” Now I focus on “making it maintainable.” Here are a few practices that genuinely changed the way I write Angular applications: 1. Don’t dump everything into one component Early in my career, I used to put API calls, business logic, and UI logic inside the same component. It works… until the file becomes 600+ lines. Now I separate responsibilities: • Component → handles UI and interaction • Service → handles API and business logic Simple rule: if logic can be reused or tested separately, move it to a service. 2. Avoid unnecessary subscriptions If you are manually subscribing everywhere and forgetting to unsubscribe, memory leaks will happen. Using: • async pipe in templates • switchMap instead of nested subscriptions • takeUntil for cleanup makes the code cleaner and safer. 3. Use OnPush when performance matters For small apps, default change detection is fine. But in larger applications with heavy UI, OnPush improves performance and forces you to follow proper immutable data patterns. It also makes you think more clearly about how data flows. 4. Structure folders by feature, not by type Instead of: components/ services/ models/ I prefer: auth/ dashboard/ booking/ shared/ Because real applications grow by features, not by file types. 5. Stop using “any” Using any feels fast. But it removes TypeScript’s biggest advantage — safety. Defining proper interfaces takes a little time but saves debugging hours later. 6. Write readable code, not clever code If someone else cannot understand your logic quickly, it’s not good code. In big teams, clarity matters more than smart tricks. The biggest shift for me was this: Don’t write Angular code to finish the task. Write Angular code assuming someone else will maintain it for the next 3 years. That mindset changes everything. What’s one Angular mistake that completely changed how you write code today? #Angular #FrontendDevelopment #CleanCode #SoftwareEngineering

🚀 Reusable Logic in React (Custom Hooks) Instead of repeating logic across components, I started extracting it into reusable hooks. 🧠 Problem Fetching data in multiple components = duplicated logic ⚙️ Solution → Custom Hook import { useState, useEffect } from "react" function useFetch(url) { const [data, setData] = useState(null) useEffect(() => { fetch(url) .then(res => res.json()) .then(setData) }, [url]) return data } ⚡ Usage const data = useFetch("/api/users") 💡 Why It Matters • Cleaner components • Reusable logic • Better separation of concerns • Scalable architecture 🎯 Takeaway: Good developers write code. Great developers write reusable systems. Moving towards more scalable React architecture. 💪 #ReactJS #CustomHooks #FrontendDeveloper #CleanCode #MERNStack #SoftwareEngineering

📝 Excited to Share My Latest Blog! I’m excited to share my latest blog where I explored the Architecture of Node.js and Libuv and how they power modern backend applications. In this article, I explained: 🔹 How the Event Loop works 🔹 The role of Libuv in asynchronous I/O operations 🔹 How Node.js handles multiple requests with a single thread 🔹 The importance of non-blocking architecture in scalable systems Understanding the internal architecture of Node.js helped me see how high-performance backend systems are built and why Node.js is widely used for building scalable applications. Huge thanks to Hitesh Choudhary Sir, Piyush Garg Sir, and the amazing Chai Aur Code community for sharing such valuable knowledge and helping developers understand core concepts of backend development. 📖 Read the full blog here: https://lnkd.in/gAn2CvJh I would love to hear your feedback and suggestions! 🙌 #NodeJS #BackendDevelopment #WebDevelopment #JavaScript #LearningInPublic #ChaiAurCode #FullStackDevelopment

💻 Angular Important Questions. 💻 💻 1. What Are Observables and How Are They Used inAngular? Answer:Observables (from RxJS) represent a stream of asynchronous data. Angular heavily uses observables for HTTP requests, form changes, and event handling. Example: typescript this.http.get<User[]>('/api/users') .subscribe(data => this.users = data); 💻 2. How Do You Optimize the Performance of anAngular Application? Answer:Key performance techniques include: •  Lazy loading modules •  Using OnPush change detection strategy •  Avoiding memory leaks via takeUntil and unsubscribe •  AOT compilation and tree shaking •  Minifying and compressing assets Example: Using OnPush: typescript @Component({ changeDetection: ChangeDetectionStrategy.OnPush }) 💻 3. How Do You Implement Route Guards? Answer:Route guards control access to certain routes based on conditions. Angular provides CanActivate, CanDeactivate, Resolve, and CanLoad interfaces. Example: typescript @Injectable() export class AuthGuard implements CanActivate { constructor(private auth: AuthService) {} canActivate(): boolean { return this.auth.isLoggedIn(); } 💻 4.How Do You Manage State in AngularApplications? Answer:State can be managed using: •  Services with BehaviorSubject for simple state •  NgRx or Akita for complex state using Redux-like patterns Example with BehaviorSubject: typescript private userSubject = new BehaviorSubject<User | null>(null); user$ = this.userSubject.asObservable(); setUser(user: User) { this.userSubject.next(user); } 💻 5. How Is Testing Done in Angular? Answer:Angular provides robust testing tools via: •  Karma (test runner) •  Jasmine (test framework) •  TestBed for unit testing components and services Example unit test: typescript it('should create the component', () => { const fixture = TestBed.createComponent(AppComponent); const app = fixture.componentInstance; expect(app).toBeTruthy(); });

Day 52 of My #100DaysFullstackChallenge Today I explored deeper backend architecture concepts in Node.js. Instead of just writing code, I analyzed the strengths and weaknesses of what I built. What I Implemented • A custom HTML template replacement module • Routing using Node’s core http module • JSON-based data rendering • Event-Driven Architecture • A custom class extending EventEmitter • Custom event emission and listeners (Observer Pattern) Advantages I Observed  Modularization (Custom Modules) Improves maintainability, separation of concerns, and reusability.  Event-Driven Architecture Promotes loose coupling — components communicate through events instead of direct dependencies. Extending EventEmitter Makes systems scalable and structured, similar to real-world backend services.  Core HTTP Routing Helps understand how frameworks like Express actually work under the hood. Disadvantages / Trade-offs  Manual string replacement for templating does not scale well compared to template engines like EJS or Handlebars.  Event-driven systems can become difficult to debug if events are emitted in many places.  Writing routing logic with raw http quickly becomes verbose and harder to maintain as applications grow.  EventEmitter is synchronous by default — heavy handlers can block execution. Today wasn’t just about coding — it was about understanding architecture decisions and their consequences. That’s the shift from beginner to backend engineer mindset. On to Day 53. #NodeJS #BackendDevelopment #SoftwareArchitecture #JavaScript #100DaysOfCode

💡 Something Interesting About Node.js Architecture That Many Developers Miss 𝗡𝗼𝗱𝗲.𝗷𝘀 is often called “single-threaded”, but that’s only partially true. Yes, JavaScript in Node.js runs on a 𝘀𝗶𝗻𝗴𝗹𝗲 𝗺𝗮𝗶𝗻 𝘁𝗵𝗿𝗲𝗮𝗱, but Node.js itself is not truly single-threaded. Behind the scenes, Node.js uses l𝗶𝗯𝘂𝘃, which provides a 𝘁𝗵𝗿𝗲𝗮𝗱 𝗽𝗼𝗼𝗹 (usually 4 threads by default). This thread pool handles operations like: • File system operations • DNS lookups • Some cryptographic functions • Compression tasks This means while your JavaScript runs on one thread, certain heavy tasks are 𝗼𝗳𝗳𝗹𝗼𝗮𝗱𝗲𝗱 𝘁𝗼 𝗯𝗮𝗰𝗸𝗴𝗿𝗼𝘂𝗻𝗱 𝘁𝗵𝗿𝗲𝗮𝗱𝘀, allowing Node.js to remain non-blocking. Another interesting thing many developers overlook: 🚀 𝗧𝗵𝗲 𝗘𝘃𝗲𝗻𝘁 𝗟𝗼𝗼𝗽 𝗣𝗵𝗮𝘀𝗲𝘀 𝗺𝗮𝘁𝘁𝗲𝗿 𝗳𝗼𝗿 𝗽𝗲𝗿𝗳𝗼𝗿𝗺𝗮𝗻𝗰𝗲 The event loop processes tasks in phases such as: 1. Timers 2. Pending callbacks 3. Idle/prepare 4. Poll (I/O events) 5. Check (setImmediate) 6. Close callbacks Understanding this explains why sometimes: • `setImmediate()` runs before `setTimeout(fn, 0)` • Certain callbacks behave unexpectedly When building scalable Node.js systems, performance is less about raw computation and more about: ✔ Non-blocking design ✔ Efficient I/O handling ✔ Smart use of queues and background processing Sometimes understanding the 𝗲𝘃𝗲𝗻𝘁 𝗹𝗼𝗼𝗽 improves performance more than rewriting code. #𝗡𝗼𝗱𝗲𝗝𝗦 #𝗕𝗮𝗰𝗸𝗲𝗻𝗱𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 #𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 #𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 #𝗗𝗲𝘃𝗲𝗹𝗼𝗽𝗲𝗿𝘀

When starting a new project with Node.js, I don’t think about Express vs Fastify first. I think about failure, scale, and ownership. After 7+ years building backend systems, here’s what I prioritize before writing the first line of code: 1️⃣ Define the architecture before the routes Monolith or microservices? Modular structure from day one? Clear domain boundaries? If the structure is weak early, refactoring later becomes painful. 2️⃣ Environment & configuration discipline Strict environment variable management No secrets in code Separate configs per environment Centralized logging strategy Production problems usually start with configuration mistakes. 3️⃣ Error handling strategy Most Node.js projects fail here. Centralized error middleware Structured logging (not console.log) Meaningful HTTP status codes Observability hooks (metrics + tracing) If you can’t debug it at 2 AM, it’s not production-ready. 4️⃣ Database decisions early Transaction strategy Index planning Connection pooling Migration versioning Database mistakes are expensive to undo. 5️⃣ Code quality guardrails ESLint + Prettier Folder structure discipline Consistent async handling Avoid callback hell patterns TypeScript whenever possible Node.js gives flexibility. Without discipline, flexibility becomes chaos. Final thought: Node.js is not “just JavaScript on the backend.” It’s a runtime built for concurrency and I/O efficiency. Design for non-blocking behavior from day one. Frameworks are tools. Architecture is responsibility. #NodeJS #BackendEngineering #SoftwareArchitecture #SystemDesign #TechLeadership #APIDesign #ScalableSystems #TypeScript

Angular forms have gone through a major evolution over the years. From template-driven forms to reactive forms, and now toward signal-driven forms. In this article for CODE Magazine, I explore how Angular’s form APIs have evolved and how Signals introduce a new way of thinking about form state, reactivity, and validation. The shift toward signal-driven models could significantly simplify how we build and reason about complex forms. If you're working with Angular or exploring Signals, this deep dive may give you a helpful perspective on where Angular forms are heading. https://lnkd.in/ghGZs7qi #Angular #AngularSignals #WebDevelopment #Frontend

✅ Day 13 — Use Interfaces for API Responses (Angular) Earlier, I was using any for API responses. It worked… until it didn’t. No type safety. No autocomplete. More runtime bugs. So I switched to TypeScript interfaces 👇 ❌ Before (Using any) id="any" getUsers(): Observable<any> { return this.http.get('/api/users'); ❗ No idea what the response contains ❗ Errors found only at runtime ✅ After (Using Interfaces) id="interface" export interface User { id: number; name: string; email: string; } getUsers(): Observable<User[]> { return this.http.get<User[]>('/api/users'); } 🧠 What Changed? IntelliSense / Autocomplete improved ✨ Compile-time error detection 🛡️ Self-documenting API contracts 📄 Cleaner & safer codebase 🎯 Why Interfaces Matter ✅ Prevent accidental property access ✅ Improve developer productivity ✅ Reduce runtime surprises ✅ Make refactoring safer 🧩 Real-World Tip Always place interfaces in: models/ interfaces/ Or alongside feature modules And avoid any unless absolutely necessary. 🧠 Rule I Follow If data comes from an API — it deserves a type. Stronger types = stronger apps 💪 Learning Angular, one good practice at a time 🚀 💬 Do you use interface or type for API models? 👍 Like • Comment • Follow for daily Angular insights #Angular #TypeScript #Interfaces #FrontendDevelopment #CleanCode