DEV Community: Harsh jha

Why Microservices and Why not ?

Harsh jha — Fri, 10 Oct 2025 21:32:53 +0000

As we all know that Microservice is a useful Architecture for the System designing but how much is it dependable.

What Are Microservices?
Microservices architecture divides an application into a collection of small services, each responsible for a specific business functionality. Each service can be developed, deployed, and scaled independently. For instance, in an e-commerce application, you could have separate services for User Management, Payments, Inventory, and Notifications.

Pros

Scalability
Each service can be scaled independently according to demand. For example, a Payment Service experiencing high traffic can be scaled horizontally without affecting other services.
Independent Deployment
Teams can deploy services individually without redeploying the entire application. Using CI/CD pipelines and containerization tools like Docker and Kubernetes, updates can be rolled out faster.
Fault Isolation
A failure in one service does not crash the entire system. Patterns like circuit breakers and retries help prevent cascading failures.
Technology Flexibility
Each microservice can use the most suitable technology stack. For example, Node.js could power your API, Python could handle AI features, and Go could manage high-performance tasks.
Faster Development
Smaller teams can work independently on different services, accelerating development cycles and reducing coordination overhead.
Reusability and Resource Optimization
Services like Authentication or Notification can be reused across multiple applications. Additionally, each service can select the most suitable database or caching system, e.g., MongoDB for User Service and Redis for caching.

Cons

Increased Complexity
Managing multiple services increases system complexity. Distributed tracing tools like OpenTelemetry or Jaeger are often required for debugging and monitoring.
Network Latency
Communication between services over HTTP or gRPC adds overhead and can affect performance.
Data Consistency Challenges
Since each service may maintain its own database, ensuring ACID compliance is harder. Strategies like eventual consistency, Sagas, and distributed transactions are often necessary.
Operational Overhead
Microservices demand sophisticated monitoring, orchestration, and logging. Tools like Kubernetes, Prometheus, and ELK stack become essential.
Testing Difficulties
Integration testing across multiple services can be challenging. Developers often use contract testing and service mocking.
Deployment Coordination
Deploying multiple services simultaneously requires careful version management and backward compatibility planning.
Security Concerns
More services increase the attack surface. Proper authentication between services (e.g., JWT, mTLS) and API gateway enforcement is crucial.

Why Traffic-Heavy Platforms Adopt Microservices and In which Scenario it can fail

Independent Scalability

Each service can scale separately.

Example: On Amazon, the Payment Service can scale to handle spikes without scaling the Search Service.

In a monolith, scaling means replicating the entire app, which is resource-heavy and inefficient.

Fault Isolation

If one service fails (e.g., notifications), it doesn’t crash the whole system.

Circuit breakers, retries, and fallback mechanisms help manage failures gracefully.

Parallel Development & Deployment

Different teams can work on independent services and deploy them without affecting others.

Faster bug fixes and new feature rollouts during high-demand periods.

Optimized Resource Usage

Each microservice can choose its own database, caching, or queue.

For example, caching the most popular products in a microservice reduces DB load during traffic spikes.

Why Microservices Can Fail Under Heavy Traffic

Network Overhead

Microservices talk to each other over the network.

Too many requests → latency builds up → requests can timeout or fail.

Distributed System Complexity

More services → harder to monitor and debug.

A slow dependency can cascade into failures if not handled (hence the need for circuit breakers, rate limiting, timeouts).

Data Consistency Issues

Each service may have its own database.

Heavy traffic can lead to race conditions or eventual consistency issues if not carefully managed.

Orchestration and Deployment Challenges

Spinning up more instances quickly requires orchestration tools like Kubernetes.

Misconfigurations during traffic spikes can cause service unavailability.

How Companies Handle This Risk

Load Balancing & Auto-Scaling
Tools like AWS ALB/ELB, Kubernetes HPA, or NGINX distribute traffic efficiently.
Caching

Redis, Memcached, or CDNs reduce DB and service load.

Circuit Breakers & Retry Policies

Prevent cascading failures (Netflix’s Hystrix is a classic example).

Async Communication

Using message queues like Kafka or RabbitMQ for heavy operations prevents blocking.

Monitoring & Observability

Distributed tracing, Prometheus, Grafana, and alerts detect early issues under traffic spikes.

Conclusion
Microservices architecture offers significant advantages for scalability, deployment flexibility, and team productivity. However, these benefits come with increased complexity, operational overhead, and potential consistency challenges. Organizations adopting microservices must carefully plan infrastructure, monitoring, and communication patterns to fully leverage the architecture’s potential.

When implemented correctly, microservices allow businesses to build resilient, scalable, and maintainable applications that can evolve with changing requirements.

Difference between Client/Browser API and Server-side web API

Harsh jha — Thu, 09 Oct 2025 04:46:14 +0000

API = Application Programming Interface

Definition: A set of rules or methods that allows two software programs to communicate.

Purpose: Let programs talk to each other without knowing the internal details.

Client web API

A Browser Web API is a set of features provided by the web browser that allows JavaScript to interact with the browser environment, the webpage, or the user’s device, beyond what core JavaScript can do. These APIs are built into the browser, so you don’t need to install anything to use them. They extend JavaScript’s capabilities, enabling tasks such as making HTTP requests (fetch()), storing data locally in the browser (localStorage or sessionStorage), manipulating HTML elements via the DOM (document.querySelector), running heavy tasks in background threads (Web Worker), showing desktop notifications (Notification), accessing the user’s location (Geolocation), or enabling real-time communication with the server (WebSocket). Browser Web APIs are primarily client-side, meaning they run in the user’s browser, and they are often used to interact with server-side Web APIs by sending requests and receiving responses. In essence, these APIs are the tools provided by the browser that empower JavaScript to do things it otherwise cannot, such as communicating with servers, storing data, or accessing device features, all while keeping the frontend responsive and interactive.

Server-side web API

A Server-Side Web API is an interface provided by a backend server that allows clients, such as web browsers, mobile apps, or other servers, to communicate with it. Its main purpose is to let clients read, create, update, or delete data stored on the server or in a database. Server-side Web APIs do not provide features to manipulate the client’s interface or access the user’s device; they are purely for communication and data handling. Clients interact with the API by sending HTTP requests—for example, GET to fetch data, POST to create new entries, PUT/PATCH to update existing data, and DELETE to remove data. The server processes these requests, performs necessary operations such as querying a database or executing logic, and responds with structured data, usually in JSON format. Examples include REST API endpoints like /api/contact for submitting a contact form, /api/products for retrieving product data, or public APIs like GitHub API or Stripe API.

Clear difference

Browser (Client-Side) Web APIs are features provided by the browser that let JavaScript interact with the browser environment, the webpage, and the user’s device. They include capabilities like making network requests (fetch()), accessing storage (localStorage), manipulating the DOM (document.querySelector), running background tasks (Web Worker), showing notifications, and accessing device features like geolocation. Besides these capabilities, browser Web APIs also provide the interface for communicating with servers, allowing the frontend to send requests to server-side Web APIs and receive responses.

On the other hand, Server-Side Web APIs do not provide extra features for the client like manipulating the UI or accessing the device. Their purpose is purely to serve as an interface for clients to interact with the server—to read, create, update, or delete data on the server or database. They handle requests coming from clients, process them (e.g., query a database), and send back responses, usually in JSON format. Server-side Web APIs are all about communication and data handling, not providing browser or device-specific capabilities.

Understanding the Modern Web Stack: WebAssembly(WASM), Web Workers, and the V8 Engine

Harsh jha — Wed, 08 Oct 2025 22:31:36 +0000

Modern web applications are no longer just static pages. Today’s web apps need speed, concurrency, and the ability to run complex code efficiently in the browser. Key technologies that enable this are:

WebAssembly (Wasm) – Runs near-native performance code in browsers.

Web Workers – Allow background threads to run heavy tasks without freezing the UI.

V8 Engine – The JavaScript engine powering Chrome and Node.js, enabling JIT compilation and high performance.
1. WebAssembly (Wasm)

What is Wasm?

A binary instruction format for the web.
Designed for high-performance execution, almost like running native code.
Typically compiled from languages like C, C++, or Rust.

Why Wasm?

JavaScript alone can be slow for CPU-intensive tasks.
Wasm enables heavy computations, games, image/video processing, and scientific simulations to run efficiently in the browser.

How it works

Write code in a language like C/C++/Rust.
Compile it to a .wasm file.
Load it in JavaScript using the WebAssembly API.
Execute functions from JS, optionally interacting with the DOM.

2. Web Workers

What are Web Workers?

A browser feature that allows JavaScript code to run in a separate thread.
Prevents UI from freezing when performing heavy computations.

Types of Web Workers

Dedicated Workers – For a single script.
Shared Workers – Can be shared across multiple scripts/tabs.
Service Workers – Intercept network requests and enable offline capabilities.

How Web Workers help Wasm

Wasm modules can be run inside a Web Worker, so computationally heavy tasks don’t block the main thread.

Example: Running video encoding or AI inference in the background.

3. V8 Engine

What is V8?

The JavaScript engine developed by Google for Chrome and Node.js.
Compiles JS to machine code using JIT (Just-In-Time) compilation, giving near-native performance.

Role in WebAssembly

V8 also supports Wasm execution.
Converts .wasm bytecode to machine code and optimizes execution.
Works seamlessly with JS, allowing JS↔Wasm interop
.

4. How They Work Together

Code Preparation:

Write computational code in C++/Rust → Compile to Wasm.

Loading Wasm in Browser:

JS fetches the .wasm file.

V8 engine compiles Wasm to machine code.

Offloading Heavy Tasks:

Use Web Workers to run Wasm modules in the background.

Main UI thread remains responsive.

Interop:

JS can call Wasm functions and vice versa.

Shared memory (via SharedArrayBuffer) allows fast communication between JS and Wasm in workers.

5. Real-World Use Cases

Gaming in the Browser: Unity or Unreal Engine exporting to WebAssembly.
Video & Image Processing: FFMPEG compiled to Wasm for in-browser transcoding.
Machine Learning: TensorFlow.js or ONNX running models with Wasm backend.
Cryptography & Compression: Running CPU-heavy tasks in the browser safely.

Conclusion

The modern web stack is evolving to bring near-native performance to browsers.

WebAssembly handles heavy computation.
Web Workers ensure non-blocking, concurrent execution.
V8 Engine powers both JS and Wasm efficiently.

Together, they allow developers to build fast, responsive, and complex web applications, blurring the line between native and web apps.