DEV Community: Deepak Sen (Web Developer)

Practical Guide to Caching and Performance Optimization

Deepak Sen (Web Developer) — Tue, 31 Mar 2026 12:01:24 +0000

Caching Documentation

Introduction

Caching is a technique used to store the result of expensive operations so that future requests can be served faster. It is commonly used in web applications to reduce latency, minimize server load, and improve overall performance.

What is `use cache`

The use cache directive allows developers to cache the return value of asynchronous functions and components. When applied, the function or component does not re-execute if the same inputs are provided. Instead, the cached result is returned.

Usage

1. Data-Level Caching

Data-level caching is used for functions that fetch or compute data.

async function getProducts() {
  "use cache";
  // fetch products
}

async function getUser(id) {
  "use cache";
  // fetch user data
}

This approach is useful when the same data is requested multiple times, as it avoids repeated API or database calls.

2. UI-Level Caching

UI-level caching is applied to entire components or pages.

export default async function BlogPage() {
  "use cache";
  // render content
}

This is beneficial for pages that do not change frequently or depend on stable data.

How Caching Works

Caching is based on a cache key that is automatically generated. The key includes:
Function arguments
Variables captured from the surrounding scope
If the same inputs are provided, the cached result is returned. If the inputs change, a new cache entry is created.

Caching Overview

Key Characteristics

Caching is input-dependent
Different inputs produce different cached results
Supports dynamic and parameterized data
Works with both functions and components

Constraints

Only serializable data can be cached
Non-deterministic values (e.g., random numbers, timestamps) should be avoided
Inputs must remain stable for consistent caching behavior

Benefits

Reduces repeated computations
Improves response time
Decreases API and database load
Enhances scalability of applications

Best Practices

Use caching for frequently requested data
Avoid caching highly dynamic or real-time data
Ensure proper data structure and serialization
Monitor cache usage and invalidation strategies if applicable

Conclusion

Caching is an essential optimization technique in modern application development. The use cache directive provides a simple and effective way to implement caching at both data and UI levels. When used correctly, it significantly improves performance and efficiency.

Learn about Production Ready TAILWIND CSS Setup in REACT NATIVE !

Deepak Sen (Web Developer) — Fri, 28 Nov 2025 16:58:05 +0000

Learn about Production Ready TAILWIND CSS Setup in REACT NATIVE !

First you need to setup your react native project ,

Step 1

create the new React Native Project Using Expo
cmd :- npx create-expo-app@latest my-awesome-app
cmd :- cd my-awesome-app

Step 2

Reset your project
You can remove the boilerplate code and start fresh with a new project. Run the following command to reset your project:
cmd : npm run reset-project

Step 3

Install these all package for install Nativewind
cmd:npm install nativewind react-native-reanimated@~3.17.4 react-native-safe-area-context@5.4.0
npm install --dev tailwindcss@^3.4.17 prettier-plugin- tailwindcss@^0.5.11

Step 4

Setup the Tailwind CSS in project
Run npx tailwindcss init to create a tailwind.config.js file
**
/ @type {import('tailwindcss').Config} /
module.exports = {
// NOTE: Update this to include the paths to all files that contain Nativewind classes.
content: ["./App.tsx", "./components//.{js,jsx,ts,tsx}"],
presets: [require("nativewind/preset")],
theme: {
extend: {},
},
plugins: [],
}

Step 5

Add the globals.css file on app folder
globals.css

@tailwind base; @tailwind components; @tailwind utilities;

Step 6

Last Step
npx expo customize metro.config.js

Copy this and replace it
`const { getDefaultConfig } = require("expo/metro-config");
const { withNativeWind } = require('nativewind/metro');

const config = getDefaultConfig(__dirname)

module.exports = withNativeWind(config, { input: './global.css' })`

If Using AS PRODUCTION READY

/** @type {import('tailwindcss').Config} */ module.exports = { // NOTE: Update this to include the paths to all files that contain Nativewind classes. content: ["./app/**/*.{js,jsx,ts,tsx}"], presets: [require("nativewind/preset")], theme: { extend: { colors:{ primary:'#030014', secondary:'#151320', light:{ 100:"#2a2640" } } }, }, plugins: [], }

This Thing help you to play with tailwind Production level

IaaS vs PaaS vs SaaS — The Cloud Models Every Developer Should Understand 📊

Deepak Sen (Web Developer) — Sun, 02 Nov 2025 05:29:47 +0000

☁️ IaaS vs PaaS vs SaaS — The Cloud Models Every Developer Should Understand

Cloud computing has completely changed the way we build, deploy, and scale applications. Instead of worrying about setting up servers in a data center, we now just… click a few buttons.

But not all clouds are created equal. When you hear people talk about IaaS, PaaS, and SaaS, they’re referring to different levels of cloud service models.

Let’s unpack them one by one — in plain developer terms 👇

🏗️ Infrastructure as a Service (IaaS)

IaaS gives you the basic building blocks: virtual machines, storage, and networking.

You manage the operating system, middleware, and runtime — the provider just gives you the infrastructure to run it on.

Think of it as renting a server in someone else’s data center.

Common providers:

AWS EC2
Google Compute Engine
Microsoft Azure

Use case example:

You’re building a custom backend API and need full control over your OS, libraries, and configurations. Spin up a VM on AWS, deploy, and scale when needed.

Pros:

✅ Full control

✅ Pay-as-you-go

✅ Scalable and flexible

Cons:

⚙️ You handle maintenance and updates

🧠 Requires deep technical setup

⚙️ Platform as a Service (PaaS)

PaaS takes away most of the infrastructure pain.

It provides a managed environment to build, test, and deploy your apps — without touching the underlying servers.

Think of it as a pre-configured playground for developers.

Examples:

Heroku
Google App Engine
Render
Vercel (for frontend hosting)

Use case example:

You’re building a Node.js or Python app — just push your code, and the platform handles deployment, scaling, and load balancing automatically.

Pros:

🚀 Super fast setup

💻 Focus on writing code

☁️ Auto scaling built-in

Cons:

🔒 Less control over configurations

💰 Can get expensive at scale

💻 Software as a Service (SaaS)

SaaS is the top layer — you don’t build or host anything. You just use the software via a web app or API.

Think of it as renting a fully finished apartment. Just move in and start living.

Examples:

Notion
Slack
Google Workspace
Zoom

Use case example:

Your team uses Slack for communication or Notion for documentation. You don’t care how it’s hosted — you just use it daily.

Pros:

✅ No installation or maintenance

✅ Access anywhere

✅ Always updated

Cons:

🔐 Limited customization

🌍 Fully dependent on provider uptime

🔄 How They Work Together

Let’s say you’re running a SaaS startup:

You host your backend on AWS EC2 → IaaS
You deploy your app through Heroku → PaaS
Your clients use your web app → SaaS

That’s the beauty of the cloud — layers working together to simplify complex problems.

🚀 Wrapping Up

Whether you’re deploying your first app or scaling to a million users, knowing how IaaS, PaaS, and SaaS differ helps you make smarter technical and business decisions.

Each has its trade-offs — control vs convenience, flexibility vs simplicity — but all three are part of what makes the cloud so powerful.

💬 What’s your go-to stack?

Do you prefer managing your own infra or just shipping with Heroku/Vercel and forgetting about it?

Drop your thoughts below 👇

#cloudcomputing #devops #developers #saas #paas #iaas #webdev #programming #DiCoTr

Copy On Write (CoW) Explaination in OS and Docker

Deepak Sen (Web Developer) — Sun, 28 Sep 2025 08:26:45 +0000

CoW stands for (Copy On Write) in OS

CoW is Use for Memory management and optimization For New GEN Modern OS
Instead of creating a full copy of a resources (Memory ,CPU , Page) The OS delays copying until data is actually modified in (Written)

How it works on OS

When you fork a process in Linux or Unix :
- Parents and child Process Initially Share the same physical resource
- Pages are as read-only
When either process Tries to write to a shared pages
- Os Creates a Private copy of that page for the writing process
- Save the Ram and Speed !

Benifits

Reduce memory usage
Speed Up process creation.
Allow LightWeight Snapshot data

Copy On Write in Docker
Docker utilizes a copy-on-write (CoW) strategy for efficient storage management and performance optimization, particularly with image layers and containers. This mechanism is central to how Docker shares and manages file system changes.

how it works:

Image Layers: Docker images are composed of multiple read-only layers. When you build an image, each instruction in your Dockerfile creates a new layer on top of the previous one. These layers are shared across multiple images if they have common base layers, saving disk space.
Container Writable Layer:When you run a container from an image, Docker adds a thin, writable layer on top of the image's read-only layers. All changes made within the running container occur in this writable layer.

CoW Actions:

If a process inside a container needs to read a file, it accesses the file directly from the lower, read-only layers if it exists there.
If a process needs to modify a file that exists in a lower, read-only layer, Docker does not modify the original file. Instead, it copies that file from the read-only layer into the container's writable layer.

Benefits of Copy-on-Write

Efficient Storage
Fast Container Startup
Isolation

Written by Deepak Sen

DiCotr

Life Cycle React of functional Programming

Deepak Sen (Web Developer) — Sat, 20 Sep 2025 16:13:58 +0000

*Life Cycle React of functional Programming**

Just we talk about types of component generally in react .so We have:-
Functional Component -> a simple components hooks or state
Class Component -> using this.state and components

A Lifecycle of functional programming in react - Each component in react have lifecycle in three phases are mounting ,updating,unmounting.

Mounting Phase
--> Mounting phase is occurs when functional components are initially load in render and add to DOM

useState -> it is a initial component state

useEffect->it call the function and empty array dependency

for class Components-> componentDidMount

import {useState ,useEffect} from 'react
const App =()=>{

const [val , setval]=useState(0)
useEffect(()=>{
console.log(val)
},[])
return(
      <>
       <h1>updated value ----- {val}</h1>
       <button onClick={()=>setval(val+1)}>Increase</button>
      </>
        ) 

}

Updating Phase
useState: The setter function returned by useState (setCount in the example above) triggers a re-render when called, updating the component's state.

useEffect- without an empty dependency array (or with specific dependencies): Simulates componentDidUpdate. The effect function runs after every render where the specified dependencies have changed. If no dependency array is provided, it runs after every render. This is used for side effects that need to react to changes in state or props.

  import React, { useState, useEffect } from 'react';

    const App=()=> {
      const [val, setval] = useState(0);

      useEffect(() => {
        console.log('Component updated!'); // Runs on every re-render
      });

      useEffect(() => {
        console.log('Value changed:', val); // Runs when val changes
      }, [val]); // Dependency array with val

      return (
        <div>
          <p>value is ---- {val}</p>
          <button onClick={()=> setval(val + 1)}>Increment</button>  

          <p>Value: {val}</p>

        </div>
      );
    }

Unmounting Phase
this phase occurs when the component is removed from the DOM.

    import React, { useEffect } from 'react';

    const App=()=> {
      useEffect(() => {
        console.log('Component mounted!');
        const timer = setInterval(() => console.log('Timer running..'), 1000);

        return () => {
          console.log('Component unmounted!'); // Cleanup 
          clearInterval(timer); // Clear  interval
        };
      }, []);

      return <div>My Component</div>;
    }

functional components in React manage their lifecycle through the strategic use of

useState for state management and useEffect for handling side effects and cleanup, effectively replicating the lifecycle phases found in class components.

By Deepak sen
for contact
care.deepaksen@gmail.com