If you run a coaching centre, local business, or startup, you probably care about enrollments, orders, trust, and speed—not framework names. I design and build web and mobile experiences that support those goals, using React, React Native, Node, Firebase, and the MERN stack when they are the right fit. Below is my formal background and depth for teams that need it.
Sr. Software Developer — Experienced in mobile and web development across IT and services. Skilled in React Native, JavaScript, React, Next.js, Flutter, Solidity, blockchain, MySQL, PHP. B.Tech. (Computer Technology) from Bhagalpur College of Engineering.
Summary
Description: Learn key Blockchain concepts, intuition, and practical training to get you
quickly up to speed with all things Crypto and blockchain-related.
Issued: July 2023
Certification ID: UC-bdff91c8-1543-432e-90ca-bidaa75bcad3
Description: Ethereum and Blockchain technology is the most disruptive force in years.
Companies cannot hire developers who understand blockchain technologies fast enough, but there are a
tiny number of resources published to help you truly understand what blockchains are used for, let
alone build apps with them. That's the purpose of this course: to be the best resource online for
learning about Ethereum, blockchains, and how to build apps with this new technology. The
development community is still figuring out the best way to use Ethereum in the creation of new and
exciting apps. I spent a tremendous amount of time to research and create best practice for
interfacing with Ethereum from Javascript.
Issued: December 2022
Certification ID: UC-4c080bab-7a0e-4ab6-8236-7fbe5949c490
5+ years of experience as Web Developer. Experience of Interacting with the Client & Understanding requirements. Experience of Designing the layout, UI while achieving Customer/user Friendliness.
Created Reusable react presentation and container components. Good understanding and usage of states and props. Implemented EcmaScript6 (ES6) arrow functions, constants, block-scope variables, class inheritance.
Focused help for coaching institutes, local brands, and startups—you get outcomes and timelines, not buzzwords.
Course pages, student portals, test flows, and admin tools that reduce phone chaos and make enrollment and content easier to manage.
From idea to launch: flows that match how users actually behave, MERN or Firebase backends, and code your next hire can extend.
Pixel-faithful UI, mobile-first layouts, and components wired to your APIs—so marketing and product stay aligned.
Performance work, refactors, and hard debugging so customers stop bouncing and your team stops firefighting.
REST APIs, MongoDB/Node services, Firebase, payments, and deployment choices that match your scale and budget.
Build Mobile Application with React native and Integrate API.
Worked on code Spilitting and use Resuable Componants
Understand Flutter concepts and Create open chat Application using firebase
Integrate Video Chat Application using WebRTC
Working on Widgets and Plugin Integration.
Build Mobile Application with React native.
Involved in Various Projects Ecommerce and worked on all the Devices.
Mananging and Uploading Application form App-store and Play-store
Experience in Cross-Platform Mobile Development using
React Native + Redux based mobile app
Used React concepts like JSX (JavaScript Syntax
Extension), components, state and props.
Building reusable components and front-end libraries for future use.
Creating User Interface using React native Paper.
Integrating API in React Native app.
Build websites using VueJs and NextJs.
activity involved with client meetings.
Design new features for existing websites.
Developing and creating PHP MySQL applications as per
the specifications.
Troubleshot problems with PHP and other web
technologies.
Screenshots below show breadth; for what changed for the business (problem → outcome), see Case Studies—that is what hiring clients read first.
Each card is written for buyers: the business problem, what shipped, and the result—plus a live or store link when it is public. Search by niche (e.g. coaching, retail, health) or stack.
Ready when you are: new site, app, or rescue job. Start with a free 15-minute call—no obligation.
Sanjeev delivered a clean and scalable solution. Highly recommended for React and full-stack projects.
Our institute needed more than a template site—batches, content, and inquiries in one flow. He shipped fast and explained trade-offs in simple terms.
Strong communication, fast iterations, and production-quality code. He understood our business goals, not just the tickets.
He fixed performance issues we had ignored for months. The app finally feels like something we can show investors.
Milestones you can plan around, with visible progress—not endless back-and-forth.
Readable structure and patterns so the next developer (or you) can ship without fear.
Plain-language updates, honest timelines, and proactive questions before blockers hurt the schedule.
From UI polish to APIs and deployment—I can own the slice of the stack you need.
Final quotes depend on scope. These ranges help serious clients self-filter before we talk.
Landing pages, coaching or local business sites, lead forms, Firebase or static hosting.
Dashboards, authenticated apps, integrations—scope-dependent.
MVPs, multi-role apps, mobile + web, or ongoing monthly support.
Tell me about your product or bottleneck. I will tell you honestly if I am a fit—and what I would tackle first.
Bonus: Ask for a quick website or app audit (high-level, no fluff) when you reach out.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
contract Web3Amazon {
address public owner;
struct Product {
uint256 ID;
string name;
string image;
uint256 price;
uint256 rating;
uint256 stock;
}
mapping(uint256=>Product) public products;
struct Order {
uint time;
Product product;
}
mapping(address=>uint256) public orderCount;
mapping(address=>mapping(uint256=>Order)) public orders;
event List(string name, uint256 price, uint256 quantity);
event Buy(address buyer, uint256 orderID, uint256 productID);
constructor() {
owner = msg.sender;
}
modifier onlyOwner {
require(msg.sender == owner, "You don't have access to List Products!");
_;
}
modifier checkStock(uint256 _stock) {
require(_stock > 0, "Product is Out Of Stock!");
_;
}
function listProduct(
uint256 _ID,
string memory _name,
string memory _image,
uint256 _price,
uint256 _rating,
uint256 _stock
) public onlyOwner {
products[_ID] = Product(_ID, _name, _image, _price, _rating, _stock);
emit List(_name, _price, _stock);
}
function buyProduct(uint256 _ID) public payable {
Product memory product = products[_ID];
require(msg.value >= product.price, "Product is Out Of Stock!");
require(product.stock > 0, "Product is Out Of Stock!");
Order memory order = Order(block.timestamp, product);
orderCount[msg.sender]++;
orders[msg.sender][orderCount[msg.sender]] = order;
products[_ID].stock = product.stock - 1;
emit Buy(msg.sender, orderCount[msg.sender], _ID);
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
contract Election {
struct Candidate {
uint id;
string name;
uint voteCount;
}
mapping(address=>bool) voters;
mapping(uint=>Candidate) public candidate;
uint public candidateCount = 0;
constructor() {
addCandiate("BJP");
addCandiate("Congress");
}
modifier verifyVoters() {
require(!voters[msg.sender], "You have alreday done process of voating!!");
_;
}
function addCandiate(string memory _name) private {
candidateCount++;
candidate[candidateCount] = Candidate(candidateCount, _name, 0);
}
function vote(uint _candidateId) public verifyVoters {
voters[msg.sender] = true;
candidate[_candidateId].voteCount++;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.8;
contract Hotel {
enum Status { Occupied, Vacent }
Status currentStatus;
address public owner;
constructor() {
owner = msg.sender;
currentStatus = Status.Vacent;
}
modifier roomStatusModifier() {
require(currentStatus == Status.Vacent, "Already Occupied!");
_;
}
modifier paymentStatusModifier() {
require(msg.value > 0.01 ether, "You do not have enfough money!!");
_;
}
receive() external payable roomStatusModifier paymentStatusModifier {
payable(owner).transfer(msg.value);
currentStatus = Status.Occupied;
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.8;
contract Upload {
struct Access {
address user;
bool access;
}
mapping(address=>string[]) value;
mapping(address=>mapping(address=>bool)) ownership;
mapping(address=>Access[]) accessList;
mapping(address=>mapping(address=>bool)) previousData;
function add(address _user, string memory url) external {
value[_user].push(url);
}
function allow(address user) external {
ownership[msg.sender][user] = true;
if(previousData[msg.sender][user]) {
for(uint i=0;i < accessList[msg.sender].length; i++) {
if(accessList[msg.sender][i].user == user) {
accessList[msg.sender][i].access = true;
}
}
} else {
accessList[msg.sender].push(Access(user, true));
previousData[msg.sender][user] = true;
}
}
function disallow(address user) public {
ownership[msg.sender][user] = false;
for(uint i=0;i < accessList[msg.sender].length; i++) {
if(accessList[msg.sender][i].user == user) {
accessList[msg.sender][i].access = false;
}
}
}
function display(address _user) external view returns(string[] memory) {
require( _user == msg.sender || ownership[_user][msg.sender], "You don't hace access");
return value[_user];
}
function shareAccess() public view returns(Access[] memory) {
return accessList[msg.sender];
}
}
PriceConvertor.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
library PriceConvertor {
function getPrice() internal view returns(uint) {
// ABI
// Address 0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e
AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
(,int price, , ,)=priceFeed.latestRoundData();
return uint(price*1e10);
}
function priceConversionRate(uint ethAmount) internal view returns(uint) {
uint ethPrice = getPrice();
// 3000_000000000000000000 = ETH / USD Price
// 1_000000000000000000 = ETH
uint ethPriceInUsd = ( ethAmount * ethPrice ) / 1e18;
return ethPriceInUsd;
}
function getVersion() internal view returns(uint) {
AggregatorV3Interface priceFeed = AggregatorV3Interface(0xD4a33860578De61DBAbDc8BFdb98FD742fA7028e);
return priceFeed.version();
}
}
FundMe.sol
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import './PriceConvertor.sol';
contract FundMe {
using PriceConvertor for uint;
uint public mimimumUsd = 10 * 1e18; // 1000000000000000000 ETH
address[] public funders;
mapping(address=>uint) public funderAddressToPrice;
address public owner;
constructor() {
owner = msg.sender;
}
function fund() public payable {
// want to send minimum USD for fund
// require(priceConversionRate(msg.value) > mimimumUsd, "don't have enfough amount");
// with library we need to call something like below
// require(priceConversionRate(msg.value) > mimimumUsd, "don't have enfough amount"); // or
require(msg.value.priceConversionRate() > mimimumUsd, "don't have enfough amount"); // here bydefault msg.value is first paramter if we need to send second Params use msg.value.priceConversionRate(234)
funders.push(msg.sender);
funderAddressToPrice[msg.sender] = msg.value;
}
function withdraw() public _onlyOwner {
for(uint fundIndex = 0; fundIndex < funders.length; fundIndex++) {
address funder = funders[fundIndex];
funderAddressToPrice[funder] = 0;
}
funders = new address[](0);
(bool callSuccess, ) = payable(msg.sender).call{ value : address(this).balance}("");
require(callSuccess, "Transfer Failed");
}
modifier _onlyOwner() {
require(owner == msg.sender, "Your are not owner!");
_;
}
receive() external payable {
fund();
}
fallback() external payable {
fund();
}
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.7;
contract Donation {
address owner;
uint balance;
bool isDiseases;
constructor() payable {
owner = msg.sender;
balance = msg.value;
isDiseases = false;
}
address payable[] walletAddress;
mapping(address => uint) inheritance;
modifier onlyOwner() {
require(owner == msg.sender, "You don't have access to Set Inheritance!!");
_;
}
modifier verifyDiseases() {
require(isDiseases == true, "You don't have any Diseases!!");
_;
}
function setInheritance(address payable _walletAddress, uint _amount) public onlyOwner{
walletAddress.push(_walletAddress);
inheritance[_walletAddress] = _amount;
}
function payout() private verifyDiseases {
for(uint i=0; i < walletAddress.length; i++) {
walletAddress[i].transfer(inheritance[walletAddress[i]]);
}
}
function hasDiseases() public onlyOwner {
isDiseases = true;
payout();
}
}
Tell me what you are trying to achieve—more students, more orders, or a stable product—and I will reply with next steps. Coaching institutes, local brands, and startups welcome. MERN, React Native, Firebase, integrations. India & remote.
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