Swapnil Patil, Developer in Pune, Maharashtra, India
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Swapnil Patil

Bio

Swapnil has over ten years of experience working with Fortune 500 companies and infant-stage startups, including three years of remote work. He is experienced in building high-performing reusable components and responsive, accessible, scalable, and secure single-page web applications from scratch. He has worked on refactoring legacy codebase and improving application performance. Swapnil's been freelancing remotely on three continents, successfully managing multiple time zones.

Portfolio

Cybersecurity Platform
React, Redux, JavaScript, TypeScript, HTML5, CSS3, Material UI, Webpack 4...
Analytics Platform
React, Redux, CSS3, FusionCharts, Figma, Front-end, Front-end Development...
Noissue
React, Gatsby, Next.js, Contentful, CSS3, SCSS, Tailwind CSS, Webpack 3...

Experience

  • JavaScript - 8 years
  • ECMAScript (ES6) - 6 years
  • React - 5 years
  • Webpack - 4 years
  • ES7 - 4 years
  • React Redux - 4 years
  • Redux - 4 years
  • TypeScript - 2 years

Preferred Environment

Slack, Visual Studio Code (VS Code), React, UI Development, JavaScript, Redux, ES7, ECMAScript (ES6)

The most amazing...

...thing I've developed was a payment integration with Western Union that is used to transfer money by millions of people around the world.

Work Experience

Lead Front-end Engineer

2022 - PRESENT
Cybersecurity Platform
  • Led the design and implementation of scalable, performant, and accessible front-end applications within a complex cybersecurity platform ecosystem, reducing page load times by 35%.
  • Designed and reprocessed event pools, increasing the throughput of real-time threat detection pipelines by 40% and reducing false-positive alerts by 25% through improved data correlation accuracy.
  • Architected and optimized a natural language query builder using ANTLR, improving analyst query speed by 60% and reducing support tickets related to query syntax issues by 30%.
  • Contributed to securing client-server communication by implementing JWT-based authentication flows in front-end applications.
  • Integrated 40+ reusable React components and enhanced micro front-end architecture, boosting feature delivery by 50%, reducing build times by 25%, and enabling modular, parallel development across teams.
  • Participated in containerizing front-end applications using Docker and automated deployments through CI/CD pipelines using GitHub Actions and Argo CD, ensuring consistent and reliable delivery to Kubernetes environments.
  • Developed and architected a correlation rules builder for a cybersecurity alert application (SIEM), integrating MITRE ATT&CK mapping to enhance rule context and visibility.
  • Spearheaded event reprocessing pipelines and optimized data import/export using batching and throttling, reducing latency by 60% and supporting real-time ingestion of millions of events per day.
  • Followed OWASP best practices during front-end development by validating user inputs, sanitizing outputs, and preventing common vulnerabilities.
Technologies: React, Redux, JavaScript, TypeScript, HTML5, CSS3, Material UI, Webpack 4, Microfrontends, MUI CSS, UI Design, Web Design, Site Speed Optimization

Senior UI Engineer

2019 - 2022
Analytics Platform
  • Led the design and development of a micro front-end architecture for the Aera Platform, integrating 5+ core modules (Analytical Platform, Skill Developer, Process Builder, Workbench, and Decision Platform), and reducing deployment dependencies by 40%.
  • Identified web-based user interactions and developed highly responsive UI components using React, contributing to a 20% improvement in user engagement across core modules.
  • Developed modern, user-facing features using React and built a reusable component library, published as an internal npm package, reducing duplicate code across teams by 35%.
  • Built internal tooling and mock API servers using Node.js and Express.js to simulate back-end responses during local UI development and component testing.
  • Monitored and improved front-end performance by 15%, documented application changes, and worked on the updates.
  • Used Express.js middleware for mocking authentication and routing logic, improving testability and reducing frontend-blocking issues during early development phases.
  • Monitored and improved front-end performance by 15%, using Lighthouse audits and real-user monitoring tools to guide optimizations across critical user journeys.
  • Utilized modern front-end build tools such as Webpack, Babel, and npm/yarn to improve code bundling, tree-shaking, and dependency management across micro frontends.
  • Wrote 100+ unit test cases using React Testing Library and Jest, achieving 75%+ code coverage and reducing UI regression issues by 40%.
  • Integrated both RESTful and GraphQL APIs into React applications, improving data handling efficiency and reducing overfetching on critical user interfaces.
Technologies: React, Redux, CSS3, FusionCharts, Figma, Front-end, Front-end Development, GitHub, Git, Webpack, React Redux, Lodash, Web Development, JavaScript 6, Communication, ECMAScript (ES6), Jira, User Interface (UI), JavaScript, APIs, HTML, CSS, Vanilla JS, Teamwork, Visual Studio Code (VS Code), Software as a Service (SaaS), MacOS, Slack, Information Technology, Management, ES7, SCSS, UI Development, Algorithms, JSON, Responsive, Responsive Design, Web UI, Web UX, Dashboards, Data Visualization, Web Dashboards, Material UI, Axios, React Query, MUI CSS, UI Design, Web Design, AI Tools, Site Speed Optimization

Senior Software Engineer

2021 - 2021
Noissue
  • Developed a community module for the project and reusable React components for the module.
  • Tracked and fixed bugs using Jira as a reporting tool.
  • Handled website loading time, managing image and asset loading time.
  • Shared each functionality with stakeholders. Provided my suggestions on functionality and resolved feedback from stakeholders and peers.
Technologies: React, Gatsby, Next.js, Contentful, CSS3, SCSS, Tailwind CSS, Webpack 3, GraphQL, GitHub, Jira, Asana, JavaScript 6, React Redux, Responsive UI, Web Development, TypeScript, Communication, Slack, Lodash, APIs, Responsive, React-Bootstrap, Responsive Web Design (RWD), HTML, CSS, Vanilla JS, Teamwork, eCommerce, Less, Software as a Service (SaaS), MacOS, Information Technology, JavaScript, User Interface (UI), ES7, ECMAScript (ES6), Webpack, Figma, Front-end Development, Visual Studio Code (VS Code), UI Development, JSON, Redux, Responsive Design, Web UI, Web UX, Material UI, Axios, UI Design, Web Design

Senior Software Engineer

2018 - 2019
Western Union
  • Designed and coded application components in an agile environment, utilizing a test-driven development approach.
  • Cooperated closely with project managers, product owners, and other functional team members to form a team effort in development.
  • Took responsibility for estimating efforts to implement user stories, plan sprints, prioritize the sprint backlog, manage all the tasks, and report on progress.
  • Identified potential obstacles and recommended alternative solutions to team members and a scrum master.
  • Used Scrum for agile development and participated in team-led solutions, reviewing peers' code for quality and completeness.
  • Collaborated closely with all other team members to take shared responsibility for the overall efforts that the team has committed to.
  • Handled a team of five resources and contributed to production-iteration planning.
Technologies: React, AngularJS, CSS3, Grunt, Gulp, JavaScript, ECMAScript (ES6), Web Development, Fintech, Fintech Consultant, Finance, React Redux, Redux, User Interface (UI), Front-end Development, Responsive UI, Git, GitHub, Communication, Lodash, CSS, Front-end, Express.js, Responsive, Responsive Web Design (RWD), HTML, Vanilla JS, MacOS, Slack, Information Technology, ES7, Webpack, Figma, Visual Studio Code (VS Code), Jira, UI Development, Software as a Service (SaaS), JavaScript 6, JSON, Mobile App Development, Axios, UI Design, Web Design

Senior Software Engineer

2017 - 2018
Globant
  • Communicated with the client to gather requirements for sprint and created stories and subtasks with time estimation.
  • Developed a generic Lego component using the AngularJS framework.
  • Automated unit testing for the component unit testing.
  • Contributed to unit test cases development, testing, debugging, and defect fixing.
  • Produced estimations by evaluating instructions, specifications, and discussions with the onsite coordinator.
Technologies: Angular, AngularJS, PrimeNG, Grunt, Webpack, CSS3, ECMAScript (ES6), React, React Redux, Responsive UI, User Interface (UI), ES7, Front-end, Web Development, Lodash, JSON, Communication, SCSS, TypeScript, Git, GitHub, Bootstrap, Responsive, HTML, CSS, Vanilla JS, Visual Studio Code (VS Code), MongoDB, Bootstrap 3, Node.js, Less, Information Technology, JavaScript, Front-end Development, Fintech, Jira, UI Development, Data Visualization, Dashboards, UI Design, Web Design

Consultant

2015 - 2017
Capgemini India
  • Communicated with the client regarding the feasibility of a new finance project requirement in functional HTML. Worked on design changes, bug fixing, and adding functionality.
  • Created and added Dojo functionality to web pages to create interactive forms.
  • Developed accessibility for web pages as per Web Content Accessibility Guidelines (WCAG).
  • Trained and guided team members on the current UI standards.
  • Contributed to the responsive design of the websites, making them compatible with all small-screen devices.
  • Handled cross-browser issues and provided fixes.
Technologies: JavaScript, CSS3, Finance, Fintech, Fintech Consultant, User Interface (UI), Front-end, Front-end Development, Web Development, Lodash, JSON, Git, GitHub, Communication, Online Banking, Visual Studio Code (VS Code), Vanilla JS, Bootstrap 3, Information Technology, HTML, CSS, Jira, UI Development, Bootstrap, Web Design

Software Engineer

2013 - 2015
Cybage
  • Created different new and standalone pages using HTML, CSS, jQuery, and AngularJS.
  • Converted the complete product from table structure to div structure in HTML.
  • Made a non-responsive site responsive with the help of a UI designer. Worked on cross-browser compatibility issues.
  • Conducted requirement and design analysis and coordinated with team members for test planning and scheduling.
  • Contributed to the project's development phase, which included the user interface, admin functionality, and SEM creations.
  • Tested the cross-browser compatibility and fixed the detected issues per business requirements.
Technologies: JavaScript, HTML, CSS, Information Technology, User Interface (UI), CSS3, Front-end Development, Web Development, UI Development

Experience

Noissue (via Toptal)

https://noissue.co/
Noissue is an organization that allows you to design your own branded tissue paper and have it shipped to you anywhere in the world. Noissue provides reusable, recyclable, and compostable products with the eco-packaging alliance.

It is an online tool where clients can create their designs for required packaging with quantities. Noissue also provides vast community pages to connect with environment-friendly people.

Detection Management

The project focused on building and optimizing a scalable rule engine and management interface to detect, correlate, and respond to potential security threats in real time. The system enables security analysts to define, manage, and fine-tune correlation rules that identify suspicious activities by analyzing large volumes of event and user behavior data.

Key objectives:
• Develop a flexible correlation rules framework for detecting complex attack patterns (multi-event, sequence-based, and threshold rules).
• Provide a management console for creating, editing, testing, and deploying detection rules.
• Ensure real-time processing and high performance for threat detection at scale.
• Deliver a user-friendly UI for SOC teams to prioritize, investigate, and respond to alerts efficiently.

Core features:
• Rule authoring and testing: Analysts can write correlation rules using predefined templates or custom logic.
• Rule execution engine: Optimized to handle millions of events per day with low latency.
• Threat detection dashboard: Provides visibility into triggered rules, severity levels, and incident timelines.
• Integration: Connects with log sources, identity providers, and case management systems.

Analytics Platform

An analytics platform to track the clients' supply chain management. The project involves analyzing the company's past performance, forecasting business outcomes, and providing results using analytics, graphs, charts, and pivot tables.

I created reusable plug-and-play React and analytics components using third-party tools such as AG Grid and FusionCharts. I have identified potential obstacles and recommended alternative solutions. I collaborated closely with the PO and PM for client requirement gathering and developing technical components.

EXL LifePro

EXL is a US-based insurance company, and LifePro is a web product based on an existing EXL desktop application. EXL wanted to transform in terms of technology and move on the internet, so they decided to develop LifePro. LifePro provides information about different insurance types, such as personal insurance, group insurance, and company insurance. LifePro also provides further information on business forecasting and reports on the market.

Provenir Application

Provenir is a banking domain application that provides higher management reports, mainly for mortgages and loans. It includes information on customers and respective mortgages and loans. Higher management can draw a report any time to have a brief account of a number of customers and their liabilities to the company, organization, or bank.

Western Union Mobile Application

https://www.westernunion.com/us/en/mobile-app.html
A hybrid mobile application to help customer to transfer money to the inter-continent. The application was built to handle complex country financial rules while transferring money. The application supported tracking money transfers, paying bills, reviewing exchange rates, and finding agent locations. We have supported major payment gateways around the world.

Education

2011 - 2013

Master's Degree in Computer Science

Pune University - Pune, Maharashtra, India

2007 - 2011

Bachelor's Degree in Computer Science

Pune University - Pune, Maharashtra, India

Skills

Libraries/APIs

React Redux, React, FusionCharts, Node.js, Lodash, PrimeNG, Reactstrap, React Query

Tools

GitHub, Git, Webpack 3, Jira, Webpack, Slack, Grunt, Gulp, Mongoose, Figma, Asana, Webpack 4

Languages

JavaScript, HTML, CSS, HTML5, ES7, ECMAScript (ES6), SCSS, TypeScript, JavaScript 6, CSS3, GraphQL, Less

Frameworks

Redux, Angular, AngularJS, Express.js, Bootstrap, Tailwind CSS, Vanilla JS, React-Bootstrap, MUI CSS, Flutter, Bootstrap 3, Next.js, Material UI

Paradigms

Management, UI Design, Responsive Web Design (RWD), Security Software Development, Responsive, Microfrontends

Platforms

MacOS, Visual Studio Code (VS Code), Contentful

Storage

JSON, MongoDB

Industry Expertise

Web Design

Other

Information Technology, User Interface (UI), Front-end, Front-end Development, Teamwork, Fintech, Web Development, UI Development, Software as a Service (SaaS), Algorithms, Axios, Communication, eCommerce, Fintech Consultant, Finance, Responsive UI, Data Visualization, Dashboards, Web Dashboards, AI Tools, Site Speed Optimization, Gatsby, Online Banking, APIs, Mobile App Development, Hybrid Apps, Responsive Design, Web UI, Web UX

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