Publication
Declarative vs. Imperative Programming: A Practical Guide for Choosing the Right Paradigm
https://www.toptal.com/developers/software/declarative-vs-imperative-programming
Thomas is available for hire
Hire ThomasThomas Varghese
Verified Expert in Engineering
Software Developer
Kochi, Kerala, India
Toptal member since October 15, 2020
Bio
Thomas is proficient in designing and developing web applications across the stack. In prior roles, he worked as a SaaS developer, high-frequency algorithmic trader, and CRM/ERP/MIS consultant, where test-driven development with 100% coverage was never optional. Insights gained from exposure to diverse domains, formal training in aerospace and computational engineering, and deep functional knowledge complement Thomas' technology chops.
Portfolio
Numbervine Technologies
Redux Thunk, Node.js, Postman, SimpleTest, Java, Amazon Web Services (AWS)...
Mercero Inc
Node.js, MongoDB, Authentication, TypeScript, Koa, Git, Unix, Security Groups...
Northstar Research Partners (UK) Ltd
JavaScript, HTML, CSS, React, Strapi, Amazon EC2, Amazon Route 53, A/B Testing...
Experience
- Express.js - 4 years
- Socket.IO - 4 years
- MongoDB - 4 years
- React - 4 years
- WebRTC - 3 years
- Docker - 2 years
- Cypress - 1 year
Preferred Environment
JavaScript, Amazon Web Services (AWS), Node.js, Java, MongoDB, Docker, React, Koa
The most amazing...
...application I've built is a peer-to-peer communication-enabled, declarative programming paradigm-based platform for streamlining process workflows.
Work Experience
Principal
2007 - PRESENT
Numbervine Technologies
- Developed an enterprise software product using the MERN stack, Socket.IO, and WebRTC, for adaptive business processes, leveraging cellular data connectivity as a base case scenario and driver of integration functions absent in legacy architectures.
- Designed and developed a task scheduling and monitoring engine that feeds off workflow definitions in XML and exposes a suite of task administration functions via a REST API built using the Yii2 PHP framework.
- Built an eCommerce platform using the LAMP stack and the Yii2 framework to market a range of website promotion services.
- Integrated PayPal and BitPay payment gateways with a web application built on the Yii2 PHP framework using custom modules.
- Engaged with clients directly on long-term work-for-hire contracts for analytics and SEO. Developed a novel P-hash image search-powered strategy to boost organic search traffic to a client site marketing illustration services.
- Shared responsibility for support, development, and maintenance of IT infrastructure: micro sites for lead generation and tooling for AdSense configuration and feedback generation for management of campaigns with daily budgets averaging $50,000+.
- Integrated reporting and data visualization tools with scripts and web applications - PHPExcel for auto generation of custom Excel formatted reports, JFreeChart for visualization of time series, and more recently, WebDataRocks.
- Contributed to the development of a client's automated order fulfillment pipelines for their suite of services for link building and allied SEO techniques.
- Built tools for decoding real-time price feed data from a VSAT terminal, and scraping of relevant inputs from various other sources, followed by FIX protocol compliant UDP multicast of this data over the LAN using Java.
- Built a trade execution engine to support a proprietary algorithmic trading business by leveraging Java's Robot class to emulate manual actions on native software provided by the broker-dealer as a workaround for not having API access at the time.
Technologies: Redux Thunk, Node.js, Postman, SimpleTest, Java, Amazon Web Services (AWS), Material UI, Webpack, Git, WebRTC, Jest, Cypress, Yii 2, PHP, HAProxy, Docker, MySQL, Express.js, MongoDB, Socket.IO, Redux-Saga, Redux, React, JavaScript, Firebase, Google Analytics, Data Scraping, Web Scraping, Financial Systems, Spring Boot, Front-end, GitHub, Automation, Audio Streaming, Babel, Backtesting, Backtesting Trading Strategies, Quantitative Modeling, Data Visualization, PostgreSQL, Error Handling, Multi-tenant SaaS, Back-end Development, Back-end Architecture, React Native, Claude API
Senior Back-end Developer | Technology Architect
2021 - 2025
Mercero Inc
- Handled feature development, testing, and maintenance across the entire technology stack distributed across microservices deployed on AWS, Digital Ocean, and Vercel.
- Architected and developed an email services back end integrated with Microsoft Outlook API (Graph API), Google API, and Twillio Sendgrid, optimized for bulk email delivery, with tracking and reporting built in.
- Administered a deal desk Salesforce app through the entire product lifecycle, while also playing a lead role in the development of custom components.
- Developed a publish-subscribe architecture implemented using Socket.IO server integrated with an HTTP server running on Amazon Elastic Beanstalk. Solved Socket.IO configuration issues related to dynamic instance scaling.
Technologies: Node.js, MongoDB, Authentication, TypeScript, Koa, Git, Unix, Security Groups, Web Security, Stripe API, Stripe, Amazon Web Services (AWS), JavaScript, React, Vercel, AWS Elastic Beanstalk, AWS Lambda, Amazon Simple Email Service (SES), Amazon Simple Queue Service (SQS), Auth0, OAuth 2, Amazon S3 (AWS S3), ChatGPT, SendGrid API, Google APIs, Microsoft Graph API, GraphQL, React Apollo, MongoDB Atlas, Tailwind CSS, Material UI, Socket.IO, Postman, Claude, Prompt Engineering, AI Prompts, ChatGPT Prompts, Apollo, Startups, Microservices, API Integration, Event-driven Architecture, Full-stack, Architecture, Software Design, Redis, RESTFul APIs, Google Maps API, Twilio, Data Scraping, Web Scraping, Python, Artificial Intelligence (AI), Progressive Web Applications (PWAs), Figma to React, REST APIs, API Gateways, Event-driven Design (EDD), Front-end, Full-stack Development, Webhooks, AI Tools, User Interface (UI), User Experience (UX), CI/CD Pipelines, FastAPI, GitHub, OpenAI API, Payment Gateways, JSON Web Tokens (JWT), ETL, Shopify, Large Language Models (LLMs), Shopify API, AI-generated Code, Supabase, Vibe Coding, Google Cloud Platform (GCP), Error Handling, Multi-tenant SaaS, Sentry, HubSpot API, Back-end Development, Back-end Architecture, AI Integration, Amazon DynamoDB, OpenAI, Claude Code, Cursor AI, Twilio API, SMS, AI Agents
eCommerce User Testing Web Platform Architect and Developer
2020 - 2021
Northstar Research Partners (UK) Ltd
- Architected a configurable technology solution for conducting large-scale conjoint analysis (A/B tests) on hundreds of volunteers simultaneously, over any number of options as per configuration.
- Developed this solution using Strapi for the management of study configuration and administration of the back end and the database. The front end was built using Next.js.
- Supported the client through launch and initial usage, and delivered detailed user documentation and video instructions for ongoing maintenance.
Technologies: JavaScript, HTML, CSS, React, Strapi, Amazon EC2, Amazon Route 53, A/B Testing, Docker, Docker Compose, Next.js, Containerization, Full-stack, Architecture, Software Design, Headless CMS, RESTFul APIs, Content Management Systems (CMS), Progressive Web Applications (PWAs), REST APIs, Front-end, Design, Full-stack Development, Webhooks, User Interface (UI), User Experience (UX), Kubernetes, GitHub, Error Handling, Multi-tenant SaaS, Back-end Development, Back-end Architecture
Founder and Technology Architect
2018 - 2020
LyfGrid Healthcare Private, Ltd.
- Designed and built an MVP for an open, omnichannel healthcare platform optimized for radical interoperability, with a marketplace and pathway for care model innovation.
- Led a team through a pilot go-to-market campaign and retooled key product components to support the entire gamut of customization requirements for electronic health records by specialty.
- Mapped ISO standard processes to roles and task definitions for clients in the mental health services sector.
Technologies: Rust, Redux Form, Redux, React, JavaScript, JSON, XML, MariaDB, MongoDB, HAProxy, Docker Compose, Docker, Full-stack, Architecture, Software Design, RESTFul APIs, Progressive Web Applications (PWAs), Multi-tenant SaaS
Trader and Financial Engineer
2005 - 2007
Jump Trading, LLC.
- Devised trading algorithms primarily using genetic algorithms and genetic programming techniques applied to market microstructure time series data.
- Oversaw integrity testing and performance optimization of numerous algorithmic trading strategies.
- Developed tools for real-time monitoring and administration of anywhere between 10 and 30 instances of trading strategies executing simultaneously on remote servers.
Technologies: Tradestation, High-frequency Trading (HFT), Subversion (SVN), TIBCO, Genetic Algorithms, Eclipse IDE, C++, Java, Trading, Full-stack, Software Design, Financial Systems, Backtesting, Backtesting Trading Strategies, Quantitative Modeling, Data Visualization, Fintech
Program Manager
2003 - 2005
Moran Research and Consulting, Inc.
- Developed decision support software enabling determination of material inputs for LASIK and cataract surgeries.
- Developed and deployed a networked practice management system that streamlined the outpatient pathway through an eye hospital, and later reconciled accounting reports with logs of tests administered.
- Configured and deployed an optimal, data science-enabled claim recovery prioritization model for a client in the medical insurance sector.
Technologies: Oracle Data Miner, Linux, MySQL, Java, Full-stack, Software Design, SQL
Business Analyst
2002 - 2003
HCL Enterprise Solutions
- Completed multiple engagements as a member of the technical team. Tasked with research, planning, and execution of steps for transition from legacy BI/ERP/MIS/CRM systems to the Oracle Applications Suite.
- Completed the end-to-end migration of legacy electronic data interchange (EDI) systems to ANSI X12.
- Reviewed compliance with industry standards for EDI and made recommendations for changes as applicable.
Technologies: Data Migration, SQL Loader, LoadRunner, PL/SQL, EDIFACT, Oracle Apps, ANSI X12, Oracle, SQL, Electronic Data Interchange (EDI), Enterprise Resource Planning (ERP), Data Mapping, ERP Implementation, SKUs, Third-party Logistics, ETL
Research Assistant
2000 - 2002
High Performance Computing Collaboratory (HPC²)
- Developed a novel paradigm for grid generation by the combination of intersecting grids over simple geometric shapes as a replacement for an otherwise tedious, albeit highly skilled, manual process.
- Published "An Octree-based overset mesh hole cutting method" in Proceedings of the 8th International Conference on Numerical Mesh Generation in Computational Field Simulations, pp. 783-792.
- Ran tests on large, real-world data sets and worked with collaborators to verify results.
Technologies: OpenGL, CVS, XML, Computational Fluid Dynamics (CFD), Computational Geometry, C
Experience
Programmable Workflow Administration Platform
End-to-end development of a Kanban-inspired, generic, declarative programming paradigm-based technology architecture for the definition and administration of workflows within organizational hierarchies. The product is deployed on the cloud using Docker containers as a SaaS, with a client managed cloud option for customers seeking total control over their data.
A/B Test Framework
Developed a framework for the ongoing deployment and analysis of A/B tests to evaluate and drive the content strategy team's decisions. This was built using JavaScript to register tracking information onto the server and PHP scripts to collate and create reports for analysis.
Automated Trading System
Developed a FIX protocol-compliant implementation of a high throughput trade execution engine for trading financial instruments in the National Stock Exchange of India. This program accepts trade strategies as serialized objects, aligned with edge computing architecture guidelines, ensuring the strategy component's privacy is not compromised.
Education
2000 - 2002
Master's Degree in Computational Engineering
Mississippi State University - Starkville, Mississippi, USA
1996 - 2000
Bachelor of Technology Degree in Aerospace Engineering
Indian Institute of Technology Bombay - Mumbai, India
Skills
Libraries/APIs
React, Node.js, React Redux, Redux Form, REST APIs, HubSpot API, Twilio API, Socket.IO, WebRTC, Redux-Saga, Stripe API, Stripe, OpenAI API, Shopify API, Claude API, Google APIs, Google AdSense, jQuery, OpenGL, JFreeChart, React Redux Form, SendGrid API, Google Maps API
Tools
GitHub, Sentry, Claude Code, AWS SDK, Git, NPM, Postman, MATLAB, Apache, Docker Compose, Atom, Eclipse IDE, Vim Text Editor, Subversion (SVN), CVS, Babel, Webpack, Front-end Build Tools, Bower Front-end Dependency Manager, Composer, LoadRunner, JSX, Redux Thunk, Amazon Simple Email Service (SES), Amazon Simple Queue Service (SQS), Auth0, ChatGPT, React Apollo, MongoDB Atlas, Claude, AI Prompts, Google Analytics
Languages
Java, JavaScript, PHP 7, PHP, HTML5, CSS, HTML, TypeScript, Python, JavaScript 6, CSS3, GraphQL, SQL, C, C++, XML, Rust, SCSS, Less
Frameworks
Next.js, Express.js, Redux, Yii 2, Cypress, Jest, Yarn, Material UI, Spring Boot, JSON Web Tokens (JWT), React Native, Materialize, SimpleTest, Laravel 5, Koa, OAuth 2, Tailwind CSS
Paradigms
REST, Back-end Architecture, RESTful Development, Microservices, ETL, Test-driven Development (TDD), Declarative Programming, Event-driven Architecture, Event-driven Design (EDD), Automation, Responsive Layout, Testing, E2E Testing, DevOps
Platforms
Vercel, Google Cloud Platform (GCP), Docker, Amazon EC2, Amazon Web Services (AWS), Firebase, Twilio, Kubernetes, Shopify, Oracle, Linux, Tradestation, Unix, AWS Elastic Beanstalk, AWS Lambda
Storage
MongoDB, Redis, MySQL, MariaDB, JSON, Amazon S3 (AWS S3), NoSQL, PostgreSQL, Amazon DynamoDB, PL/SQL, SQL Loader, Elasticsearch
Industry Expertise
Trading Systems, High-frequency Trading (HFT)
Other
Genetic Algorithms, Data Visualization, Back-end, APIs, Full-stack, API Integration, Architecture, Software Design, Headless CMS, RESTFul APIs, Data Scraping, Web Scraping, Electronic Data Interchange (EDI), Progressive Web Applications (PWAs), API Gateways, Full-stack Development, Webhooks, User Interface (UI), Data Mapping, ERP Implementation, SKUs, Backtesting, Backtesting Trading Strategies, Quantitative Modeling, Large Language Models (LLMs), AI-generated Code, Supabase, Vibe Coding, Fintech, Error Handling, Multi-tenant SaaS, AI Integration, SMS, AI Agents, Amazon Route 53, SaaS, Software as a Service (SaaS), Single-page Applications (SPAs), Software Architecture, WebSockets, Server-side Rendering (SSR), Payment Gateways, Front-end, Strapi, Trading, Apollo, Startups, Containerization, Content Management Systems (CMS), Artificial Intelligence (AI), Enterprise Resource Planning (ERP), Financial Systems, Figma to React, Design, AI Tools, User Experience (UX), CI/CD Pipelines, FastAPI, Audio Streaming, Third-party Logistics, OpenAI, Cursor AI, Computational Fluid Dynamics (CFD), Operating Systems, Networks, Computational Geometry, Data Structures, Artificial Neural Networks (ANN), IP Networks, ANSI X12, Oracle Apps, EDIFACT, Oracle Data Miner, HAProxy, Directed Acrylic Graphs (DAG), FIX Protocol, SEO Tools, Search Engine Marketing (SEM), Vi, TIBCO, Back-end Admin Systems, Back-end Development, Responsive Design, Responsive UI, Quality Assurance (QA), A/B Testing, Forex Trading, Forex Trading Room, Arbitrage, Data Migration, MERN Stack, Sagas, Axios, Authentication, Security Groups, Web Security, Microsoft Graph API, Prompt Engineering, ChatGPT Prompts
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