Naveen Raja, Developer in Chennai, Tamil Nadu, India
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Naveen Raja

Verified Expert  in Engineering

Bio

Naveen is a full-stack developer and a certified solutions architect specializing in designing and building robust back-end systems and APIs. He is proficient in JavaScript, Python, Java, Groovy, Go, and SQL. He has vast experience in the payments industry and has developed several payment solutions. Besides his development expertise, Naveen is a great communicator who enjoys programming challenges and always looks forward to learning new technologies.

Portfolio

Freelance Clients
Amazon Web Services (AWS), Docker, FastAPI, Gin-Gonic, HTML, JavaScript...
Picom Technologies
Python, Google Cloud, APIs, API Development, Google Cloud Platform (GCP)...
Zid
Django, PostgreSQL, Python, Mobile Wallet, B2B Wallets, MySQL...

Experience

  • Python - 8 years
  • Java - 7 years
  • JavaScript - 7 years
  • Node.js - 7 years
  • React - 6 years
  • Kubernetes - 5 years
  • Grails - 4 years
  • Groovy - 4 years

Availability

Part-time

Preferred Environment

Python, JavaScript, Java, Groovy, Grails, Node.js, React, FastAPI, Docker, Kubernetes

The most amazing...

...project I've developed is a one-stop payment solution for merchants called Express Checkout—the solution handles millions of transactions daily.

Work Experience

Senior Full-stack Developer

2022 - PRESENT
Freelance Clients
  • Designed and developed web applications through a variety of technologies for multiple clients.
  • Involved in architecting infrastructure of several applications.
  • Assisted with the development of APIs, UI, and application deployments.
Technologies: Amazon Web Services (AWS), Docker, FastAPI, Gin-Gonic, HTML, JavaScript, Kubernetes, Node.js, NGINX, Python, React, Redux, Solidity, SQL, Elasticsearch, Next.js, NestJS, TypeScript, Material UI, NoSQL, Google Cloud Platform (GCP), MongoDB, MySQL, Django, gRPC, Automation, Stripe, Cron, Amazon Elastic Container Registry (ECR), Solution Architecture, Celery, Payment Processing, Mobile Wallet, B2B Wallets, Technical Leadership, Amazon EKS, Amazon Simple Queue Service (SQS), Amazon ElastiCache, Amazon Simple Email Service (SES), Helm, Pytest, Locust, Distributed Systems, Django REST Framework, Asynchronous Programming, Containerization, Database Design, Database Optimization, Leadership, Performance Optimization, RESTful Services, Scalability, Sentry, Containers, GitHub, Redis Cache, Object-relational Mapping (ORM), AWS SDK, Python Asyncio, Asyncio, Task Scheduling, Orchestration, Async/Await, Software as a Service (SaaS), Amazon Aurora, Credit Cards, AWS Secrets Manager, Caching, CI/CD Pipelines, Code Review, GitHub Actions, System Architecture, Integration, Testing

Lead Back-end Developer

2024 - 2025
Picom Technologies
  • Served as the lead back-end developer for an AI-powered phone assistant.
  • Architected and developed the back end for an AI assistant that dials and completes the mission on behalf of the user at the scheduled time with the user's phone number.
  • Implemented new features, improved existing features, deployed code, and conducted code reviews, bug fixes, system maintenance, and customer support.
Technologies: Python, Google Cloud, APIs, API Development, Google Cloud Platform (GCP), Firebase, Webhooks, Redis, Amazon EKS, Amazon Web Services (AWS), Django, Heroku, Celery, Cloud Firestore, PostgreSQL, Amazon RDS, Twilio, Caching, CI/CD Pipelines, Code Review, GitHub Actions, System Architecture, Integration, Startups, Twilio API, Testing

Technical Lead (via Toptal)

2023 - 2024
Zid
  • Architected and developed a closed-loop wallet that's used by the players involved in the marketplace (merchants and their customers).
  • Designed and developed an intuitive admin dashboard catering to essential back-office functions.
  • Implemented new features, improved existing features, deployed code, and conducted code reviews, bug fixes, system maintenance, and customer support.
Technologies: Django, PostgreSQL, Python, Mobile Wallet, B2B Wallets, MySQL, Solution Architecture, Technical Leadership, Amazon EKS, Amazon Web Services (AWS), Kubernetes, gRPC, Docker, Containerization, Helm, Redis, AWS ELB, Amazon EC2, Pytest, Locust, JavaScript, React, Datadog, Sentry, Containers, GitHub, Redis Cache, Object-relational Mapping (ORM), AWS SDK, SQL, Protobuf, PCI DSS, Task Scheduling, Orchestration, Async/Await, Software as a Service (SaaS), Amazon Aurora, Credit Cards, AWS Secrets Manager, Caching, CI/CD Pipelines, Code Review, GitHub Actions, System Architecture, Integration, Startups, Testing, Multithreading

Senior Software Development Engineer

2020 - 2022
Razorpay
  • Involved in planning and implementing a rewrite of the legacy payment systems.
  • Developed an instant payment settlement system allowing merchants to settle their customers' payments to their bank accounts on the same day.
  • Implemented new features, improved existing features, deployed code, and conducted code reviews, bug fixes, and system maintenance.
Technologies: JavaScript, Node.js, Amazon Web Services (AWS), PostgreSQL, Kubernetes, Docker, Payment APIs, Card Payments, Digital Payments, Payment Processing, Online Payments, Payment Gateways, Solution Architecture, Amazon Simple Queue Service (SQS), Amazon ElastiCache, Python, Django, Pytest, Asynchronous Programming, React, Sentry, Containers, GitHub, Redis Cache, Object-relational Mapping (ORM), AWS SDK, SQL, PCI DSS, Task Scheduling, Orchestration, Async/Await, Software as a Service (SaaS), Credit Cards, AWS Secrets Manager, Caching, CI/CD Pipelines, Code Review, GitHub Actions, System Architecture, Integration, Startups, CyberSource, Testing, Multithreading

Senior Software Development Engineer

2016 - 2020
Juspay Technologies Pvt
  • Served as the lead developer and spearheaded the development and architecture of Express Checkout, a payment solution that handles millions of transactions daily through multiple payment instruments.
  • Architected and developed a single-click payment solution for digital wallets through deep linking.
  • Developed a standalone card locker that securely stores customers' card details, helping in easier payment flows.
  • Integrated 20+ payment gateways/aggregators into Express Checkout, thus elevating the product offerings.
  • Involved in the development of a merchant dashboard that helped merchants manage their payment gateways, routing rules, customer transactions, refunds, payouts, and analytics.
  • Implemented new features, improved existing features, deployed code, and conducted code reviews, bug fixes, system maintenance, and customer support.
Technologies: Groovy, Java, Grails, JavaScript, SQL, MySQL, Python, React, Apache Tomcat, HTML, Spring, Hibernate, Amazon Web Services (AWS), Quartz, Node.js, Kubernetes, Docker, Redux, Automation, Cron, Solution Architecture, Payment APIs, Payment Processing, Card Payments, Payment Gateways, Digital Payments, Online Payments, Mobile Wallet, B2B Wallets, Technical Leadership, Amazon Simple Queue Service (SQS), Amazon ElastiCache, Amazon Simple Email Service (SES), Helm, Pytest, Locust, Distributed Systems, Asynchronous Programming, Containerization, Database Design, Database Optimization, Leadership, Performance Optimization, RESTful Services, Scalability, Sentry, Containers, GitHub, Redis Cache, Object-relational Mapping (ORM), AWS SDK, PCI DSS, Task Scheduling, Orchestration, Async/Await, Software as a Service (SaaS), Amazon Aurora, Credit Cards, AWS Secrets Manager, Caching, CI/CD Pipelines, Code Review, System Architecture, Integration, Startups, CyberSource, Testing, Multithreading

Experience

ZidWallet

https://zid.sa
A merchant digital wallet for eCommerce platform and a marketplace and this innovative wallet includes a virtual IBAN feature, empowering customers to seamlessly oversee their purchases, receive payments for cash on delivery (COD) orders, and efficiently withdraw settlements.

In my role as the technical lead, I orchestrated the architecture and development of the merchant wallet, complemented by an intuitive admin dashboard catering to essential back-office functions. The solution was crafted as a robust gRPC application using Django (Python) and a PostgreSQL database, harnessing the power of cutting-edge technologies such as AWS, Kubernetes, Redis, Celery, Locust, Datadog, and Sentry.

Express Checkout

https://juspay.io/in/expresscheckout
A single API interface for all the payment gateways where merchants can choose from 100+ payment aggregators/payment gateways (PA/PGs) to process their online payments. Express Checkout, built with an intelligent routing system, helps merchants efficiently route transactions based on success rates, gateway health, and business logic. It reduces operational costs, improves success rates, and ensures 99.99% uptime.

As the project's lead developer, I wrote Express Checkout in Grails (Groovy) with a MySQL database. It leveraged several technologies, such as AWS, Redis, Nginx, Quartz, StatsD, Kibana, and Grafana. It was later rewritten in Node.js.

ZidWallet | Back-office Portal

https://zid.sa
The application was created using Django (Python) and a PostgreSQL database, leveraging technologies such as AWS, Kubernetes, Redis, Celery, Locust, Datadog, and Sentry, and it serves as a back-office application designed to efficiently manage the operations of merchant digital wallets, providing a comprehensive suite of tools to streamline tasks for operations and finance teams alike. It handles everything from reviewing merchant applications and verifying KYC to onboarding merchants, monitoring transactions, and managing refunds and withdrawals. With features like wallet analytics and treasury management, the app ensures seamless financial control.

Dropcall

https://apps.apple.com/us/app/dropcall-ai-phone-calls/id6738497713
An AI-powered phone assistant app revolutionizing communication with features like a smart AI agent for seamless conversations, customizable missions for goal-oriented calls, and an intelligent dialer ensuring calls appear from the user's phone number for trust and familiarity.

As the lead developer, I spearheaded the design, development, and deployment of this innovative application. Built using Django, PostgreSQL, Firebase, AWS, Kubernetes, Celery, and Redis, the app leverages cutting-edge AI technologies, including GPT and Gemini, to deliver a natural and engaging communication experience.

Card Locker

https://juspay.in/products
A secure and isolated card vault that allows merchants to save their customers' card information and retrieve it for further transactions. I was involved in developing new features and maintaining the application.

It was written in Grails (Groovy) with a MySQL database and AWS for cloud infrastructure.

Express Checkout Demo

https://bitbucket.org/juspay/ec-demo
A demo project, designed and developed by me, that showcases all the client's product offerings. The project shows all the checkout modes. Users can complete end-to-end transactions depending on the payment gateways configured in their account.

Prattle

https://github.com/naveenmraja/prattle.in
Prattle, which I designed and developed, is an anonymous chat application and a great way to meet new people. Prattle will pick someone random for a user and create a private chat session. The app will connect users with similar interests.

Prattle is built with MERN stack and uses several technologies like Redis, Docker, Kubernetes and NGINX.

CalTrack

https://github.com/naveenmraja/caltrack.tech
CalTrack, designed and developed by me, is a calorie-tracking app that lets you keep track of your daily food consumption. You can create a food entry for any date and edit and delete it anytime. CalTrack's dashboard provides useful insights into what the user consumes.

CalTrack was developed using MERN stack and uses technologies like Docker, Kubernetes and NGINX.

MySecrets

https://github.com/naveenmraja/mysecrets.tech
MySecrets, designed and developed by me, is a simple diary application that lets you record your memories. Users can create an entry for any date and edit and delete it anytime. MySecrets provides a dashboard to view and navigate all the entries.

MySecrets was developed in Node.js with React/Redux, AWS DynamoDB, NGINX, Docker and Kubernetes.

Assets Dashboard

A simple dashboard application, designed and developed by me, to display assets owned by the user with a pie chart. Users can filter assets based on the asset type using the filter menu or by clicking on the pie chart segment.

This was developed using FastAPI (Python), React, and Redux.

Education

2012 - 2016

Bachelor's Degree in Information Technology

SSN College of Engineering - Chennai, India

Certifications

JULY 2020 - JULY 2023

AWS Certified Solutions Architect – Professional

AWS

Skills

Libraries/APIs

Node.js, React, Socket.IO, Quartz, REST APIs, Amazon EC2 API, Sockets, Python API, React Router, React Redux, Pydantic, SQLAlchemy, API Development, Stripe, Protobuf, Python Asyncio, Asyncio, Twilio API, CyberSource

Tools

Amazon CloudFront CDN, NGINX, Apache Tomcat, Git, Amazon Simple Notification Service (SNS), Docker Compose, Amazon Elastic Container Service (ECS), AWS IAM, Bitbucket, AWS ELB, AWS CLI, Google Kubernetes Engine (GKE), Google Analytics, PyCharm, Cron, Celery, Amazon EKS, Amazon Simple Queue Service (SQS), Amazon ElastiCache, Amazon Simple Email Service (SES), Helm, Pytest, Sentry, GitHub, AWS SDK, AWS CodeDeploy, Amazon Elastic Container Registry (ECR), Firebase Authentication

Languages

Python, JavaScript, Java, Groovy, SQL, HTML, CSS3, HTML5, Python 3, CSS, ECMAScript (ES6), TypeScript, Solidity

Frameworks

Grails, Redux, Spring, Hibernate, Material UI, Express.js, Spring Boot, OAuth 2, Bootstrap, Django, gRPC, Locust, Flask, Gin-Gonic, NestJS, Next.js, Django REST Framework

Paradigms

REST, Socket Programming, Microservices, Test-driven Development (TDD), B2B, Unit Testing, API Architecture, Agile, Object-oriented Programming (OOP), Microservices Architecture, Back-end Architecture, Automation, Asynchronous Programming, Database Design, Object-relational Mapping (ORM), Testing, DevOps

Platforms

Docker, Kubernetes, Linux, Google Cloud Platform (GCP), Amazon EC2, Amazon Web Services (AWS), Firebase, Twilio, Heroku

Storage

MySQL, Amazon DynamoDB, Redis, Amazon S3 (AWS S3), MongoDB, Google Cloud, NoSQL, Databases, RDBMS, PostgreSQL, Relational Databases, JSON, Redis Cache, Amazon Aurora, Elasticsearch, Datadog, Cloud Firestore

Other

FastAPI, Software Development, Amazon RDS, Web Development, Software Development Toolkits (SDK), APIs, Full-stack Development, Back-end Development, Amazon Route 53, Full-stack, Back-end, Payment APIs, Architecture, API Integration, SaaS, Fintech, Front-end, SDKs, AWS Auto Scaling, Software Architecture, CI/CD Pipelines, Cloud, AWS Certified Solution Architect, AWS Cloud Architecture, Stock Trading, Stock Market, Web Applications, Front-end Development, User Experience (UX), MVC Frameworks, HTTP, User Interface (UI), Engineering, Webhooks, MERN Stack, Integration Testing, OAuth, Dashboards, Admin Panels, Third-party APIs, Back-end Performance, Payment Gateways, Solution Architecture, Payment Processing, Mobile Wallet, B2B Wallets, Technical Leadership, Distributed Systems, Containerization, Database Optimization, Leadership, Performance Optimization, RESTful Services, Scalability, Card Payments, Containers, PCI DSS, Task Scheduling, Orchestration, Async/Await, Software as a Service (SaaS), Credit Cards, AWS Secrets Manager, Caching, Code Review, GitHub Actions, System Architecture, Integration, Startups, Multithreading, ECS, WebSockets, Computer Science, Digital Payments, Online Payments

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