# Thaalank Ranjan > Lead Software Engineer @ Capital One Location: New York City Metropolitan Area, United States Profile: https://flows.cv/thaalank Technical Lead and Backend Engineer with 5+ years of experience, specializing in real-time customer-critical data platforms, with end-to-end ownership from architecture through production and strong cross-team technical leadership. ## Work Experience ### Lead Software Engineer @ Capital One Jan 2026 – Present | New York, New York, United States ### Senior Software Engineer @ Capital One Jan 2024 – Jan 2026 | New York, NY Enterprise Tech | Customer Core | Customer Demographics & Customer Preferences Technical Lead / Backend Engineer on Customer Demographics and Preferences, core platforms managing demographic and preference data at scale across Capital One. Key Contributions: • Customer Attribute Service (CAtS) – Designed and architected CAtS end-to-end, a self-service platform for managing customer attributes within Customer Demographics. Reduced attribute onboarding time from 6–9 months to minutes, enabling Customer Core to scale from 6 attributes toward 50+. Led platform architecture, database schema, and contribution model; led 2 teams to production onboarding of multiple attributes, establishing the foundation for future growth. • Platform Reliability – Improved Customer Preferences platform to Capital One’s highest reliability tier by automating regional failovers and optimizing RDS configurations. • Technical Leadership – Serve as Technical Lead for a team of 6 engineers, owning architecture, delivery execution, and technical quality. Conduct technical interviews and mentor engineers within and outside my organization. Serve on the Customer Core technical review council, reviewing ERDs and influencing architectural decisions. • Production Support – Serve as a Level 3 on-call engineer for both platforms, responding to high-severity incidents and supporting critical customer data workflows. • Recognition – FoCUS Tech Innovation Award (for CAtS); Enterprise Tech High-Flyer Award (Influence). Tech Stack: • Languages & Frameworks: Java, Spring Boot, Python • Data Stores: Cassandra, PostgreSQL, DynamoDB • Cloud & Infrastructure: AWS (Fargate, ECS/EC2, Lambda, Batch) • Distributed Data Processing: Spark, EMR, Glue • AI Tools: GitHub Copilot, Windsurf, Claude Code ### Software Engineer @ Capital One Jan 2023 – Jan 2024 | New York, NY Enterprise Tech | Customer Core | Money Movement Accounts Platform (MMAP) Backend Engineer on the Money Movement Accounts Platform, a core system managing external funding accounts for enterprise-wide payment processing and account funding. Key Contributions: • Cloud Migration & Infrastructure Modernization – Led the first serverless migration in Customer Core, transitioning AVS (Account Verification Service), a 1000+ TPS Platinum service, from ECS/EC2 to AWS Fargate. Rebuilt the service infrastructure end-to-end, including a dedicated AWS account, IAM roles, networking, security groups, and CI/CD pipelines, executing a zero-downtime production cutover and establishing a migration pattern for future services. • Cloud Cost Optimization (ARM64 / Graviton) – Launched and led the Customer Core Serverless Cost Optimization initiative, starting with AVS. Reduced AWS Fargate costs by ~40% with no performance impact by migrating to ARM64, enabling Graviton, and applying ARM-specific optimizations. Authored a CodeGenie PR to standardize ARM migration across Fargate services, enabling org-wide cost savings. • MMAP Notification Modernization – Designed and implemented a centralized email notification system for MMAP, providing a single, reusable mechanism for customer-facing account event communications and improving reliability and consistency across workflows. • Production Support – Served as an on-call engineer, responding to high-severity incidents and supporting customers managing external funding accounts. Tech Stack: • Languages & Frameworks: Java, Spring Boot • Data Stores: Cassandra • Cloud & Infrastructure: AWS (Fargate, ECS/EC2, Lambda) ### Associate Software Engineer @ Capital One Jan 2021 – Jan 2023 | New York, New York, United States Card Tech | Commercial Card Platform (CCP) Full-stack engineer on Capital One’s Commercial Card Platform (CCP), enabling enterprise customers to manage and pay multi-million-dollar invoices while earning rebates. Key Contributions: • Real-Time Payfile Details – Built a real-time payfile details experience by integrating backend APIs with frontend components, improving visibility into invoice and payment data. • Partial Payfile Submission & Download – Led frontend development for partial payfile submission and download workflows, collaborating closely with design partners to deliver a seamless user experience. • Virtual Card Funding Modernization – Contributed to the development and integration of a new service to modernize payment funding flows, transitioning from external tooling to Capital One’s internal payment infrastructure. • Production Support – Served as an on-call engineer, responding to incidents and supporting critical payment workflows. Tech Stack: • Languages & Frameworks: Java, Spring Boot, Spring WebFlux, TypeScript, Angular, RxJS • Data Stores: PostgreSQL • Cloud & Infrastructure: AWS (ECS/EC2) ### Founding Engineer @ Leva Jan 2020 – Jan 2021 | Richmond, VA Built and launched Leva as the founding engineer, a platform connecting students with high-growth startups, leading frontend architecture and delivering a responsive, production-ready web application. Key Contributions: • Frontend Development – Built the web application’s frontend using React, TypeScript, and React-Bootstrap, ensuring a responsive and user-friendly experience. • CI/CD Implementation – Set up continuous integration and deployment (CI/CD) using npm, Prettier (for automatic formatting), and AWS Amplify, streamlining the development workflow. • Business & Marketing – Led marketing and business development efforts to onboard students and startups, driving engagement and platform adoption. Tech Stack: • Languages & Frameworks: TypeScript, React, React-Bootstrap • Cloud & Infrastructure: AWS Amplify ### Software Engineer Intern @ Capital One Jan 2020 – Jan 2020 | Wilmington, Delaware, United States Bank Tech | Small Business Bank Worked on modernizing Capital One’s Small Business Banking web application by improving API architecture, performance, and maintainability through service segregation and orchestration. Key Contributions: • Monolithic API Segregation – Began decomposing a monolithic API with 50+ services into RESTful Python microservices to enhance separation of concerns (SoC), performance, and maintainability. • Orchestration Layers – Developed and deployed orchestration layers for Capital One’s Small Business Banking web application using Python and AWS Lambda, improving modularity and cloud efficiency. Tech Stack: • Languages & Frameworks: Python, Flask • Cloud & Infrastructure: AWS Lambda ### Software Engineer Intern @ Hindsait, Inc. Jan 2018 – Jan 2018 | Amherst, MA Developed components of Hindsait’s Natural Language Processing (NLP) software to extract and rationalize data from unstructured clinical notes, improving quality of care and reducing errors, fraud, and unnecessary services. Key Contributions: • Free-Text Parser – Developed a parser using spaCy to process unstructured clinical notes, parsing both complete and incomplete sentences into subjects and objects, resolving ambiguous pronouns, and identifying time-related references within sentences. Tech Stack: • Languages & Frameworks: Python, spaCy ### Research Assistant @ The Cooper Union for the Advancement of Science and Art Jan 2016 – Jan 2017 | New York, New York, United States Worked with Professor Anita Raja’s research group on NSF funded EAGER: Collaborative Research: Advanced Machine Learning for Prediction of Preterm Birth. Tech Stack: • Languages & Frameworks: Python, NumPy ### Software Engineer Intern @ Petasense Jan 2015 – Jan 2015 | San Francisco Bay Area Developed components of the web app. Tech Stack: • Languages & Frameworks: JavaScript, React ## Education ### Bachelor of Arts - BA (Cum Laude) in Computer Science Cornell University ### Associate of Science - AS in Physics Bergen Community College ### High School Diploma in Business Bergen County Technical High School - Teterboro ## Contact & Social - LinkedIn: https://linkedin.com/in/thaalank --- Source: https://flows.cv/thaalank JSON Resume: https://flows.cv/thaalank/resume.json Last updated: 2026-03-30