I build systems that aresecure & scalable.
Software Engineer at Spense, building secured credit card infrastructure that empowers 200M+ Indians with their first credit card. Turning complex banking problems into clean, scalable digital products.
const developer = {
name: "Sahil Sudan",
role: "Software Engineer",
company: "Spense",
frontend: ["React", "Next.js",
"TypeScript", "Tailwind"],
backend: ["Node.js",
"Spring Boot", "Java"],
devops: ["Docker", "Git"],
domain: "Fintech & Banking"
};
About Me
The engineer behind the code.
Sahil Sudan
Software Engineer @ Spense
📍 Based in Bengaluru
I build products that are secure & intuitive.
I'm Sahil Sudan — a passionate Software Engineer currently working at Spense, where I build the complete secured credit card infrastructure that empowers 200M+ Indians with their first credit card.
At Spense, I work on bank-grade infrastructure — from digital onboarding & KYC flows to card issuance, payment processing, and credit bureau reporting. The platform handles 100K+ cards in circulation, 1.5M+ monthly transactions, and 105M+ APIs consumed monthly.
I specialize in developing modern web applications with a strong focus on both frontend and backend technologies. My core expertise lies in React.js, Next.js, and TypeScript on the frontend, and Node.js + Java Spring Boot on the backend.
Strong In
Also Worked With
Tech Stack
What I build with and what I've worked on.
Strong In
Also Worked With
Experience
My professional journey building fintech infrastructure at scale.
Software Engineer (Full-Time)
Spense
Promoted to full-time after a strong internship. Continuing to build and scale the secured credit card infrastructure — owning key modules across the platform. The Spense platform powers 100K+ cards in circulation, 1.5M+ monthly transactions, and 105M+ APIs consumed monthly.
Software Engineer Intern
Spense
Joined Spense as an intern and contributed to building the complete secured credit card platform that empowers 200M+ Indians with their first credit card. Worked across the full stack — from digital onboarding & KYC flows to card issuance, payment processing, and graduation to unsecured credit. Deployed directly inside bank environments.
Spense Platform Scale (company-wide)
Projects
Key products and systems I've built at Spense and beyond.
Secured Credit Card Platform
Core platform at Spense enabling banks to launch fully functional secured credit card programs in 90 days. Complete lifecycle from onboarding, KYC, deposit & lien, card issuance to graduation — deployed inside bank environments.
No-Code Admin Panel
Configuration layer enabling banks to set up card programs without coding. Maker-checker workflows, full UAM, compliance controls, white-label branding, and flexible program rules for fees, limits, and risk appetite.
Digital Onboarding & KYC
Seamless digital onboarding flow with phone/email verification, PAN & Aadhaar verification, CAF & address verification, and Video KYC with bank officials. Fully compliant with RBI and DPDP regulations.
Payment & Transaction Engine
High-volume transaction processing handling 1.5M+ monthly transactions across POS, E-commerce, and UPI. Bill payments via FD & EMIs, recurring deposits, and dynamic limit enhancement.
Card Lifecycle Management
End-to-end card management — virtual & physical card issuance, card controls, delivery tracking, activation workflows, closure with compliance sync, and automated refund processing.
Graduation & Credit Bureau Reporting
Automated credit bureau reporting and compliance workflows. Customers with strong repayment history graduate from secured to unsecured credit limits through repayment analysis and credit score evaluation.
System Design, Made Simple
Complex topics explained with real-world analogies. No jargon, just clarity.
Rate Limiting — The Bouncer at Your API's Door
Why does Instagram stop you from liking 500 posts in a minute? Rate Limiting. Let's understand how it protects systems from abuse — with a nightclub bouncer analogy.
Read article →Load Balancing — Explained Like You're Ordering Food
Ever wondered how Netflix handles millions of users at once without crashing? The secret is Load Balancing. Let's understand it with a simple restaurant analogy.
Read article →Horizontal vs Vertical Scaling — Adding More Trucks vs a Bigger Truck
When your app can't handle the load, do you get a bigger server or more servers? Let's understand scaling with a delivery truck analogy.
Read article →Let's Connect
Working on interesting fintech projects or want to talk about modern web development? I'd love to hear from you.
I'm always open to discussing new projects, creative ideas, or opportunities to be part of your vision.