Tech Lead · Cloud, System Design & AI
Sunil Kumar Reddy Buddala
Building systems that move money, care and good causes.
Tech lead with a founder's mindset and experience across payments, healthcare and non-profit platforms, building scalable cloud systems and AI-assisted engineering workflows.
Tech Lead @ Visa · Auckland, New Zealand
15+
years building software across payments, healthcare & non-profits
$100K+
monthly donations processed by platforms he built as a founding member
1st
place, Startup Weekend Auckland 2015
What I do
Five threads that run through every role.
Technical leadership
Feature Lead for Visa's multi-partner Accounts Modernization, coordinating cross-team dependencies across product, UX and engineering through synchronised multi-release rollouts. Mentors junior engineers and buddies new joiners, and is the team's go-to for resolving critical production issues.
Cloud & system design
Scalable .NET microservices and React microsites on AWS with Docker containers. CQRS, event-driven, Clean Architecture, from Visa's account platforms to bootstrapped donation systems.
Security champion
Finds and fixes security issues in code reviews and system design, troubleshoots vulnerabilities and proposes secure solutions, and keeps payment flows PCI-DSS compliant. Leads security assessments with architecture diagrams security architects praised for making reviews "much easier" - zero blockers through the secure SDLC.
AI-assisted engineering
Custom Claude Code skills and MCP integrations that automate change requests and release docs, adopted by other teams. Early GenAI advocate and internal ambassador. An interest that started long before the tooling: a fuzzy-logic NLP project in 2007 and postgraduate research on EEG classification with neural networks at AUT.
Entrepreneurial builder
Thinks like a founder inside and outside work: won Startup Weekend Auckland 2015, founding member of DonateKart and DevaSeva, bootstrapped ventures still processing $100K+ monthly, and treats every feature like a product, owning it from idea to operations.
Experience
The short version - the full history lives in the CV.
Senior Developer → Tech Lead
Visa · Auckland · payments at global scale
2019–NOW
Solutions Developer
Fisher & Paykel Healthcare · Auckland · monolith → services, OAuth2 / OIDC
2016–19
Software Engineer → Senior
Software Innovation · Public 360° ECM, Nordic stakeholders
2011–15
Assistant System Engineer
Tata Consultancy Services · Web apps for the IMF
2009–11
Side venture · 2016–2023
DonateKart & DevaSeva
Founding member of DonateKart and DevaSeva, bootstrapped donation platforms still live today with $100K+ in monthly transactions and PCI-compliant payments across Stripe, Razorpay, PayU and Paytm. Recruited and led two 4-person teams; owned architecture through AngularJS → React → Next.js and .NET 4.8 → .NET 6 migrations.
Achievements
Competitions, rankings and records collected along the way.
- 2025
Top 3, Secure Code Warrior "Battle the Balrog"
Secure-coding tournament at the 2-day OWASP New Zealand Day conference, University of Auckland. Representing Visa as the team's Security Champion.
LinkedIn post - 2015
Winner, Startup Weekend Auckland
1st place out of the competing teams, pitching and building a product over one weekend while studying at AUT.
- 2012
Guinness World Record, Windows App Fest
Part of Microsoft's Windows App Fest '12 in India, recognised as a Guinness World Record for the largest app-building marathon.
- 2005
State rank 219, AP EAMCET
Ranked 219 in Andhra Pradesh's engineering entrance exam among approximately 1,14,946 candidates, the top 0.2% statewide.
What colleagues say
From written peer and manager feedback at Visa.
Thanks, Sunil, for all the work you do as the Security Champion for Volans - the confidence you bring the team in security matters is much appreciated. You're our release superhero, with the consistency and professionalism you've shown across sprint delivery, reviews and follow-ups.
...his meteoric rise to be a true technical expert and thought leader has been inspiring to see.
Sunil has taken on the feature leading role for the new Accounts functionality and he has done great work preparing stories for the team and co-ordinating between different parties to ensure questions are answered. He delegates work to the team when required but is always across the items himself.
This is how teams should collaborate - enabling each other to succeed.