Varnika Yadav — SWE · CS + Math @ Penn State

Varnika Yadav

Software for messy, real-world problems.

I’m a CS + Math double major at Penn State who builds full-stack, AI-powered tools for farms, payroll, hospitals and city water lines, and tests them until the numbers hold up.

Want to build together?Let’s talk

what i do

I’m a full-stack developer.

I find a problem someone is losing money, time or sleep over and ship a working product around it, usually in 36 hours, with a team, on very little sleep. TypeScript, React and Next.js on the front; Python and FastAPI on the back; LLMs and ML models where they actually earn their place.

Off the hackathon floor I’m a strategy analyst at PSU Quants and an undergraduate researcher studying systemic risk, so I care a lot about whether the numbers are right.

See the work

TypeScript✦JavaScript✦React✦Next.js✦Tailwind CSS✦shadcn/ui✦TanStack Query✦HTML/CSS✦Python✦FastAPI✦Flask✦Node.js✦Bun✦WebSockets✦REST APIs✦Convex✦Redis✦SQL✦XGBoost✦scikit-learn✦pandas✦GeoPandas✦Backtesting✦C✦Java✦Linux/Unix✦Git✦Vitest✦Playwright✦Zod✦Snyk✦Vercel✦Render✦Kotlin/Android✦

how i build

01 ·
Find the real problem.
Before we wrote a line of RollPay, my teammate had a 29-page payroll runbook and a log of 125 real problems from three pay periods. We built for those, then walked a 25-person restaurant in Oakland through it to make sure it wasn’t one company’s headache.
02 ·
Prove it works.
Demos are easy. I’d rather show receipts. RollPay matched 35 of 46 real pay periods to the cent and caught 59 of 60 planted errors with zero false alarms. Blue Grid’s model put 73% of the pipes that actually broke into its highest-risk group.
03 ·
Keep a human in the loop.
Every message RollPay’s AI drafts gets approved by a person before it sends. Nod redacts emails, phone, card and bank numbers before anything is stored, and blocks any feature with a medium-or-higher Snyk finding.

selected work

Things I’ve shipped.

8 hackathon builds · 4 prizes · live demos below

№ 01
Terrametric
Live crop-stress scores, 14-day forecasts and dollar-priced prescriptions that tell growers which field to treat first.
- XGBoost scores stress per field from five satellite signals (NDVI, NDWI, SWIR heat stress, NASA SMAP soil moisture, rainfall deficit), and a second model prices it in dollars from USDA yields and crop prices ($888/acre corn, $628/acre soybeans).
- A FastAPI backend streams 120+ live field records over WebSockets to a 3D globe and real-time dashboard.
- An ROI engine weighs each fix’s cost against loss avoided and the cost of waiting.
- Event-driven SMS alerts go out for high-risk fields.
- Python
- FastAPI
- WebSockets
- XGBoost
- Next.js
- TypeScript
- GLSL
- SQLite
- Vercel
event
Bitcamp 2026 (UMD)
w/ Abhinav Dasari, Vidyut Sriram
Award: 3 prizes
★ Real World Prize (Ambrook track)
★ Best Champion of Open Source w/ Featherless
★ Best Intermediate Data Science Track Hack
Live Terrametric (opens in a new tab)
Code Terrametric (opens in a new tab)
Devpost Terrametric (opens in a new tab)
№ 02
FireDrill AR
An immersive fire drill for kids and students: scan a real room and it becomes a fire you can see, hear and feel.
- A headset scan of the room becomes the stage: fire spreads across the floor and furniture, smoke drops from the ceiling so students learn to stay low, and EXIT and BLOCKED signs mark the way out.
- DataFeel haptic dots on both wrists warm up on the side the fire is on, buzz in the smoke and cool down at the safe exit, with skin-safe limits (38 °C max, automatic cut-outs).
- A Claude voice coach answers questions from the live room state, and every run ends with a review: the path taken, escape time, time in smoke and how long you stayed low.
- three.js
- WebXR
- Vite
- FastAPI
- WebSockets
- Claude API
- AssemblyAI
- DataFeel
- Unity
event
MOLTEN Spatial Hackathon, LA Tech Week 2026
6 hours · team of 5 · Apple Vision Pro
w/ Devajsinh Solanki, Prakhar Goel, Emma Sun, Haotian Yin
Award: DataFeel winner
★ Best Use of DataFeel (DataFeel track)
★ Won a $1,500 DataFeel kit
Live FireDrill AR (opens in a new tab)
Code FireDrill AR (opens in a new tab)
№ 03
RollPay
An AI payroll assistant that catches bad hours before payday and hands the owner a payroll that’s right.
- Syncs Jobber, QuickBooks and Gusto, runs 23 rule-based checks on hours, rates and pay, and drafts a Gusto payroll for the owner to approve.
- When pay data doesn’t add up, it texts the right worker or manager a short question over iMessage. A human approves every AI-drafted message first.
- Validated on an anonymized real landscaping company: 35/46 pay periods matched to the cent, 59/60 planted errors caught with zero false alarms, and 700+ automated tests.
- TypeScript
- Next.js
- React
- Convex
- Claude API
- Bun
- Vitest
- Playwright
- Zod
- iMessage
event
Cal Hacks 13.0 (UC Berkeley)
36 hours · team of 3
w/ Devajsinh Solanki, Shanin Drucquer
Live RollPay (opens in a new tab)
Code RollPay (opens in a new tab)
Devpost RollPay (opens in a new tab)
№ 04
Nod
Five AI agents that turn founders’ customer interviews into ranked, quote-backed feature cards, then write and ship the code.
- A 5-agent system built in Python/Flask goes from raw interview transcripts to prioritized, quote-backed feature cards to shipped code.
- Shared long-term memory with Cognee, so customer insights, conflicts and security lessons persist across restarts.
- PII is redacted from every transcript before storage. Any feature with a medium-or-higher Snyk finding is blocked from shipping.
- Python
- Flask
- AI agents
- Cognee
- Snyk
- Flexprice
event
AI Startup Challenge, AWS Builder Loft 2026
6 hours · team of 3
w/ Anusha Agarwal, Vedant Shirvi
Award: Top 5
★ Invited to speak at the AWS AI Summit
Code Nod (opens in a new tab)
№ 05
Blue Grid
Finds the city water pipes most likely to break next and gives crews a 72-hour plan to fix them first.
- Trained on a real city’s open data (its full pipe inventory and complete break history), scoring every pipe on age, material, past breaks and flood exposure.
- Backtested: 73% of pipes that actually broke landed in the model’s highest-risk group.
- A Leaflet map over real pipe geometry, Claude-written action plans and explanations, and a Browserbase agent that pulls fresh break records from the city’s live data portal.
- Python
- Flask
- scikit-learn
- pandas
- GeoPandas
- Redis
- Leaflet.js
- Claude API
- Browserbase
- Render
- Vercel
event
UC Berkeley AI Hackathon 2026
Live Blue Grid (opens in a new tab)
Devpost Blue Grid (opens in a new tab)
№ 06
Echo by Relay
From one sentence a doctor says out loud, Echo makes sure the patient actually gets their medicine.
- Voice-first: it checks coverage and prior-auth requirements, then routes the patient to a free bridge supply, a patient assistance program or cash pay.
- Drafts prior-authorization letters that cite exact sentences from the drug’s FDA label, so every clinical claim is traceable.
- Explains the plan to patients in Spanish or English. Caregivers see nothing until they sign a consent and privacy agreement.
- TypeScript
- Next.js
- Supabase
- Tailwind CSS
- xAI Grok
- Vercel
event
HackGT 13 (Georgia Tech)
w/ Vedant Shirvi, Anant Patel
Live Echo by Relay (opens in a new tab)
Code Echo by Relay (opens in a new tab)
Devpost Echo by Relay (opens in a new tab)
№ 07
Would You Jump?
A private AI matchmaker for co-founders. You only find out who someone is once you’ve both said yes.
- Models run in the visitor’s browser: Laya through ONNX Runtime Web in a web worker, and Bonsai 1.7B through Transformers.js and WebGPU. Your pasted background never leaves your device.
- Introductions need two independent approvals before names or contact details are revealed.
- Built on Next.js, React, TypeScript and TanStack Query with Supabase Postgres. Optional cloud enhancement only ever sees fields you approved.
- TypeScript
- Next.js
- React
- TanStack Query
- Supabase
- ONNX Runtime Web
- Transformers.js
- WebGPU
event
National Renaissance Hackathon at super{set}
w/ Harsh Rathi, Abhinav Dasari, Anusha Agarwal
Live Would You Jump? (opens in a new tab)
Code Would You Jump? (opens in a new tab)
Devpost Would You Jump? (opens in a new tab)

More builds

WatchCare-AI
NexHacks @ Carnegie Mellon · 24 hours
Real-time fall detection on existing hospital camera feeds: pose estimation flags slumps and slides, and Firebase pushes alerts to an Android nurse app with claim/resolve and an audit trail.
Python · OpenCV · MediaPipe Pose · Firebase Firestore · Kotlin
- Code WatchCare-AI (opens in a new tab)
- Devpost WatchCare-AI (opens in a new tab)
FadeThat
Idea to live deploy in 3 hours
Paste any article and it ranks every claim by how wrong it is, in under 10 seconds.
Next.js · TypeScript · Tailwind · Claude API · Vercel
- Live FadeThat (opens in a new tab)
- Code FadeThat (opens in a new tab)
mysh
CMPSC 311
A Unix shell in C with pipes, I/O redirection, background jobs and env-var expansion.
I built the tokenizer/parser, process execution, signal handling and background jobs (fork, execvp, waitpid, dup2, sigaction), and checked memory with Valgrind.
C · Valgrind
- Code mysh (opens in a new tab)

hackathon log

[Oct 2026]MOLTEN · LA Tech Week: FireDrill AR, won DataFeel
[Apr 2026]Bitcamp 2026: Terrametric, won 3 prizes
AWS Builder Loft 2026: Nod, won Top 5
Cal Hacks 13.0: RollPay
UC Berkeley AI Hack 2026: Blue Grid
HackGT 13: Echo by Relay
super{set} Renaissance: Would You Jump?
[Jan 2026]NexHacks @ CMU: WatchCare-AI

Cal Hacks 13.0

Hey, I’m Varnika!

I’m a double major in Computer Science and Mathematics at Penn State, class of 2028. I like problems where the math and the people both matter: crop losses, payroll, patients waiting on prescriptions, aging city infrastructure.

I go to three or four hackathons a semester, and I help run them too: I’m on the education team for HackPSU, Penn State’s flagship hackathon, and on the exec team of Builders Collective, where I run idea-to-prototype workshops and take members to hackathons.

Penn State Math Club · Directed Reading Program Scholar

experience

Experience

Strategy Analyst, Microstructure Trading Algorithm
PSU Quants
Sept 2025–Present · State College, PA
Analyze high-frequency order book data to model liquidity imbalances, spread dynamics and trade impact. Backtest strategies on Sharpe ratio, drawdown and execution efficiency, and work with engineers to turn trading logic into code.
Undergraduate Researcher
Dr. Stefan M. Lewellen, Penn State
Jan 2026–Present
Quantitative models of shadow banking, systemic risk and financial intermediation.
Learning Assistant & Grader
Penn State Mathematics
Aug 2025–Present
Learning assistant for MATH 220 (Matrices, 50+ students) and MATH 230 (Calculus & Vector Analysis); grader for MATH 22 (80+ students) and MATH 230.
National EdTech & IT Intern
Lavner Education
May–Aug 2026 · Philadelphia, PA
Supported IT for 50+ STEM summer camp sites nationwide (robotics, Minecraft, Roblox and AI programs) and resolved 900+ support tickets, working directly with instructors to keep camps running.

Leadership

Education Team Organizer
HackPSU
Sept 2025–Present
Plan pre-hackathon workshops with campus clubs and run voting and judging at Penn State’s largest hackathon.
Executive Team: Event Planner & Secretary
Builders Collective
May 2026–Present
Helped run c0mpiled-15 ($10K+ in prizes) and get Penn State teams to hackathons in SF and LA.
Web Manager
Penn State ERO Billiards Club
Feb 2026–Present
Run the club site: schedules, results, tournament sign-up forms and weekly recaps.
Team Lead
Women Power Society
2020–2023
Led a program that taught 100 adults in slum communities to read and write in Hindi.

education

The Pennsylvania State University

B.S. Computer Science & B.S. Mathematics, expected May 2028

Coursework: Data Structures & Algorithms · Systems Programming · Probability · Linear Programming · Real Analysis

off the clock

Off the clock.

languages i speak

Hindi
native
English
full professional
Punjabi
full professional

when i’m not coding

Billiards
ERO Billiards Club
Cats
Horses
Memes

always learning

Machine Learning Specialization
DeepLearning.AI & Stanford · 2025
NAiSS Machine Learning Bootcamp
Nittany AI Student Society · 2026
Directed Reading Program
Number theory & proofs · 2026
Penn State Math Club

good fit?

Where I’ll be useful.

I’m looking for Summer 2027 software engineering internships: full-stack, backend, AI/ML, or quant-dev teams.

We’ll get along if your team ships fast, sweats whether the numbers are actually right, and wants an intern who has already taken products from an empty repo to a live demo in 36 hours, with tests.

Hiring?Let’s talk

toolbox

01
Full-stack web.
- TypeScript
- JavaScript
- React
- Next.js
- Tailwind CSS
- shadcn/ui
- TanStack Query
- HTML/CSS
02
Backend & real-time.
- Python
- FastAPI
- Flask
- Node.js
- Bun
- WebSockets
- REST APIs
- Convex
- Supabase/Postgres
- Firebase Firestore
- Redis
- SQL
03
AI & ML.
- LLM APIs (Claude, Grok, DeepSeek)
- Multi-agent systems
- XGBoost
- scikit-learn
- Pose estimation (MediaPipe/OpenCV)
- In-browser inference (ONNX Runtime Web, Transformers.js, WebGPU)
04
Data & quant.
- pandas
- GeoPandas
- Satellite & geospatial data
- Backtesting
- Order-book analysis
- Probability & linear programming
05
Systems & shipping.
- C
- Java
- Linux/Unix
- Git
- Vitest
- Playwright
- Zod
- Snyk
- Vercel
- Render
- Kotlin/Android

let’s build

Let’s build something.

Internship, hackathon team, or a problem that needs building? My inbox is open.

varnika2271@gmail.com

Varnika YadavVarnikaYadav

I’m a full-stack developer.

// how i build

Find the real problem.

Prove it works.

Keep a human in the loop.

Things I’ve shipped.

Terrametric

FireDrill AR

RollPay

Nod

Blue Grid

Echo by Relay

Would You Jump?

More builds

WatchCare-AI

FadeThat

mysh

// hackathon log

Hey, I’m Varnika!

// experience

Experience

Strategy Analyst, Microstructure Trading Algorithm

Undergraduate Researcher

Learning Assistant & Grader

National EdTech & IT Intern

Leadership

Education Team Organizer

Executive Team: Event Planner & Secretary

Web Manager

Team Lead

Off the clock.

// languages i speak

// when i’m not coding

// always learning

Where I’ll be useful.

// toolbox

Full-stack web.

Backend & real-time.

AI & ML.

Data & quant.

Systems & shipping.

Let’s build something.

I’m a full-stack developer.

// how i build

Find the real problem.

Prove it works.

Keep a human in the loop.

Things I’ve shipped.

Terrametric

FireDrill AR

RollPay

Nod

Blue Grid

Echo by Relay

Would You Jump?

More builds

WatchCare-AI

FadeThat

mysh

// hackathon log

Hey, I’m Varnika!

// experience

Experience

Strategy Analyst, Microstructure Trading Algorithm

Undergraduate Researcher

Learning Assistant & Grader

National EdTech & IT Intern

Leadership

Education Team Organizer

Executive Team: Event Planner & Secretary

Web Manager

Team Lead

Off the clock.

// languages i speak

// when i’m not coding

// always learning

Where I’ll be useful.

// toolbox

Full-stack web.

Varnika Yadav

how i build

hackathon log

experience

languages i speak

when i’m not coding

always learning

toolbox

how i build

hackathon log

experience

languages i speak

when i’m not coding

always learning

toolbox