Kosta Karathanasopoulos

Software Engineer & Applied Mathematics @ Brown University

I build things across AI/ML, full-stack web, prediction markets, and computer vision. Currently an undergraduate researcher at Brown's SWRL Lab and seeking SWE and quantitative roles.

Selected Projects

PresidentialBrief

Full-stack SaaS that delivers personalized AI-generated weekly news briefs via email. User auth, scheduled cron jobs, and OpenAI-powered content generation.

Next.jsTypeScriptPostgreSQLOpenAIPrisma

Spike

Prediction market platform with real-time dashboards, leaderboards, clubs, and admin panels. Complex multi-page React frontend backed by a FastAPI service.

Next.jsReact 19FastAPIPostgreSQLTailwind

RoadsAndSearch

GitHub →

Interactive visualizer for 6 pathfinding algorithms on a procedurally generated 1000x1000 town. BFS, DFS, Dijkstra, A*, Greedy Best-First, and Bidirectional search.

JavaScriptHTML5 CanvasAlgorithms

PartSelect Chat Agent

GitHub →

AI chat agent for appliance parts with real scraped product data, compatibility checks, installation guides, and intent classification via Deepseek LLM.

ReactNode.jsDeepseekBeautifulSoup

Habit Forest

Visual habit tracker where habits grow as L-system trees when maintained and decay through 50 stages when neglected. Procedural generation on canvas.

Next.jsTypeScriptZustandCanvas APIFramer Motion

YouTube Focus Mode

Chrome extension that intelligently hides entertainment content on YouTube while preserving educational videos. Floating controls, keyboard shortcuts, and on-page stats.

JavaScriptChrome Manifest V3Content Scripts

Voice AI Assistant

GitHub →

Voice-to-text AI assistant running on Cloudflare Workers with Whisper STT and Llama 3.3. Durable Objects for persistent conversation memory.

TypeScriptCloudflare WorkersWhisperLlama 3.3

TikTok View Predictor

Novel power-law decay model for predicting TikTok video views. Accounts for frontloaded distribution, creator momentum, and viral signals. Real-time WebSocket logging.

FastAPIReactPlaywrightGemini Vision

Go AI — Parallel MCTS

Go game AI achieving 88.3% win rate using Root Parallel MCTS with 8 workers, Zobrist hashing, opening books, and territory-aware heuristics.

PythonPyTorchMultiprocessingMCTS

Recruit Analysis Tool

Rowing recruit scouting platform for Brown Athletics. Coaches can discover, filter, and track recruits with detailed profiles and batch web scraping.

ReactViteReact Router

Polymarket Tools

Python library for Polymarket prediction markets. Arbitrage detection, orderbook analysis, position tracking, and market discovery.

PythonhttpxPandas

CoinClicker

GitHub →

Smart contract gaming lottery on Flare Network. Won 1st place ($7,500) at the Easy A x Flare x XRPL Hackathon.

SolidityFlare NetworkJavaScript
1st Place — $7,500

Scratchoff

GitHub →

Interactive blockchain scratch-off game with smart contract management on Polkadot. Won 2nd place ($3,000) at the Harvard x Polkadot Hackathon.

JavaScriptSmart ContractsPolkadot
2nd Place — $3,000

Sketch

GitHub →

Quantitative trading system with event-driven executions and algorithmic trading strategies on Algorand.

PythonAlgorandSmart Contracts
Honorable Mention

Goldman ELS Calculator

GitHub →

Financial calculator for mutual fund investments using the CAPM model. Calculates future value based on historical returns, beta, and risk-free rates from the FRED API.

ReactNode.jsExpressCAPM

Markov Decision Simulator

GitHub →

Browser-based MDP solver and simulator. Draw states and actions, solve via Value Iteration, and simulate policy execution. Fully standalone, no server required.

JavaScriptHTML5 CanvasAlgorithms

Wikipedia Random Walk

GitHub →

Explores Wikipedia via a category-aware random walk, building a weighted multigraph rendered as a live D3 force layout with hop-based colouring and audio cues.

D3.jsMediaWiki APIWeb Audio API

Tetris

GitHub →

Feature-complete Tetris with procedural sound generation, ghost piece preview, hold functionality, and progressive difficulty at smooth 60 FPS.

PythonPygameNumPy

YOLOV8 Rowing Analysis

GitHub →

Real-time pose estimation overlay for rowing videos using YOLOv8. Frame-by-frame body angle analysis with interactive controls and confidence thresholds.

PythonYOLOv8OpenCVNumPy

Rowing Telemetry Tools

GitHub →

Animated stats overlay from rowing telemetry data and statsheet generator. Imports CSV data and renders video overlays via FFmpeg.

PythonMatplotlibFFmpegNumPy

Experience

Spike
Goldman Sachs ELS
Brown SWRL/LUNAR
Hats by the Hundred

Founding Engineer / Co-founder

Spike • New York City • Jan 2025 – Present
  • Architecting the core React frontend and user experience. Secured $150,000 in angel funding.
  • Accelerated product development by adopting AI-native workflows (Cursor, Copilot) to rapidly prototype and iterate on complex UI states
  • Optimizing technical architecture to support high-throughput interactions between users and autonomous backend systems

Goldman Sachs Emerging Leaders

Goldman Sachs • Jan 2026 – Apr 2026
  • Creating a mutual fund analysis tool with a React/TS frontend coupled with a FastAPI/Python backend
  • Leveraging OpenAI API to provide qualitative insights into users' investment strategy

Research Assistant, AI/ML Robustness

Brown University, SWRL/LUNAR • Providence, RI • Jan 2025 – Dec 2025
  • Designed red-teaming strategies to stress-test LLMs, identifying prompt patterns that trigger hallucinations in agentic decision loops
  • Co-authored a paper on linguistic bias (SVO/OVS triad) in modern text-to-image models

Software Engineer Intern

Hats by the Hundred (E-Commerce) • Brisbane, Australia • Nov 2023 – Sep 2024
  • Designed an autonomous sales agent (RAG-based) using internal support data that now generates $80K in annual revenue
  • Analyzed Shopify customer data to identify conversion patterns and optimize the UX for maximum engagement

Education

Brown University

B.S. Applied Mathematics–Computer Science

GPA 3.85 • May 2028

D1 Rowing (20+ hrs/wk) • Quantitative Trading at Brown • Full Stack at Brown • Brown Builders • Brown Chess Club

The Southport School

Queensland Certificate of Education

ATAR 99.55 • Graduated Nov 2023

School Prefect • House Captain • Rowing Vice Captain • Tennis Captain

Awards & Recognition

Hackathons

  • 1st Place — Easy A x Flare x XRPL Hackathon ($7,500)
  • 2nd Place — Harvard x Polkadot Hackathon ($3,000)
  • Honorable Mention — Algorand Hackathon

Athletics

  • Australian Rowing National Championships — Double Scull
  • Queensland State Champion — Single, Double, and Quad Scull
  • Queensland State Medallist — Men's Eight

Certifications

  • Yale Financial Markets (Coursera)
  • Stanford Machine Learning Specialization

Tech Stack

Python · JavaScript · TypeScript · C++ · Java · Bash · SQL · React · Next.js · FastAPI · Node.js · React Native · Git · RAG · Agentic Patterns · Cursor · GitHub Copilot · OpenAI API · NumPy · Pandas · Linux · Shopify+

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