Ege Yesilyurt

Daily logic-puzzle game, live at zebra9.xyz

It runs on a commit-based solver that scores the guesses you lock in as you go, so the game rewards real reasoning over a lucky final grid.

• Wordle-style daily puzzle with 200+ unique players, all solving the same date-seeded grid.
• Commit-based solving engine with overwrite scoring and server-rendered share cards.
• Optional account sync for cross-device streaks; automated deploys on Vercel.

Pokémon TCG collector platform, 6-person team

Reviewed 8 teammate pull requests with written scores and follow-up fixes, catching a WebSocket handler that crashed on dead sockets and an N+1 query on the marketplace feed.

• Largest contributor on a 6-person team (66 of 140 commits) across the digital binder, card-recognition scanner, and listing-scoped marketplace.
• Built binder persistence end to end across a Docker Compose monorepo: Next.js web, FastAPI backend, and a FastAPI scanner service on AWS Rekognition.
• 80+ backend tests covering auth, listings, and the scanner pipeline.

The constraint-solver engine behind z9bra

Used CP-SAT as a uniqueness oracle instead of hand-checking puzzles, so every shipped daily is provably single-solution. No unsolvable or ambiguous grids reach players.

• Python engine that uses OR-Tools CP-SAT as a uniqueness oracle, so every puzzle is provably single-solution.
• Custom propagation tracer measures human deduction depth to score and tune difficulty.
• Built with strict TDD: property-based tests, dual-implementation cross-checks, mypy-strict clean.

Your Spotify history as a 3D voxel city, live

Offloaded Spotify history ingest to Celery background jobs so the OAuth flow stayed instant while heavy pulls ran out of the request path.

• Spotify OAuth with on-demand history ingest via Django + Celery jobs.
• Genre rollup turns your artists into districts of a 3D voxel city in React Three Fiber, scored by a test-first ranking engine.
• Shareable public profiles and a postcard generator; deployed on Vercel + Railway.

Workout training planner web app

Led the 6-person team and pushed for a repository-pattern data layer so the backend stayed testable under a tight deadline.

• Project lead for a 6-person agile team, running sprint planning and delegation in Jira.
• User/trainer auth, fitness profiles, program scheduling, and workout recommendations.
• Repository-pattern data layer covered by Django unit tests, fully containerized.