Software Engineer · full-stack, RAG/LLM systems & mobile
Founder & sole engineer of Sapenor (legal-tech) · founder of Bishamon Games (mobile studio)
- 💻 Software engineer; founder of Sapenor (legal-tech) and Bishamon Games (mobile studio)
- 🏗️ I build the infrastructure — I built and run my own RAG stack from scratch, instead of calling a hosted one
- 📏 I measure before I ship: an eval harness and deterministic checks decide what goes to production, including what doesn't
- 📱 Shipped several apps to the App Store and Play Store, and built the Bishamon Games studio site
- 🎓 B.Eng. Mathematical Engineering, Yıldız Technical University
RAG · vector search · bge-m3 · HNSW · tool-calling agents · LLM evaluation · citation verification · model routing · pgvector · Chrome Extensions (MV3) · Row-Level Security · RealityKit · ARKit · RoomPlan · photogrammetry · LiDAR depth fusion
An end-to-end platform for Turkish lawyers: retrieval-augmented research, drafting, document analysis, litigation simulation, and integration with the national court system (UYAP). Designed, built and operated solo — a product in production, not a prototype.
- Self-hosted RAG, no framework. A Python/FastAPI retrieval service on
bge-m3, two-stage vector search — binary-quantized HNSW candidates re-ranked by cosine onhalfvec(1024)— over PostgreSQL +pgvector. - Measured retrieval. Reciprocal rank 0.38 → 0.92; empty-result queries 4/8 → 0/8, driven by deterministic legal-abbreviation expansion and query distillation.
- Reliability first. A three-layer eval harness, and deterministic citation verification without an LLM — decision numbers in an answer matched against the chunks actually retrieved, so hallucinations are caught at zero API cost.
- Cost engineering. A hybrid router sends simple questions to a model ~13× cheaper (fail-open, env kill-switch), plus prompt caching and delta-only case memory → ~67% lower inference cost per question.
- Shipped. Next.js 16 · React 19 · TypeScript · Supabase (Auth + RLS) · streaming chat · a Manifest V3 Chrome extension for UYAP import · three LLM providers behind a registry whitelist.
Source is on GitHub — each one built to run, not to demo.
| Project | Description | Stack |
|---|---|---|
| 3D-Showroom | An offline sales tablet for cabinet doors — the customer swaps colours, stretches the door in real centimetres, and sees it in their own room at true size. Preset thumbnails are rendered on-device; the profile outlines come from a depth-based Metal shader, not from the model. | Swift · SwiftUI · RealityKit · ARKit · SwiftData · Metal |
| ObjectScanner | 3D-scans real objects and rooms on-device — photogrammetry, turntable, TrueDepth and RoomPlan behind one output contract. Reads back the solver's own camera poses to diagnose a bad capture instead of guessing at it. | Swift 6 · RealityKit · ARKit · RoomPlan |
| circlio-split-bills | Shared-expense app — groups, live balances, settlement suggestions. On the App Store » | Flutter · Firebase · Riverpod |
| KeyClickSoundApp | A click on every keystroke, system-wide. A listen-only keyboard hook that never records what you type. | Tauri · Rust · React |
| pdf-book-translator | Translates English book PDFs into Turkish, keeping chapters and images. Two-tier OCR, free offline first. | Python · PySide6 · PyMuPDF |
| CarpetWebsite2 | A carpet-showroom storefront — filterable catalogue, no framework, no build step. Live » | HTML · CSS · JS |
Products live on the App Store and Google Play. More at the Bishamon Games portfolio »
| App | Description | Stack |
|---|---|---|
| Circlio | Split shared expenses with groups, multi-currency and real-time sync. | Flutter · Firebase |
| PetlyFans | A social network for pets — real-time chat, feed, and swipe matching, on a full Firebase backend. | Unity · Firebase |
| Skeleton Survivors | A mobile roguelike, published end-to-end with in-app purchases and ads, tuned across a wide device range. | Unity · C# |
| Drive Quest | An online racing game — gameplay mechanics, QA and localization. | Unity · C# |
I also led prototyping and optimization for Car King, a multiplayer mobile game published on iOS and Android, and built the Bishamon Games studio site itself.
Most of my day-to-day work lives in Sapenor's private repository.