Real-world architectural decisions and technical approaches from production systems I've built.
These case studies document my problem-solving process without exposing proprietary code. Each study covers the business problem, technical approach, trade-offs considered, and lessons learned.
| Study | Domain | Key Technologies |
|---|---|---|
| Building a Visa Risk Scoring Engine | Immigration Tech | OpenAI, LangChain, PostgreSQL |
| AI-Powered Medication Search | Healthcare | OpenAI Embeddings, MongoDB Vector Search |
| Study | Domain | Key Technologies |
|---|---|---|
| Scaling a Fintech Platform with Redis | Fintech | Redis, Node.js, Query Optimization |
| Multi-Tenant EdTech Architecture | EdTech | PostgreSQL, Row-Level Security, NestJS, WebSockets |
| Building a Cross-Platform Telemedicine Platform | Healthcare | Next.js, React Native, Twilio Video, MongoDB |
Each case study follows this format:
- Context — The business problem and constraints
- Approach — Technical decisions and why I made them
- Architecture — System design with diagrams
- Trade-offs — What I considered and why I chose this path
- Results — Measurable outcomes
- Lessons Learned — What I'd do differently
These case studies demonstrate experience with:
- Frontend: React, Next.js, React Native, TypeScript, TailwindCSS
- Backend: Node.js, NestJS, Express, Python
- Databases: PostgreSQL, MongoDB, Redis
- AI/ML: OpenAI GPT-4, LangChain, Embeddings, RAG Pipelines
- Real-time: WebSockets, Twilio Video
- Cloud: AWS (EC2, S3, Lambda), Docker, Vercel
- Patterns: Microservices, Multi-tenancy, Event-driven, CQRS
As a consultant and contractor, much of my production work is under NDA. These case studies allow me to demonstrate:
- Architectural thinking — How I approach complex problems
- Trade-off analysis — How I evaluate options and make decisions
- Production experience — Real challenges from real systems
- Communication skills — Explaining technical concepts clearly
David Sampson — Senior Full Stack Engineer
These case studies are shared for educational purposes. Please don't copy them verbatim — use them as inspiration for documenting your own work.