A trading platform built like an institution. Run by one person.

Most trading tools fall into one of two categories: consumer apps so simplified they're useless for serious traders, or enterprise platforms so complex they require an ops team to configure. There was no middle ground for the technically sophisticated individual trader who wanted full control without the overhead.

Nexural was built to fill that gap — a production-grade fintech platform with real-time execution, portfolio tracking, a Discord-native AI companion, and a subscription billing layer that doesn't break on webhook retries.

The challenge: building a system at this scale — 185 relational database tables, 69 API endpoints, real-time market data ingestion, and a Stripe integration that needs to survive every edge case — without a dedicated backend team, a QA department, or a six-month runway for architecture review.

PostgreSQL on Supabase with Row-Level Security for multi-tenant isolation and real-time subscriptions via Supabase channels for live portfolio updates. Backend: FastAPI (Python) — async-first, typed with Pydantic, organized into domain-bounded modules. Frontend: Next.js with server components for data-heavy pages and client components for interactive trading UI.

Real-time via WebSocket connections for live price feeds; Supabase realtime for portfolio state synchronization. Stripe with idempotent webhook handlers, subscription lifecycle management, and metered feature gating. Discord bot backed by OpenAI GPT-4 with tool-calling for portfolio queries, market commentary, and alert management.

The philosophy: don't build features until the foundation is right. The first two weeks were data modeling — no UI, no API, just entity-relationship design, understanding where the RLS policies needed to live, and mapping every Stripe event to a database state.

185 PostgreSQL tables with full RLS policy coverage. 69 REST/WebSocket API endpoints (FastAPI). Real-time portfolio dashboard (Next.js + Supabase realtime). Trade execution interface with order management. Discord AI bot: portfolio queries, alerts, natural-language market commentary.

Stripe billing: subscription tiers, metered usage, trial periods, webhook idempotency. 61 test suites: unit, integration, E2E, contract, and security tests. CI/CD pipeline with GitHub Actions — no PR merges without passing gates.

The Stripe webhook layer is built on idempotency keys and event deduplication — a pattern now templated into micro-saas-starter on GitHub. The Discord bot uses function-calling to query the live portfolio API, meaning it responds to "how is my AAPL position" with real data, not hallucinated commentary.

Platform operational: live, stable, serving active users. Zero billing incidents since launch — the idempotent webhook architecture holds. AI bot handling 200+ natural-language portfolio queries per week.

61 test suites provide regression coverage for all critical paths. Architecture patterns extracted into 3 open-source templates used in subsequent projects.

A single engineer, with the right architecture discipline and AI-assisted development workflow, can build and maintain a system at this complexity level. The 185-table schema isn't a vanity number — it's a data architecture that needed to be right before anything was built on top of it.