Entrepreneur, agency owner, and senior full-stack engineer based in the UK. I design and ship production-grade AI tooling, SaaS products, and developer infrastructure.

I run hgray.agency, where I build live products across healthtech, fintech, restaurant ops, edtech, logistics, femtech, and developer tooling.

Production-grade RAG pipelines with evaluation baked in. A framework-agnostic CLI that scaffolds production RAG systems, runs continuous evaluation as a CI/CD gate, and scores any pipeline against the RAG Maturity Model (RMM-0 to RMM-5).

Six packages live on npm and PyPI. TypeScript CLI plus a Python pipeline, delegated through a subprocess bridge. MIT licensed.

• Docs: rag-forge-docs.vercel.app
• Website: rag-forge-site.vercel.app
• Install: npm i -g @rag-forge/cli

A pre-hyperopt screening framework for testing whether a candidate trading signal carries information over a baseline — before you spend cloud hyperopt budget finding out it doesn't. Four mechanical screens (coverage, lift, Jaccard, information-split) run in seconds on a laptop and produce a JSON verdict. Methodology applies to any signal hypothesis on any asset class; the repo ships a worked crypto case study where four well-known strategies failed pre-committed criteria — one of them killed by SIA in ~3 seconds, before any hyperopt ran. Apache 2.0.

• Blog write-up: Four crypto strategy failures, and the tool that caught one in 3 seconds
• Install: pip install -e git+https://github.com/hallengray/signal-independence-audit

A follow-up case study within SIA: a regime-switching strategy that combined two strategies which had already failed on their own, riding a trend-following signal in bull markets and buying dips in sideways ones. It became the first signal in the whole project to clear the SIA screen, then lost money out-of-sample anyway (best run about -9% over 16 months, profit factor 0.78, Sharpe roughly -0.23). The regime switching worked correctly. One of its two legs was simply unprofitable on unseen data, and the other could not carry it. A clean reminder that clearing the screen means "worth the expensive test," not "this works."

• Full kill record: case-study/11-mss-kill-adr-0027.md

Commercial and client products I've built end-to-end. Code is private. Some are live, others are in development for clients.

PearMedica (live) — B2B SaaS API for medical intelligence in Africa. Enterprise-ready symptom assessment and clinical triage powered by medical LLMs, a production RAG system, and deep African disease knowledge. NDPA-compliant.

Correx (live) — Find the cheapest way to send money abroad. Compares live quotes from leading providers across UK to Nigeria, UK to Ghana, UK to India, and more.

NosHQ (live) — Multi-tenant restaurant POS built with Next.js 16, Supabase, and shadcn/ui. Real-time order management, kitchen display system, floor planning, inventory, and full UK compliance (VAT, allergens, tip law).

Molly's Wellness Club (live) — A wellness platform for postpartum women across the UK. Personalized support, nutrition tracking, community engagement, and expert guidance.

AkwaabaTech (in development, client project) — Ghana's first comprehensive educational platform combining affordable vocational training (barbing, carpentry, fish farming) with digital skills courses.

VanGo (in development, client project) — Uber-style van hailing for bookings, moves, and deliveries. Instant booking, real-time tracking. Built on React 19, Next.js 15, TypeScript, and Tailwind CSS 4.

AuraTest (in development) — AI-driven test management platform with autonomous test orchestration. An intelligent Test Manager handles project setup, test planning, and reporting while testers focus on manual execution.

Beyond RAG-Forge and SIA, a handful of smaller tools and personal experiments:

• n8n-nodes-twelvedata — n8n community node for Twelve Data financial APIs
• supabase-auth-starter — Reusable Next.js + Supabase authentication template with OAuth
• BPT — Blood pressure tracking app with daily readings, diet, and exercise logging
• football-edge (personal) — Big-5 football value-betting tool with per-league trained models, live UK bookmaker odds, AI-explained picks, and a paper-trading tracker. Live demo (password-gated)

Frontend: Next.js 16, React 19, TypeScript, Tailwind CSS, shadcn/ui Backend: Supabase (PostgreSQL, Auth, Storage, Edge Functions, Realtime), Node.js, Python AI: Anthropic, OpenAI, RAGAS, DeepEval, OpenTelemetry, MCP Infra: Vercel, Turborepo, pnpm workspaces, uv, GitHub Actions

• Website: hgray.agency
• LinkedIn: linkedin.com/in/femi-adedayo-h44
• X / Twitter: @hallengray
• GitHub: @hallengray