AI Full-Stack Engineer — I build LLM-powered products end to end: real-time transcription pipelines, RAG, agents, and the React/Next/Node surfaces around them.

6+ years shipping production web apps. Four of them in AdTech — Prebid.js header bidding, Google Ad Manager, and the ad delivery engine itself, on sites serving billions of monthly impressions (details below). These days my build time goes to AI: streaming voice, retrieval, tool-calling agents, and the unglamorous parts — evals, cost control, and making it hold up under real traffic.

• 🔭 Currently building: a human-in-the-loop control plane for AI agents (approve / deny / edit risky tool calls before they run)
• 🧠 Working with: OpenAI · Anthropic · LangChain / LangGraph · Vercel AI SDK · Deepgram · pgvector
• 🌍 Islamabad, Pakistan — open to remote roles and select freelance work
• 📫 msameedkhan25@gmail.com · Portfolio · LinkedIn

A working note, not a portfolio — most of these live in private repos while they're in progress. Happy to demo any of them.

🎙️ AI Interview Copilot — for the people running interviews. A Next.js dashboard generates role-specific questions from a JD and a résumé; a Chrome extension teleprompter keeps them in front of you during the call. A meeting bot joins the Zoom/Meet/Teams call, transcription streams back over websockets, and a post-call pass turns it into candidate reports and side-by-side comparisons. Hono · Bun · Next.js · Deepgram · Drizzle · Supabase

🧪 DevPrep — AI Interview Agent — the other side of the same problem: practice. Mock interviews across 150+ technical topics at junior/mid/senior difficulty, AI scoring with a per-question breakdown, and a learning plan generated from whatever you got wrong. Tracks score trends per topic over time. Next.js · OpenAI · Clerk · Postgres

🎓 GuideMeYar — a university admissions guide for Pakistani students: fees, deadlines, scholarships, and program comparison across Islamabad, Lahore, and Karachi. The interesting part is the data pipeline — a scraper never writes to a live table. It writes a proposal, which gets validated, diffed against current data, and human-reviewed before it goes live, because a wrong admission deadline is worse than a missing one. Next.js 15 · TypeScript · Supabase · Firecrawl · provenance tracking

🎨 Brand Creative Studio — on-brand social creatives from a brand profile plus a one-line idea. Layered prompt composition (brand → template → intent → mode), multi-model image routing so you pick the best of four renders instead of re-rolling one, and a deterministic overlay pass for what models still get wrong — logo placement and exact text. Next.js · OpenRouter · prompt engineering

🏙️ Real Estate Intelligence — a research agent for the Islamabad property market. Ingests listings and area data, keeps it clean and comparable, and answers the questions that actually decide a purchase: how two sectors compare, what changed recently, where the legal or possession risk sits. TypeScript · Prisma · Postgres · LLM research pipeline

📖 Project Story MCP Server — an MCP server that reads commits, PRs, and diffs and hands back the raw material for a case study or a résumé bullet. One rule it doesn't break: the server ships structured data, never prose — the writing stays with whoever's asking. TypeScript · MCP · GitHub API

AI / LLM — OpenAI · Anthropic · LangChain · LangGraph · Vercel AI SDK · RAG · pgvector / Qdrant · Deepgram · MCP Frontend — React · Next.js (App Router) · TypeScript · Tailwind · React Native Backend — Node.js · Express · Python · GraphQL · REST · WebSockets / SSE Data & infra — PostgreSQL · Supabase · MongoDB · AWS (EC2 / S3 / CloudFront) · Docker · Cloudflare Workers · GitHub Actions AdTech — Prebid.js · Prebid Server (S2S) · Google Ad Manager · GPT · OpenRTB · header bidding · schain · UPR · TCF / GDPR · Kibana Quality — Vitest · Jest · React Testing Library · Playwright

Four years building the JavaScript that monetizes publisher pages — header bidding, ad delivery, and the measurement around it — across sites serving billions of monthly ad impressions. If you're hiring for AdTech, this is the part that matters.

Ad delivery engine — architected from scratch (TypeScript) Modular design with separate config, feature, auction, and GPT managers. Rollup feature-flag tree-shaking plus Terser got the bundle 4× smaller than the engine it replaced — enough to win back LATAM publishers who had left over page-speed — and delivered a 150–200% page RPM lift on test domains.

Prebid.js header bidding — built from scratch inside it Promise-based auction flow · size-mapping filter that drops incompatible bidders by device width and ad-unit size · geo-based bidder allow/deny lists · Prebid Currency Module with a custom PKR fallback · schain · price-granularity tuning · analytics signals (winner, bidder, bid, size).

Client-side and server-to-server: shipped S2S auctions on Prebid Server in production, moving bidders off the page to cut client-side latency and payload — and tuning around the signal-loss trade-off that comes with it. Led the client-facing side of a major publisher's Prebid rollout, from discovery through estimation.

Ad formats, owned end to end Siderail (+7–15% page RPM confirmed in production), Anchor, Chaser, Interstitial, Drifting, Auto Ads, Offerwall with floor-price override, Google Lazy Load — architecture through cohort rollout for each.

Privacy, consent, and invalid traffic Traffic Cop in both sync (bundled) and async (dynamic injection) modes, so publishers get per-site performance profiles. TCF API / CMP integration: consent-gated auctions, no-data-without-consent enforcement, COPPA support, EU visitor detection. Diagnosed and fixed a broken CMP on a top-earning publisher, restoring lost revenue.

Measurement — you don't ship ad code on vibes Built a multi-cohort, multi-domain A/B testing platform streaming live revenue, page-speed, and feature metrics into Kibana. Every script change validated against cohorts before full rollout.

Also Per-unit ad-preference activation across 7 features, driven by DB params instead of deployments · a viewability investigation that surfaced a Smart Refresh bug affecting every script version · competitive teardowns of rival monetization scripts, with findings presented at an AdTech industry event in Brazil · BPMN process documentation and mentoring on the engine's architecture.

Prebid.js · Prebid Server (S2S) · Google Ad Manager · GPT · OpenRTB · header bidding · schain · UPR · TCF / GDPR · Traffic Cop · Kibana · A/B testing

The AdTech code itself is proprietary and stays private. Happy to walk through the architecture and the trade-offs on a call.

Ad code runs on someone else's page, in every browser, under a page-speed budget, with money attached to every millisecond. Six years of that is where the habits come from — cohort-validate before rollout, measure what you ship, assume the network is hostile.

That's what I bring to AI work. The demo is the easy part.

_{Public repos are going up as I clean each project for release. Want a walkthrough of something that isn't up yet? Email me — I'd rather show you than describe it.}