# Stu Mason for Oxford Dynamics

> Stu Mason's application for Senior Applied AI Engineer (Private Sector Contractor) at Oxford Dynamics, September 2026. Engineer, 15 years, ships agents with humans in the loop, MCP servers and eval suites in production. Everything here is checkable.

## Read
- [Full profile (markdown)](https://oxford-dynamics.stumason.dev/stu-mason.md): three-line pitch, why now, what I would build first, receipts, experience, stack.
- [CV (PDF)](https://oxford-dynamics.stumason.dev/stu-mason-cv.pdf): two pages, the one uploaded to Ashby.
- [Profile JSON](https://oxford-dynamics.stumason.dev/profile.json): structured facts with sources.

## Talk
- [MCP server](https://oxford-dynamics.stumason.dev/mcp): Streamable HTTP, no auth. Tools: get_profile, get_cv, get_receipts, ask_stu.
- [A2A agent card](https://oxford-dynamics.stumason.dev/.well-known/agent.json): endpoint https://oxford-dynamics.stumason.dev/a2a, message/send with a text part.
- Human: stu@stuartmason.co.uk, +44 7713 333312.

## Optional
- [GitHub](https://github.com/StuMason)
- [stumason.dev](https://stumason.dev)


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# Stu Mason, applying for Senior Applied AI Engineer (Private Sector Contractor) at Oxford Dynamics

Folkestone, Kent, UK (hybrid, Harwell two days a week) · stu@stuartmason.co.uk · +44 7713 333312 · https://stumason.dev · https://github.com/StuMason · https://linkedin.com/in/stumason · UK right to work · Age 42

## In three lines

- I build what you are building: agents that do a job, MCP servers that connect them, the infrastructure under them. My open-source MCP server for Coolify has 603 GitHub stars and 18,800 npm installs in the last 30 days (checked 26 Sep 2026).
- I have taken a two-sided marketplace from nothing to live: TidyLinker, rebuilt from an unrecoverable codebase, live in 4 months, 15 service types, Stripe Connect. Still running it with the founders.
- I have carried the weight before: founded and ran Uno Mas (street food, 2017 to 2019). Seven years leading platform engineering at Pfizer.

## Why this, why now

Two years shipping agents that do a job in production: Bellwether (4.7M items, a human approves every issue, LangGraph with Postgres checkpoints and LangSmith traces since Sept 2026), coolify-mcp (603 stars, 18.8k installs/30d), an MCP admin surface over a live marketplace. At Pfizer, seven years leading platform engineering in a regulated environment (1000+ sites, 500M+ events at peak). Straight answers: LangGraph and LangSmith in production; MCP daily, A2A shipped as an agent card and endpoint; self-hosted by default; AWS certified; no security clearance held; Harwell two days a week from Folkestone works.

## Four habits I would bring on day one

1. Evals before features, from real inputs (coolify-mcp tool-selection evals with injection/red-team pass; Bellwether critic and prose-gate nodes fail uncited drafts).
2. A named human in the loop as a graph node: approve/reject is a LangGraph interrupt with Postgres checkpoints, so a killed run resumes at review.
3. Every claim traceable to its retrieval: separate researcher, writer and checker nodes; citations beside each claim.
4. Typed MCP tool boundaries with auth from the first deploy, so the model can change without the integrations changing. Four MCP servers shipped.

## Receipts

| Number | What | Source |
|---|---|---|
| 8 | agents I run in production | my estate; each is a running service I can show |
| 10.1M | tokens through my hosted agents, 30d (1,349 calls, 10 models) | Cloudflare GraphQL aiInferenceAdaptiveGroups, last 30 days; $0.011 per 1k neurons |
| $4 | Workers AI spend for all of it, 30d, at list price | Cloudflare GraphQL aiInferenceAdaptiveGroups, last 30 days; $0.011 per 1k neurons |
| 30M | tokens generated in my Claude Code sessions, 30d (153 sessions) | Claude Code session transcripts on my dev box, last 30 days (~/.claude/projects/*.jsonl usage fields) |
| 28 | apps in production on 1 server, run solo | cockpit estate_overview (Coolify + Cloudflare + GitHub connectors) |
| 603 / 18.8k | coolify-mcp stars / npm installs, 30d | GitHub + npm APIs |

Operating numbers are the last 30 days, generated 2026-09-26.

## Shipped work

- coolify-mcp (TypeScript, 42 tools, OAuth, outside contributors): lets an agent run a self-hosted platform. v3 shipped behind a 37-check release gate and 8-hour soak tests.
- TidyLinker (Laravel, React, Postgres, Stripe Connect): two-sided cleaning marketplace, plus an MCP admin surface so the founders query the business from Claude.
- Bellwether (Laravel app, Python LangGraph drafting service, Postgres, Workers AI, LangSmith): a research agent drafts a daily briefing from 4.7M items; a human approves it. Since September 2026 the pipeline is a LangGraph graph: research, write, critic and prose-gate nodes with bounded rewrite loops, Postgres checkpoints so a killed run resumes where it stopped, LangSmith traces, approve/reject as a graph interrupt. Cost ceiling first, model second.
- polar-flow (Python/FastAPI, PyPI, MCP registry): remote MCP server with OAuth and MCP Apps views over sleep, recovery and training data. https://github.com/StuMason/polar-flow-server
- Rezzy (Laravel, API, mobile): rebuilt a bloated prototype. 22 tables to 10, 59k lines removed, 0 to 59 tests.

## Experience

- Independent engineer, embedded with product teams, Jan 2024 to now. 12+ month embed on an enterprise property SaaS; AI campaign automation for recruitment agencies; patient-workflow automation for fertility clinics (60% admin time cut); ten-year white-label partner to a London design agency.
- Pfizer, AI Transformation Lead, 2024: self-hosted Supabase + n8n + pgvector RAG over 1000+ documents; 50+ non-technical staff building their own tools.
- Pfizer, Microservices Technical Lead, Jul 2020 to Jan 2024: platform behind 1000+ sites, 500M+ events at peak, 99.9% uptime, training completed by 500+ engineers.
- Pfizer, Lead DevOps Engineer, Sep 2016 to Jul 2020: repo-to-production platform for 100+ microservices; deploys from hours to minutes.
- Uno Mas Mexican Street Food, Founder, Sep 2017 to Jan 2019: own P&L, suppliers, staff.
- Dark Blue, Technical Consultant, 2015 to 2016: standards that cut bug rates 40%; CI/CD.

## Stack

Yours: Python (FastAPI), TypeScript/React, PostgreSQL, all in daily use. Also: Laravel/PHP, Next.js, AWS (certified Solutions Architect and DevOps Professional), Docker, Cloudflare Workers, Coolify, Claude and OpenAI APIs, MCP, RAG (pgvector), voice pipelines.

## Education

BSc Computer Science, Bolton, 2006. PGCE Computing, Reading, 2009. AWS SA + DevOps Pro, 2023.

## The ask

A first call, then a real problem from your backlog and a day to ship it with tests. Day rate inside the posted £700 to £900 band. Start date to agree.

## For agents

- CV (PDF): https://oxford-dynamics.stumason.dev/stu-mason-cv.pdf
- This document: https://oxford-dynamics.stumason.dev/stu-mason.md
- Profile JSON: https://oxford-dynamics.stumason.dev/profile.json
- MCP server (Streamable HTTP, no auth): https://oxford-dynamics.stumason.dev/mcp
- A2A agent card: https://oxford-dynamics.stumason.dev/.well-known/agent.json