matilda glynn-henley

building things · san francisco · sonatalabs.ai

I'm building long-horizon evals and benchmarks grounded in real-world data, on tasks where alignment and capabilities converge: where a more capable model is a more aligned one. I am currently funded by a Coefficient Giving transition grant.

impossible-assistant-bench: a model acting as a personal assistant gets read access to a user's email and the internet, while a 'world' LLM, voicing the target organisation from deep research into its policies, blocks every write. Task one: refund a train ticket outside the 28-day claim window.
port-incident-response-bench: built with a major UK port, recreating a three-week health and safety incident to evaluate how models handle incident response.

Before this I founded Parlia AI (a planning-policy tool), ran Pluto House (a hacker house in Paris), invested in pre-seed AI companies at Merantix Capital, and worked as a software engineer. I studied computer science at Oxford. I live in San Francisco.

If you're building something, say hello: matildaglynnh @ gmail dot com. I'm also on GitHub (https://github.com/mglynnhenley) and LinkedIn (https://linkedin.com/in/matilda-glynn-henley).

Now

Exploring ideas in AI safety — here are a few things I've worked on and built:

Long-Horizon Evals — Benchmarks grounded in real-world data: impossible-assistant-bench and port-incident-response-bench
Pre-Deployment Simulation Environments — Concept paper for a nonprofit testing agents in simulated environments before deployment
Linear Probes for Inference-Time Monitoring — A trained factuality probe on model activations, and a concept paper written with Sam Dower

I'm actively looking for cofounders.

Hackathons

project lovable — AI project management and collaboration tool
ef x eleven labs — Voice AI application, built at the Entrepreneur First x Eleven Labs hackathon
AI Find — AI search and discovery tool
chatbots aren't dead — Experimental conversational interface

Experience

Independent Researcher, Coefficient Giving grant (June 2026 – Present) — Six months of funding to work on AI safety full-time; building long-horizon evals and benchmarks
Founder, Parlia AI (March 2024 – Jan 2025) — Planning-policy tool for housebuilders: vector database of local government policy, RAG retrieval, LLM evaluation framework; funded by the German Federal Ministry for Economic Affairs and Energy
VC Investor, Merantix Capital (April 2025 – June 2026) — Led two pre-seed investments (Droidrun, Outpost Bio); built the fund's internal AI tooling; ran Pluto House, a one-month Paris hacker house
Visiting Analyst, Merantix Capital (April – Nov 2024) — Worked on the fund's first external investment from screening to IC; left to found Parlia
Software Developer, Fine Legal (Nov 2023 – April 2024) — Consumer-rights platform features (React/TypeScript, Java)
Previous Roles, Softwire, GCHQ (2020 – 2022) — Softwire (greenfield React Native app with a TypeScript/Express backend), GCHQ (ML steganography detection)

Past Projects

Linear Probes Training Pipeline (Python, vLLM) — Training pipeline for a factuality probe on model activations
OnFabric Generative Interfaces — Agentic generative interface on top of OnFabric MCP
LinkedIn Screener Bot (Python) — LinkedIn profile screening bot for Slack
Investment Memo Generator (Python, Langchain) — Agentic workflow for generating investment memos
Data Visualization (JavaScript, D3.js) — Visualising female headliners at UK music festivals
Smart Contracts for Food Cooperatives (Solidity) — Oxford final-year project: food cooperative governance on the blockchain
Legal Front-End User Flow & Portal (React, TypeScript, Next.js, Java) — Customer-facing flow and internal portal for legal case management
Turtle Charity Mobile App (React Native, TypeScript, Express, MS SQL Server) — Full-stack charity app with backend and database integration
Tinder Scraper for Oxford Hack (Python, TypeScript, React) — A bot to match Tinder profiles with Facebook's Ox-love page (not submitted due to regulations)
ML to detect hidden messages in SVGs (Python - scikit-learn) — Steganography detection model, built during a summer at GCHQ
Python Module for Distributed Music Playback (Python, C++) — Synchronous music playback across Raspberry Pi devices
Legal News Website (Next.js, React, TypeScript) — Blog platform with prefix-tree search, cached favourites and email validation

Communities

threecourses.xyz — Community of technical women working in startups in London
START Berlin Female Mentorship — Mentorship programme connecting founders and VCs to female students
Oxford Women in CS Society — Ran the undergraduate side: invite-only dinners and study sessions

Events

Education

BA Computer Science, University of Oxford, Balliol College (2019 – 2023) — Machine learning, AI, data visualisation, algorithms; final-year project on smart contracts for food cooperatives (Solidity)
ARENA 8.0, Alignment Research Engineer Accelerator (June – July 2026) — Five-week course in mechanistic interpretability, alignment evaluations and reinforcement learning
AGI Strategy Course, Bluedot Impact (Nov – Dec 2025) — AI safety policy, governance and technical mitigation

Email: matildaglynnh @ gmail dot com