AI & backend engineer · Ireland
Nigel Hanlon
Solving problems and learning things.
I build AI systems and the backends they run on. Fifteen years of production software in TypeScript, Node.js and PostgreSQL. These days that means connecting agents to the tools engineers already use, and researching how language models work.
01 · Selected work
Landmarks along the way.
Wiring agents into my team's tools
MCP connectors and skills that take a Jira ticket from spec to review, with people approving every merge and deploy. Now used daily by my team at Contentful.
Tool · Retrieval & MCPAlexandria
A local-first knowledge store that AI agents can search over MCP. Keyword and vector search fused in one portable SQLite file.
Research · AttentionWhere attention breaks
19 experiments that found a sharp failure point in standard attention, and a variant that pushes it out 2×.
2020 · Public healthNational contact tracing
Backend for the COVID-19 exposure-notification apps in Ireland and Gibraltar.
02 · Toolkit
What I work with.
AI systems
- Claude Code, agents & skills
- MCP servers & integrations
- Retrieval: BM25 + vector search
- Embeddings & local LLMs
- Python & PyTorch
- Experiment design & evaluation
Backend & data
- TypeScript & Node.js
- PostgreSQL & PostGIS
- GraphQL & REST APIs
- Redis & Elasticsearch
- SQLite (FTS5, sqlite-vec)
- React
Infrastructure
- AWS
- Kubernetes & Terraform
- CI/CD, Git & GitHub
- Sentry & Datadog
- Incident response
- Linux
03 · Research
Field notes.
Independent experiments on how language models work. I build the controls before I believe a result, and I publish the ones that fail.
- post-mortem
The MambaE answer leak
A state-space model seemed to solve two-hop reasoning. Three controls showed it was reading the answer from the input.
- fast weights
Fast-weight reasoning
Can a cheap recurrent layer chain facts together in one pass without attention? Three chapters map where it breaks, and one training change gets partway through.
- applied ML
Weather nowcasting
Gradient-boosted trees on one station's hourly readings beat the 1920s barometer rule a cheap weather station uses.
04 · The route
Fifteen years, charted.
- 2022-now You are here
Contentful Software Developer
Content-database abstractions on PostgreSQL and performance work, plus the agentic development setup my team uses daily.
- 2021-2022
ENGAGE XR Senior Software Developer
A new Node.js microservices architecture and the move off a legacy PHP monolith.
- 2017-2021
Nearform Full-Stack Developer
Client work for public health, construction, publishing and agriculture, from national COVID-19 contact tracing to hackable conference badges.
- 2014-2017
OpenApp Developer & Systems Admin
Health and geospatial platforms, including An Post GeoDirectory and a patient-data encryption tool.
- 2011-2014
Hanlon IT Independent
The air-ambulance GIS for Health Atlas Ireland, in service for over five years.
- 2008-2009
OpenApp Systems Administrator
Where it started.
05 · Bearings
I grew up on a farm in rural Ireland. My dad was a mechanic, and I spent most of my childhood with oil on my hands and grease under my nails, helping him fix farm machinery. It taught me how mechanical things are designed, how they fit together, and how timing can make or break something. It's also why I took apart so many toys as a kid. I was a menace with a screwdriver.
Our first PC was a Packard Bell with a 166MHz Pentium and 8MB of RAM. I saved up for my own, built websites in Word, and then my cousin dropped off a big heavy book called Corel Linux. I installed it and made a huge mess of my PC. Linux back then had no safety rails, but you learned either way. Those nights at a glowing screen well past midnight, feeling triumphant when hello world compiled, are still how I learn.
Richard Feynman said "What I cannot create, I do not understand." That's my brain in a nutshell. I want the why underneath things, and I get there by taking the thing apart and building it again, hopefully a bit better.
I'm autistic, so I don't see the world like most people. Everything is the sum of different parts working together, be that nature, code or the thoughts in our heads. Understanding the world helps me understand myself.
06 · Talks
On stage.
07 · Contact
Building something with AI, or want to talk shop? Email me. I read everything.