I build pricing and risk engines at BNP Paribas, and products of my own.
I’m the team’s only C# engineer, and the engines run on CPU and GPU. I’ve won the bank’s digitisation competition and a Take Ownership award.
The engines run large simulation-based calculations across several asset classes. Illustrative paths, not real prices.
The same tests had to run on both CPU and GPU.
Winner. Digitisation · 2025. Led a team of four to win the bank’s digitisation competition, co-building a dashboard that cut a 30–40 minute data load to under 5.
Take Ownership · _nology · Q1 2026 · awarded May 2026
Work
History, then marketing, then code. Each move was towards the work I liked most.
Winner. Digitisation · 2025 Take Ownership. Q1 2026 AI Champion. 2026 I was nominated as an AI Champion, and the workflow I built is now used by several teams across the department. With that workflow I integrated a pricer in a couple of days, a job that takes an experienced engineer about two weeks.
Page load, cut by 40%. Cut page load by 40% by refactoring React components and lazy-loading assets. Key API p95, 520 ms → 230 ms. Added indexes and rewrote slow queries, starting with the API that mattered most. Mobile retention, up 30%. Fixed mobile layout and browser bugs found by a cross-browser testing pipeline.
Core Web Vitals pass rate, 62% → 88%. Scoped performance fixes with the engineers and ticketed them. p95 page load, cut by 30%. The same scoped, ticketed fixes. Where the switch started. The best part of the job was working with the engineers who built our website.
- History at uniBefore 2021 · Because I loved it, and I still do.
University of Essex. Diploma of Higher Education, History. Jul 2021.
Where I’m headed
Building a whole product well: what to make, why it works, and getting it to production. How far I’ve got on each.
- Knowing what’s worth building.Judgement
So far, Optegra. At Optegra, split tests and dashboards guided what the engineers built next.
- Knowing why it works, not just that it does.Depth
So far, BNP Paribas. Six months from zero C# to production code, in a pricing engine of around 70 projects.
- The whole way, from idea to running in production.Range
So far, Threshold. Threshold, from 57 user stories to a live site.
Things I make
Products of my own, from a rental calculator to a risk simulator.
Product · Data visualisation · 2026
Event-driven systems · 2026
Offline-first interaction · 2026
Prototype · 2026
Systems · API · 2025
AI product · 2025
How I work
Four habits, and where I picked them up.
- Start from a real problem.Threshold started because my friends had no clear idea what renting would cost by area. Flowtime started because Pomodoro kept cutting me off mid-flow.
- Write it down first.Before I build, I write down the problem, who it’s for, and what’s out of scope. Threshold had 57 user stories before any code.
- Ship it so it’s safe to undo.At BNP Paribas, taking a stale data dependency out of live pricing, I put the new path behind a feature flag that defaults to off, with caching and an end-to-end test nobody had asked for.
- Measure whether it works.I learned this in marketing. At Optegra, split tests and analytics dashboards showed which changes brought in consultations and guided what the engineers built next; consultation conversion rose by 15%.
- Threshold’s PRD16 April 2026
People in their 20s and 30s make the decision to move out … without a clear, honest view of what it will actually cost. Threshold’s PRD, 16 April 2026
Off the clock
What my own time looks like this week.
- My training week
Monday: Full-body gym. Tuesday: Zone 2 run. Wednesday: Full-body gym. Thursday: Interval run. Friday: Full-body gym. Saturday: Zone 2, rower or bike. Sunday: Assault bike intervals. Out on a run, central London.
GitHub, the past year
1,804 contributions in the past year · Live from GitHub
Use the arrow keys to move between days.
Cover of Dark Age by Pierce Brown
Admit one. Poster for Kiss Kiss Bang Bang (2005)
- Odd but true, from this week in history3 things that happened this week, some stranger than others. · Live from Wikipedia
1 of 3. 26 October 1921. The Chicago Theatre (pictured), the oldest surviving grand movie palace, opened. 2 of 3. 26 October 1377. Tvrtko I is crowned the first king of Bosnia. 3 of 3. 26 October 1863. The Football Association is founded.
Personal site for Elias Bennett: the work, how I build it, and what I do off the clock. Next.js, Playwright-tested.
