Building 3 ventures · open to the right role
I build backend-heavy products — with the maths to back them.
Engineer and KTH applied-mathematician specialising in backend systems, automation, and quantitative work. Three early-stage ventures with live users, plus ongoing contract work.
Who I am
I treat software engineering as both my work and my passion. As far back as I can remember I have been dreaming of building — of shaping my ideas into something real. The first was an on-demand thesaurus I wrote when I was 13.
I have grown that repository of projects immensely since, and I am open to engagements involving exciting, forward-facing software and business ventures.
This site was built as both an information source and a display of my work, for anyone who is interested.
— Elliot Hegraeus
A generalist's toolkit, with depth where it counts.
Backend & automation — Scheduling and sync engines, services, and the automation that makes systems run themselves — Go, Rust, Python, Postgres.
Quantitative — Monte Carlo, regression, optimisation and stochastic modelling — built into real tools, not just coursework.
Shipping products — Taking startups end-to-end: from data model and billing to the interface real users actually touch.
Quantitative
Monte Carlo, regression, optimisation and stochastic modelling — built into real tools, not just coursework.
Work experience
Where I've shipped real systems.
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Incoming — consulting engagement · International hospitality group
2027Brought in through referral to advise a major international hospitality brand; scoping with leadership in 2026.
Read more -
Product engineering · Habitat 10
2025Built the Habitat 10 site on Next.js / React — now the top organic result and the cited source in Google's AI Overview for the development.
Read more
Ventures
Startups, not side projects.
Three early-stage companies I'm actively building — each with live users or co-founders, and a backend-heavy core. Scroll through them.
Live · native in development
Quartz
A scheduling platform with live users — production web app, native app now in development.
- Next.js 16
- React 19
- FastAPI
- Tauri 2
In beta · launching 15 September 2026
Rebook
A reading startup with a subscription & delivery engine — in beta, launching 15 September 2026.
- Next.js 15
- PostgreSQL
- Google Cloud
- Stripe
Active · co-founded · pitching at conferences
Lootit
An esports micro-betting startup I co-founded — live, and out pitching at conferences.
- Next.js 15
- Express
- PostgreSQL
- Redis
Projects
Where I sharpen the tools.
Research, quantitative engines, and systems work — the projects where I go deep on the maths and the backend. Scroll through them.
Quaternion Relativity
Treating the quaternion group under addition as a dual space to relativistic effects — and predicting spirals.
- Python
- NumPy
- SciPy
- Matplotlib
Document Model
AI contract analysis with a Monte Carlo engine for probabilistic risk assessment.
- Python 3.13
- FastAPI
- OpenAI GPT-4o
- NumPy
Shazam Clone
Audio fingerprinting that identifies songs from a library of 1000+ tracks.
- Python
- librosa
- NumPy
- SciPy
Complex Model
A Rust + Python engine for stock simulation via RK4/Euler solvers and Monte Carlo volatility.
- Rust
- Python
- NumPy
- Pandas
Cache Engine
A low-latency key–value cache: a Rust core driven from TypeScript over a binary buffer protocol.
- Rust
- TypeScript
- Node.js
- serde
FastType
An Obsidian plugin for faster writing — I use it every day.
- Python
- OpenAI
- Obsidian
Split Keyboard
A custom split Corne keyboard: ZMK firmware with Dvorak, home-row mods, and 8 layers.
- ZMK
- Zephyr RTOS
- Device Tree
- GitHub Actions
Availability
Available for contract & consulting work
I take on freelance and contract engagements as a backend and quantitative engineer — building services, automation and data tooling in Go, Rust and Python. Based in Stockholm, working remotely across Europe, in English or Swedish.
- Contract backend engineering
- Automation & internal tooling
- Quantitative development
Profile
I build backend-heavy products and have the mathematics to back them. KTH applied-mathematician (the most selective program in Sweden) running three early-stage ventures with live users, alongside ongoing client work. I specialise in backend systems, automation, and quantitative engineering — and I learned the stack the hard way before I ever leaned on AI to ship faster.
Best matches
Where I add the most value:
- Backend / API engineer
- Quant / ML-adjacent engineer
- Automation & systems
- Founding / early-stage engineer