King's College London MSc Theoretical Physics Full-Stack Developer

I build things with physics, maths & code.

I'm Daniel, a physics graduate and full-stack developer. I enjoy working across scientific modelling, data analysis, and web development to create solutions that are both functional and visually appealing.

01 / Selected Work

Built. Tested. Deployed.

A Few Things I've Built.

Below are some of the projects I've worked on, showcasing my skills in software development, data analysis, theoretical physics, and scientific modelling. Each project reflects my commitment to pursuing excellence in my work and creating solutions that are both effective and visually engaging.

01 / Software Engineering

Expendid

Finance software for freelancers

As Lead Web Developer / Software Engineer, I developed extensive Flask back-end functionality, authentication, analytics, pricing, referral and waitlist flows, email automation and responsive front-end architecture.

Role
Lead Web Developer / Software Engineer
Stack
Python · Flask · JavaScript · Git
Focus
Functionality · Analytics · UI/UX
Period
Sept 2025 — Jul 2026
website / product
Expendid dashboard — dark theme Expendid dashboard — light theme
02 / QUANTUM COMPUTING

QAOA for Max-Cut.

Quantum optimisation · Qiskit

I implemented the Quantum Approximate Optimisation Algorithm (QAOA) for the Max-Cut problem in Python using Qiskit, explicitly constructing the variational quantum circuit and classical optimisation loop rather than relying on a black-box implementation.

I compared COBYLA, SLSQP and Powell across complete and sparse graphs, examining convergence, approximation quality and the effect of increasing circuit depth. Powell was the strongest and most consistent optimiser in my experiments.

Problem
Solving Max-Cut with QAOA
Framework
Python · Qiskit · SciPy
Study
Optimiser efficiency · topology · circuit depth
Module
Modern Computational Techniques for Theoretical Physicists
quantum optimisation / max-cut
K10 · p = 2 · approximation ratio
Powell
≈ 0.98
COBYLA
≈ 0.93
SLSQP
≈ 0.78
03 / COMPUTATIONAL PHYSICS

Electro­magnetic Resonance Simulation.

Finite-Difference Time-Domain (FDTD) solver

I developed a custom 2D FDTD electromagnetic simulator in Python for dielectric ring resonators: implementing Yee-lattice updates, designing Gaussian-tapered Absorbing Boundary Conditions (GABCs), sweeping resonator radius and analysing resonant modes, Free Spectral Range and Q-factors.

Method
Finite-Difference Time-Domain
Language
Python
Output
Resonant modes · FSR · Q-factor
Result
First-class Project Grade
simulation / field intensity
2D Yee latticering resonator|E| field
04 / QUANTITATIVE RESEARCH

Options Pricing · Risk

Pricing, portfolio construction & risk

During my quantitative research internship at Perbak Capital Partners, I worked with Black-Scholes and binomial option-pricing models, non-normal return distributions, volatility analysis, market-neutral strategy and convex optimisation of market-neutral portfolios.

Models
Black-Scholes · Binomial
Optimisation
CVXPY · Market-neutral Portfolios
Data
Financial Time-series
Tools
Python · NumPy · Pandas
model / efficient frontier
PORTFOLIO OPTIMISATIONrisk → return
max Sharpe VOLATILITY / RISK EXPECTED RETURN
efficient frontier• candidate portfolios
02 / Other Builds

Over the years

A Selection of Other Projects I've Built.

01 This portfolio website HTML · CSS · JavaScript · SEO · Flask ↗
02 MovieRank Pro Flask · CRUD · SQL · Bootstrap5 · WTForms +

Movie ranking website I created for day 64 of Angela Yu's 100 Days of Code course on Udemy.

Movie ranking website homescreen
03 Restaurant Website Flask · JavaScript · CSS Grid +

Beautiful and functional booking site designed and built for a high-end restaurant. See my web development portfolio for more pictures.

Restaurant website homescreen
04 Catholic Blog HTML · CSS · Encryption · Databases ↗
05 Flashcard App Python · Tkinter · Flask +

Fun little flashcard app that I built to help me as I studied for my HSK 5 (C1) Chinese exam. It is complete with a database, local memory, the required vocab list, text to speech and more. You can see an earlier version of the programme on my LinkedIn.

Flashcard app
06 Parish Website Flask · JavaScript · Responsive UI +

Reverent parish website with full functionality and a beautiful design. See my web development portfolio for more pictures.

Parish website homescreen
03 / Toolkit

Tools I have acquired

What I Reach For.

Languages & Markup

  • Python
  • JavaScript
  • SQL
  • Dart
  • GDScript
  • MATLAB
  • Wolfram Mathematica
  • HTML / CSS

Data & Scientific

  • NumPy / SciPy
  • Pandas
  • Matplotlib / Plotly
  • Seaborn
  • scikit-learn
  • CVXPY
  • Qiskit
  • TensorFlow

Build & Automation

  • Flask
  • Flutter
  • Godot / Pygame
  • REST APIs
  • Selenium
  • Beautiful Soup / Requests
  • Authentication
  • SQLite / PostgreSQL

Tools & Methods

  • Git / GitHub
  • Jupyter / Colab
  • PyCharm
  • Bash
  • Deployment Workflows
  • FDTD
  • Optimisation
  • Regression / Time-series
04 / Future Builds

Projects currently under development

Projects Currently Underway.

01 Traditional Catholic Prayer App Flutter · Dart 2027 +

Oremus is a Traditional Catholic prayer app for people who want orthodoxy in their Faith. It includes a traditional catechism, Thomistic answers to common questions, current and historical codes of Canon Law, the Liturgy of the Hours, and a step-by-step guide to serving the Traditional Latin Mass.

Built in Flutter and Dart — release planned for 2027 on iOS and Android.

Calendar
Roman calendar per the 1960 rubrics / 1962 Missal
Prayer
Parallel Latin & English prayers with Chapel mode reader
Discipline
Fast & abstinence across four disciplines — 1983, 1962, 1917, and the pre-1917 sources that preceded codification
Mass
Missal, Ordinary, and a server trainer with practice & serve modes
Confession
Private examination of conscience — traditional Act of Contrition
Search
Across every prayer, catechesis, canon and spiritual tract
Oremus app — dark theme preview Oremus app — light theme preview
02 Samurai Kingdom Godot · GDScript 2027 +

Samurai Kingdom is a 2D pixel-art strategy and action game set in a fantasy interpretation of feudal Japan. Players build and expand their own shogunate, recruit armies of samurai, rōnin and other warriors, and defend their settlement from rival ninja clans during nightly raids.

Currently in development using Godot and GDScript, with an eventual release planned for iOS and Android in 2027.

Samurai Kingdom — 2D pixel-art game preview
03 Investigation of Quantum Topological Code Python · Qiskit · TensorNetwork · Quantum Error Correction Summer 2027 +

My MSc dissertation with Dr Po-Shen Hsin at King's College London will examine topological quantum codes — the error-correcting structures that make fault-tolerant quantum computation possible. It will cover stabilizer and CSS codes, the surface and colour codes, and the theory of error correction and decoding. The latter half extends the framework to cluster states and measurement-based quantum computing, with the aim of constructing codes and optimising their properties.

I will be writing my dissertation from Jun 2027 — Sept 2027.

05 / About

A little context

Physics, Coding & Everything Between.

I'm a physics graduate who loves to code, solve problems and build cool things. My goal is to continue learning and growing as a software developer with the aim of doing research in quantum computing.

When I'm not coding or studying physics, I love going to Mass and learning about my Faith (Catholicism). I am also an avid martial artist and thoroughly enjoy training and competing. You can follow my mixed martial arts (MMA) journey on Instagram.

Portrait of Daniel English-Brown
Daniel English-Brown London, UK
Current

Theoretical Physics & Software

Building web products, scientific tools, and indie games. Goals: conduct research in quantum information and computing.

Mentoring & Teaching

STEM Tutoring

Private tutoring, STEM outreach, and mentoring the Girls' Robotics Challenge team of 8 to build a BBC micro:bit robot.

Education

King's College London

MSc Theoretical Physics, BSc (Hons) Theoretical Physics, King's College London. Languages: English, Mandarin, French.

Hobbies

Beyond Work

I am an avid martial artist and love (attempting) fine art and going on hikes.

06 / Testimonials

References

What People I've Worked With Say.

07 / Contact

Get in touch

Let's Work Together.

I'm always interested in challenging software, scientific-computing and quantitative projects, or simply meeting people working on interesting problems. If you have something you'd like built — a product, a tool, a game — I'd be glad to hear about it.

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Based in London · Usually replies within 24 hours