Harry Day

Software engineer · London, UK

I build software to solve problems. Interested in highly performant, and distributed systems. Currently working at UBS building a next-generation Asset Management platform.

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Personal projects


SongLinkr ‐ An iOS application that converts music links between streaming platforms so you can open them wherever you actually listen. Built natively in Swift using SwiftUI. Achieved over 4000 downloads through word of mouth advertisement.

2021 – Present
Swift · SwiftUI

Omni ‐ a proof-of-concept platform for Computer Science students and junior engineers to showcase personal projects. Architected to scale from zero to a million users globally overnight, through the magic of Kubernetes. Built using multiple Go microservices, serving a beautiful front-end using HTMX, TailwindCSS and AlpineJS; backed by a data layer designed for sharding from the start.

2024
Go · HTMX · Kubernetes

Gentle Ghosts ‐ a generative art collection of 5,000 unique pixel-art ghosts, each built from a randomised set of traits. The generation pipeline was written in Python; the downscaling in Node.

2022
Python · Node

Experience


UBS ‐ Trading & Execution Services Software Engineer. Building performant, distributed systems for a scalable, digitial and highly-automated cross-asset portfolio management and trading platform which allows Investment professionals to operate efficiently. Maintaining and iterating on backend microservices which power front-to-back order management and pre-trade compliance. Collaborating with stakeholders, QA testers and other developers, ensuring platform stability and reducing risk.

2025 – Present
Kafka · Kubernetes · .NET

Novlr ‐ Software Engineer. Maintained and supported an online writing platform used by hundreds of thousands of authors worldwide. Rewrote and modernised the platform with a small team of UX designers, engineers and writers to enhance stability and enable the development of exciting new features.

2024 – 2025
React · MongoDB · TypeScript

UBS ‐ Industrial Placement, Asset Management Technology. Focused on developer experience and architecture as part of the platforms team. Estabilished shared GitLab CI/CD pipelines which enable consistent, reproducible build processes and ensure a Secure Build Chain (SBC). Wrote inner-source libraries used by production-critical applications, standardising the ways that applications interact with Kafka.

2023 – 2024
GitLab CI/CD · .NET · GraphQL

University of Manchester ‐ BSc Computer Science. Treasurer of the Motorsports Society. Studied the fundamentals of Computer Science and Software Engineering with a focus in my final year on distributed systems. Authored a dissertation titled "Building a Social Media Platform Capable of Scaling to a Million Users Overnight", exploring the architecture behind social networks and how to handle rapid user growth. Produced a proof-of-concept platform, Omni, to explore the ideas in my dissertation.

2021 – 2025
C++ · Python · Java

Elsewhere