Sebastian Southwell
Multidisciplinary Software, Systems & DevOps Engineer Cloud · Software · AI · Hardware

Who am I?


Sebastian Southwell

I'm Sebastian Southwell, a multidisciplinary software and systems engineer with a First-Class MComp in Computer Science from the University of Sheffield. Currently a DevOps Engineer at the UK Home Office, I build reliable, scalable systems and am particularly interested in platform engineering, applied AI and proof-of-concept development. My academic work includes leading master's-level research into reducing hallucinations in large language models and shaping the design and strategy of a start-up development project.


Outside work, I've contributed to a wide range of projects and technical communities. I won prizes at HackSheffield 7, 8 and 9 and held several university leadership positions, including Technical Systems Officer, Technical Events Officer, Inclusions Officer and Lead Imaging Systems Engineer for a student-led UAV project.

I'm also active in the Sheffield community, have been partner dancing for two years and competed at IVDC Blackpool in 2025.

Roles


UK Home Office

DevOps Engineer (SEO) Dec 2025 - Present

Leading migration of the team's development environment between Cloud IDEs — experimenting with and implementing a solution alongside a cloud platform representative. Onboarding various new applications into our primary infrastructure, configuring them and proving value while working closely with stakeholders.

Associate DevOps Engineer Feb 2024 - Dec 2025

Implemented a PrivateLink for high-traffic network infrastructure, reducing unnecessary data transit. Built dynamically reproducible, interconnected networks with Terraform and Packer at the request of an internal team, ensuring fit for requirements and developing a proof of concept. Created permission-auditing scripts to help enforce a zero-trust policy across our services and team resources. Sat on interview panels and mentored junior engineers.

Apprentice Developer Sept 2022 - Feb 2024

Working with a senior engineer, built an autoscaling data forwarder handling 2,000+ events per second. Produced a VPN connection automation script that reduced on-device connection and setup time for engineers. Contributed to a government backend project modernising certificates and records, working with QA and following quality review processes.

Academic Experience


The University of Sheffield

Master of Computing (MComp), Computer Science Sept 2020 - Jun 2025

First-Class MComp graduate whose degree centred on three major projects:

  • Darwin (BDUK) — System Architecture lead on a graph-verified RAG assistant mitigating hallucinations in multi-modal LLMs, built for government body Building Digital UK (74%).
  • Dissertation — a physical smart-home voice assistant on the University of Sheffield's unPhone hardware platform, combining LLMs, speech processing and IoT, supervised by Professor Hamish Cunningham (78%).
  • Genesys — a Ruby on Rails career-guidance platform for University of Sheffield spinout epiGenesys, covering the full product lifecycle from customer interviews, personas and pain-point/experience mapping through to a business model and the build itself — praised for its testing, security and performance engineering (75%).

Alongside the technical curriculum, Finance and Law for Engineers (88%) covered financial statement literacy (income statement, balance sheet, cash flow), UK company law and audit regulation, and pricing strategy grounded in demand economics — the commercial and legal literacy behind the engineering.

Aquinas College, Stockport

A-Level: Computer Science, Maths, Physics, EPQ (Social Engineering) Sept 2018 - Jun 2020

Portfolio


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Certifications, Awards & Degrees


AWS Certified Cloud Practitioner Foundational certification covering core AWS services, cloud architecture and security best practices. CLF-C02 2024 – 2027

Extracurricular


Partnered Dance

Latin & Ballroom, Salsa and Bachata.

Competed in Latin & Ballroom at Blackpool, plus social dancing across all three styles: footwork, frame, connection and musicality. Regularly attending community events.

Technical Reels

Making short technical/coding reels on Instagram. Quick explainers and builds in bite-sized video form, alongside occasional travel vlogs. @seb.not.found

Improv Comedy Jams

Attending regular improv comedy jams, of which the initial objective was to improve public speaking, quick-thinking improvisation and build character.