thewhisk.dev

William Smallman-Köpf

Software Engineer

📍 Barcelona · ✉ william@thewhisk.dev · 📞 +34 607 043 373 🌐 william@thewhisk.dev · github.com/wismko · linkedin.com/in/wismko

Native English Speaker · Eligible to work in EU & UK

Profile

Software engineer building cloud-native systems in high-ownership environments. At PhoenixNAP, became the internal go-to for Temporal workflow systems with contributions adopted across the engineering organisation. Comfortable owning implementation end-to-end on greenfield microservices, working directly with customers, and presenting technical work to internal and external audiences.

Experience

Software Engineer — Sage, Barcelona

October 2025 – Present

  • Initiated a technical debt reduction initiative to address quality issues, aligning it with the team’s move toward AI-native development practices.
  • Appointed AI champion for the team; led a cross-team hackathon focused on building AI capability across engineers rather than individual output.
  • Co-launched an AI engineering blog with the Director of Engineering for Network Services.
  • Driving adoption of agentic tooling in team repositories, starting with a test analysis agent that validates test quality against the engineering handbook.

Software Engineer — PhoenixNAP, Malta

June 2022 – September 2025

  • Proposed and implemented a Temporal replay testing approach that eliminated incompatible workflow histories. Adopted company-wide and promoted by engineering leadership as the standard pattern.
  • Owned implementation design and delivery of a high-priority Google Ads integration microservice, partnering with a senior engineer on architecture and shipping on schedule.
  • Led the extraction of accounting logic into a dedicated microservice, improving system modularity and streamlining invoicing and payments flows.
  • Recognised internally as the team’s Temporal expert; ran knowledge-sharing sessions and onboarding for other engineers.
  • Received the maximum available salary increase in each annual review, including one out-of-range increase recognised as exceptional by engineering leadership.

Full-Stack Developer — Colonel Duck, Birmingham

May 2021 – May 2022 · Sole developer from June 2021

Colonel Duck built PreEnrolment, enrolment training and data onboarding software for construction companies.

  • Hired to replace two departing developers; became the sole developer within six weeks and took full ownership of the product across frontend, backend and customer-facing work.
  • Maintained and extended the platform for an existing B2B customer base and helped onboard a new customer during my tenure.
  • Worked directly with customers to scope and deliver features, handling the full cycle from requirements through deployment and support.

Selected Projects & Community

  • Unwave Network — Personal project inspired by record collecting, exploring music-adjacent software tooling. (unwave.net)
  • MEIA — Memberships & Payments (Freelance, 2025) — Built memberships and payments functionality for the Malta Entertainment Industry and Arts Association.
  • EdX Bootcamp Teaching Assistant (2022) — TA for a React bootcamp; supported students through coursework and projects.
  • Lykelli (Volunteer, 2021) — Contributed to a non-profit building technology to improve wellbeing.

Skills

Languages & Frameworks: Java 21, Spring Boot Distributed Systems: Temporal workflows, RabbitMQ, REST APIs Data: MongoDB, PostgreSQL, MySQL Delivery: GitLab CI/CD, unit & integration testing Architecture: Cloud-native microservices, event-driven systems

Education

Diploma of Higher Education — Computing & IT Open University (UK) · 2012–2016

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