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{\Large\bfseries Dennis Thiessen, M.Eng.}\par
Bern, Switzerland $\vert$
\href{mailto:dennis@thiessen.io}{dennis@thiessen.io} $\vert$ +41 795 955 585 $\vert$
\href{https://linkedin.com/in/dennis-thiessen}{LinkedIn}

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Research Platform Engineering\\
Citadel Securities\\
Zurich, Switzerland

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26 August 2026

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\textbf{Application for Platform Engineer, Research Platform Engineering}

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Dear Hiring Team,

The posting describes data systems for ingestion, transformation, storage and lifecycle management of large datasets, built so that researchers can work without fighting their infrastructure. That is my day job. At Swisscom I am Component Owner for business-critical Fulfillment ETL -- a distributed system across Oracle, Kafka, Python and Teradata -- and I build the governed data products that analytics and AI teams consume. I carry the data quality and the on-call pager for that estate, which is a different relationship to a system than having built it and moved on.

What draws me to research platform work specifically is that I already build this kind of system for myself. Outside work I built a self-hosted equity signal platform: it ingests daily prices, fundamentals and sentiment, runs a long-only cross-sectional momentum book through scheduled scan and backtest pipelines, and surfaces the gated setups to a dashboard. It is a personal system, not a production service, and I make no claims for its results. But it is the reason I understand what a researcher actually needs from a platform -- fast iteration, reproducible runs, and trust that the data underneath is right -- rather than knowing it only as a requirements document.

I should be straightforward about the shape of my experience: I have built and operated data products and pipelines on a platform, not authored a research platform at firm scale. That step is the reason the role interests me, and the operational judgement I would bring to it is real. I am based in Bern, hold EU citizenship and a Swiss B permit, and need no sponsorship.

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I would welcome the chance to talk.

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Kind regards,

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Dennis Thiessen

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