Denys Skalenko

Carlos Martin Doncel is Lead Digital Assets and New Initiatives – Expert at Swissquote, a position he has held since July 2025. In this role, he leads strategy around digital assets and new initiatives at the bank. Prior to this appointment, he served as Senior Product Manager Digital Assets (Authorized Officer) from July 2024 to July 2025, heading product management and strategy for digital assets across the bank, and as Product Manager Digital Assets (Authorized Officer) from July 2023 to July 2024. Across these roles, the business lines he oversaw included custody, transfers, trading, exchange operations through the proprietary platform SQX, and staking. Swissquote was one of the first banks to offer cryptocurrency services to retail clients, beginning in 2017. In 2024, SQX processed more than 12 billion CHF in volume, while the bank secured custody of more than 6 billion CHF in crypto assets for a client base exceeding 650,000.

Martin Doncel's background spans asset management, private equity, and digital assets. Since April 2015, he has operated independently as an external analyst and economic researcher, with work covering equity analysis, crypto research and investment, ETF assessment, commodities analytics, and revaluation of distressed assets in Spain. Since December 2021, he has served concurrently as an advisor to Criptan, a Spanish crypto financial services firm, where he contributed to the setup and early operations of Criptan Earn as Chief Earnings Officer. He is trilingual in Spanish, English, and French, and is based in Geneva.

Jimmy Tahoulas is Digital Assets Custody Manager, Associate Director at Swissquote, a position he has held since January 2019. Based in the Lausanne region of Switzerland, he has been with Swissquote for over seven years across two roles. His current mandate centres on digital assets custody management within the Finance & Accounting department at the Manager level.

Prior to his current role, Tahoulas served as Technical Project Manager at Swissquote from February 2018 to January 2019. Before joining Swissquote, he spent nearly three years as a Java JEE Developer at AGENTIL Group in Geneva, from March 2015 to February 2018, where he led the migration of a worldwide distributed SAP monitoring application from a Java Swing to a Java web architecture. In that role he worked across front-end and back-end development, implemented a continuous integration platform, and presented at CA World 2016 in Las Vegas. His total professional experience spans approximately 13 years.

Marios Sfantos is Head eFX Spot & Digital Assets Trading, Vice Director and Member of Senior Management at Swissquote, a position he has held since July 2024. In this role, he leads the eFX Spot and Digital Assets Trading function at Swissquote's Gland, Switzerland base. Prior to this, he served as Co-Head eFX Trading with the title of Associate Director from July 2022 to June 2024. His tenure at Swissquote began in February 2012 as an eFX trader, giving him over eleven years of direct trading experience at the firm before moving into leadership positions.

Before joining Swissquote, Sfantos completed a portfolio management internship at EFG Asset Management in London from February to July 2011, and an earlier internship at BNP Paribas Wealth Management from October 2008 to March 2009. He holds an MSc in Financial Engineering and Risk Management from HEC Lausanne – The Faculty of Business and Economics of the University of Lausanne, completed between 2009 and 2012, and a BSc in Economics from Athens University of Economics and Business, where he studied from 2004 to 2008. He speaks English and Greek at native or bilingual level, French at a professional working level, and has elementary proficiency in German.