Staff, Fraud Countermeasures

Build something people love Wealthsimple is Canada’s leading financial innovator. The company offers a full suite of simple, sophisticated financial products across managed investing, do-it-yourself trading, cryptocurrency, tax filing, spending and saving. Wealthsimple currently serves more than 4 million Canadians and holds over $155 billion in assets under administration. The company was founded in 2014 by a team of financial experts and technology entrepreneurs, and is headquartered in Toronto, Canada. We're proud of what we've built — and we're just getting started. Read our Culture Manual and learn more about how we work . About the team The Fraud Countermeasures team is part of Data Science, and it's how Wealthsimple grows safely. We balance fraud losses with client friction, so legitimate clients can use their money without jumping through hoops. We work in small pods that pair a fraud countermeasures lead with a data scientist and an analytics developer, and we sit alongside Product and Engineering on every new feature launch. We use data to make every decision, and we use AI tools to move faster. If you want to work on hard problems with people who care about craft, you'll fit right in. About the role Card fraud is one of the highest-stakes problems at Wealthsimple, and this role owns the strategy for it. You'll set direction for how we prevent application, transaction and account takeover fraud across our card products, and you'll do it independently, with real accountability for the outcome. This is a Staff individual contributor role with manager-level impact: you'll lead through expertise and influence, not direct reports. It's open to candidates in any timezone in Canada. What you'll do Own fraud strategy and execution across application, transaction and account takeover fraud for Wealthsimple's card products. Manage the card fraud loss budget as our volumes grow, and guard against the fraud attacks that can blow a budget up. Design, backtest, ship and tune detection rules, and set decision thresholds on ML risk scores. Weigh fraud losses prevented against operational cost and client experience before you recommend an approach. Partner with Product and Engineering to build controls that stop fraud without blocking legitimate clients, like step-up authentication instead of a hard decline. Guide the data scientists and analytics developers in your pod, and mentor junior teammates on strategy, rule building and problem-solving. Skills you bring 6+ years of experience in fraud prevention, including 3+ years working directly on card fraud (prepaid or credit) at an issuer, fintech or payments platform. Hands-on ownership of card fraud strategy across application, transaction and account takeover fraud. Advanced SQL. You write complex queries against transaction-level data yourself, without waiting for an analyst to pull it. A track record of building, backtesting, shipping and tuning fraud rules, and explaining the precision, catch rate and approval rate impact of each. Experience quantifying fraud savings against operational and client experience costs to make a clear recommendation. Experience using AI tools in your daily work, and examples of where they changed your output. The ability to influence Product, Engineering, credit risk, operations and external vendors toward a decision without direct authority. Clear communication with technical and non-technical audiences, including senior leadership. Nice to have: Knowledge of Visa and Mastercard network rules, dispute processes and chargeback rails. Who you are You set direction on your own and take ownership over outcomes for your space, from fighting fraud attacks to minimizing client friction. You make decisions with numbers behind them, and you're honest about what the numbers can't tell you. You lead through influence. You can get a roadmap conversation to go your way by rallying others around shared