Ofir is a seasoned entrepreneur and data scientist by training, Ofir brings a rare blend of deep technical expertise and sharp business acumen to the companies he builds.

Prior to founding Justt, Ofir founded and led Shopial, a social commerce platform that helped merchants seamlessly extend their online presence to social networks. Shopial was acquired by Magento Commerce and later became part of Adobe. His success in building and scaling eCommerce technology solutions has made him a recognized leader in the intersection of AI, data, and online retail.

With over a decade of experience in senior leadership roles across the tech industry, Ofir is known for building high-performing, cross-functional teams and executing bold strategies that drive growth. His background as a data scientist gives him a unique perspective on product and innovation, enabling him to turn complex problems into scalable, user-centric solutions that deliver measurable impact.

Roenen Ben-Ami is a payments and chargeback industry expert and entrepreneur. At Justt, as the Co-Founder and Chief Risk Officer, he has been responsible for the product vision of the company since it was founded. In his previous role at Simplex (acquired by Nuvei), Roenen built the Chargeback and Merchant Risk teams that successfully recovered millions of dollars a year.

Sarah is the Senior Director of Payment Processing & Fraud Strategy at Super.com. She built Super.com’s fraud program from scratch as the company evolved from a merchant (online travel agency) to also issuing a secured card. Prior to Super.com, she specialized in Sarbanes-Oxley (SOX) compliance for new public companies. She is a Certified Payments & Fraud Prevention Professional (CPFPP).

Dwayne Gefferie has established himself as an entrepreneur, investor, advisor, and payments & data science consultant.

Using his 20+ years of experience in Payments, Data Science & Analytics, he has provided insights to companies including ING Bank, Spotify, Facebook, Uber, and Google.

As well as developing global payments provider Adyen’s Acquiring, Analytics, and Data Science capabilities, leading to their successful €20 Billion IPO in June 2018.

He has also served as Dimebox’s Head of Data, acquired by Verifone. And was the VP of Data Science and Analytics at Checkout.com, helping raise Europe’s largest Series A.

For over 5 years, Dwayne was the Co-Founder and Principal Consultant of DataBright, a Data Science & Analytics Consultancy based in Amsterdam and London, which helped enterprise companies develop and execute strategies around Data and Payments, including Nike, Vodafone, RyanAir, and Asos.com. In 2023, DataBright was sold to a Data Aggregation company.

Currently, Dwayne provides selective Advisory and Consulting services to exclusive clients in Payments through the Gefferie Group. He is the author of Payments Strategy Breakdown, a weekly in-depth Strategic Payments Newsletter, read by over 7000 Payments Professionals weekly.

With more than a decade of dedicated experience in the payments industry, Kimberly Singleton has cultivated deep expertise in disputes and chargeback management. Her professional journey began as a Chargeback Advisor, laying a strong foundation for subsequent roles in collections, bankruptcy processes, and business analysis. Progressing into production support before advancing to Product Management. Kimberly has consistently drawn upon her comprehensive background to deliver innovative solutions. Today, she specializes in designing and implementing dispute management and resolution products that not only address industry challenges but provide merchants with tools to effectively and efficiently manage disputes.

Robbie is a payments professional spearheading digital payments optimization efforts at CMSPI, with a particular focus on mitigating fraud and enhancing customer experience through payments. He is heavily involved in merchant advocacy within the industry, sitting on the Merchant Risk Council’s APAC Advisory Board, community committees, and regulatory working groups across a number of initiatives such as the Payment Services Directive in Europe.

Brian Davis is a fraud prevention leader with over a decade of experience building and scaling fraud programs across fintech, e-commerce, and marketplaces. In his current work, he advises fraud vendors and operators on strategy, tooling, and program maturity, while through The House of Fraud he equips experts with intelligence and strategies to become impactful leaders.

Orly Amrany is a seasoned Product Executive with over 25 years of experience in the technology sector, specializing in eCommerce and online payments. Before joining Justt as their Chief Product Officer, Orly led the Premium division at Wix (NASDAQ: WIX) as General Manager and VP of Product, playing a key role in the company’s IPO and its subsequent growth. Her extensive experience also includes executive positions such as Chief Product Officer at Convergin (acquired by Oracle), Chief Product Officer at Natural Intelligence and CPO of PayKey. Advisory board of Fiverr and Monday.com on payments for several years.

Coming from an economics background, Jamie George has been with Ravelin for over eight years. Earning his stripes in Sales initially, he launched and managed both the Account Management and Partnerships teams at the AI-native fraud & payments company. Today, he serves as VP of these teams, working tirelessly and strategically to support Ravelin’s clients and partners to tackle fraud and risk across the entire customer journey.

Karlynn has been with Sunbit for over 5 years and currently serves as a Customer Resolution Manager. Her background includes experience in banking and payday lending, which has given her a strong foundation in customer support and financial services. Karlynn is passionate about compliance, and enjoys finding new ways to improve processes to make work smoother for both teams and customers.

Maisa Breve, vio.com: Maisa is Customer Operations Manager at vio.com. She joined when the support team was just 8 members and helped build the operation from the ground up. Over time, she expanded into the finance side of customer support, creating and tracking processes to strengthen dispute handling. With the team now prioritizing disputes, her efforts are delivering strong results.

Shahar leads Justt’s global R&D efforts including our product development, infrastructure, data science and security. He is a seasoned tech executive with over 19 years of experience in various tech industries. Prior to Justt, Shahar led the technology division at Selina (NASDAQ: SLNA), one of the fastest growing hospitality startups in the world as their Senior VP of Technology. Prior to Selina, Shahar worked at 888 Holdings (LSE:888), one of the largest online gambling companies, as their B2C Chief Technology and Innovation Officer.

Barbara is a Fraud & Dispute Strategy Manager with 15+ years in risk management and compliance, specialized since 2016 in payment operations, fraud prevention, and dispute management. Skilled in scalable strategies, KPI optimization, and international collaboration.

Will has been involved in the travel industry for over 20 years – first as a tour operator and then owning a DMC in Oman, before setting up Trust My Travel in 2011, with the sole task of providing a financially protected payment solution to travel companies around the world. Will is passionate about both the travel and payments industries and how they can integrate with one enough and work seamlessly together for the benefit of all players, from customers to merchants; suppliers to acquirers and insurers.

As Trust My Travel has expanded into Trust My Group Will and his team have looked closer at all the risk components in travel payments and the mitigations and protections that can be put in place to protect the entire sector as comprehensively, but as cost effectively, as possible. Data and technology sits at the heart of everything the group does and Will is a strong advocate for this being the driving force in enabling travel companies, insurers, acquirers and schemes in being able to make informed risk decisions.
When he is not thinking about travel payments and how he can better support the ecosystem, Will loves travelling the world, and getting under the skin of new places, with his family.

Dave is a Principal Technical Program Manager at Microsoft, leading cross-functional initiatives in risk, payments, and commerce. With deep expertise in chargeback operations, dispute resolution, and fraud prevention, Dave drives strategy and execution across engineering, operations, and finance. Known for delivering scalable, AI-driven solutions and strong program governance, Dave focuses on reducing financial exposure while enhancing customer experience.

Ami Patel is the Vice President of Ecosystem Risk Engagement and Advocacy at Visa Inc. Known for her transformative leadership, she has helped revitalize businesses, fortify risk management, and enhance customer experiences throughout her career. During her 25-year tenure in payments, Ami has held various roles across consulting, risk, and innovation at leading financial institutions in North America, Europe, and Latin America, including Citibank and Barclays Group. With a unique global perspective and strategic vision, Ami has been pivotal in shaping Visa's risk strategy.

Katie has broad expertise across Fraud, Authorizations, Claims and Chargeback. With approximately 25 years of experience in the payment card industry, she is proficient in transactional rule optimization, operational workflows, cardholder authentication, and various industry tools pertaining to Fraud and Claims.

She joined Mastercard in 2016 from Bank of America, where she was a Vice President with management and individual contributor responsibilities that included strategies, operations, policy, vendor management, and quality assurance for all card portfolio types and some deposit products. During her time at Bank of America, Katie was instrumental in launching and providing Fraud and Claims management of the Commercial Card programs in EMEA and APAC.

Katie’s responsibilities as a Senior Managing Consultant in Mastercard Data & Services included leading client engagements related to Fraud and Chargeback, intended to provide brand-agnostic guidance and recommendations related to people, processes, systems, and more, based on both quantitative and qualitative analysis. Katie also engaged with merchants and payment facilitators for authorization optimization, custom rule design, and fraud prevention guidance.

Katie went on to lead the Issuer Segment of Mastercard Cyber & Intelligence’s Global Segment Intelligence and Engagement. Her experience of issuer pain points and vast knowledge of Security Solutions allowed her to derive data-driven insights about client opportunities within authorization, authentication, fraud, and loss recoveries.

She now leads a team within Solutions Engineering focused on working with internal Core teams to integrate Security Solutions within consumer products to address customer pain points and enhance the value proposition of the card products.

Chen has been with Justt for over almost 2 years and currently serves as an Enterprise Customer Success Manager at Justt. With two years of dedicated experience in the fintech sector, Chen has developed deep expertise in helping enterprise clients navigate the complex landscape of payment disputes and chargeback prevention. In her role at Justt, Chen works closely with large-scale businesses to optimize their chargeback management strategies, reduce revenue loss, and improve customer payment experiences.

Her hands-on experience with enterprise-level fintech solutions and passion for customer success make her a valuable voice in discussions about payment processing challenges, dispute resolution, and the evolving fintech ecosystem.