Marc J Sandifer

Product Lead

Berlin, Germany

German (native)
English (native)
Python (learning)


Training and CoachingProduct StrategyTeam Building

Servant Leadership

Agile Processes

Cross-Functional Collaboration

Scrum Product Ownership

CRO & Testing

Data-Driven UX


Jun. ’21 – current, Contorion GmbH, Berlin



Team Lead Product Management

Establishing and leading Contorion’s E-Commerce Experience product area, currently consisting of 5 cross-functional product development teams with 6 Product Managers and an EDI (merchant integration) manager.

• Ensuring product teams’ alignment with the company strategy
• Setting product teams’ and pillar’s vision and strategy through a bottom-up approach
• Hiring, coaching, mentoring, and developing empowered Product Managers in charge of customer experience, payment, logistics, and product data, as well as Contorion’s product innovation efforts
• Introducing, facilitating and iteratively improving cross-departmental discovery, testing, and delivery processes
• Holding PM workshops and trainings on product management, strategy and various adjacent topics, e.g. web analytics, business model analysis, horizontal leadership and Ikigai

Key Skills:
Servant Leadership · Product Strategy · Coaching & Mentoring · Cross-Functional Collaboration · Team Building

Nov. ’19 – May ’21, Contorion GmbH, Berlin



Senior Product Manager

In addition to the responsibilities and skills listed under “Product Manager”:

• Owning Contorion’s frontend, UX, and testing strategy
• Onboarding and mentoring all Product Managers in the areas Conversion Rate Optimization, web analysis and marketing, as well as Contorion’s systems and processes
• Onboarding, mentorship and supervision of a Product Management Trainee
• Training & mentorship of a Junior Product Manager

Key Skills:
Cross-functional Team Leadership · Employee Training · Mentoring · Conversion Rate Optimization · Product Strategy

Editorial: “Improving an Online Shop” (German)

Mar. ’18 – Oct. ’19, Contorion GmbH, Berlin



Product Manager

Shaping Contorion’s customer experience as the Product Owner of an 8-12 person SCRUM team, as well as driving Contorion’s experimentation efforts.

• Continuous data-driven feature design and implementation
• Establishing a testing and data-driven UX culture within the organization
• Creating and maintaining the team’s development roadmap
• Onboarding and mentoring all Product Managers in conversion rate optimization, testing, and data-driven UX
• Identifying and solving major UX blockers, significantly improving key metrics across the funnel
• Leading stakeholder CRO teams
• Analysis and tracking of all relevant KPIs
• Implementation and maintenance of web analysis tools

Key Skills:
Cross-functional Team Leadership · Product Development · Usability Testing · Data-driven Decision Making · Conversion Rate Optimization

Oct. ’13 – Feb. ’18, Nexon Europe GmbH, Berlin



(Lead) Product Manager

Leading a team in charge of Product Management and Operations for ‘Combat Arms’, Nexon Europe’s highest grossing product.
Supporting Business Development and Product Sourcing

• Hiring, training and mentoring Product Management and Operations staff
• Owning all aspects of the product, from the development roadmap to publishing and monetization strategy
• Product sourcing and market research
• Supervising and coordinating Database Administration, Operations Engineering, Quality Assurance, Customer Support and Community Management

Product Management & Operations · Product Launch · Data-driven Decision Making · Mentoring · Cross-functional Team Leadership

Combat Arms Interview: UI/UX Update