Mariusz Cieśla - Resume
Principal Product Designer based in Berlin, Germany
Contact: Email: work@mariusz.cc | Location: Berlin, Germany
About
Product design leader and design engineer with almost two decades of experience. I specialize in design systems, user experience research, and collaborative design processes. I've worked with product teams, agencies, and consulted for large corporates, always focusing on continuous improvement and purpose-driven design.
Work Experience
Principal Product Designer - LILT (2025 - Present)
Focused on exploring AI tooling capabilities and building user-centered design solutions that bridge human creativity with AI efficiency. Leading strategic design initiatives to enhance product experiences through innovative AI-powered workflows.
- Exploring and implementing cutting-edge AI tools to enhance design workflows and product development velocity
- Building intuitive design solutions that prioritize user needs while leveraging AI capabilities for enhanced experiences
- Creating scalable design systems and processes that maximize impact while minimizing complexity
- Leading product design strategy with focus on AI integration and human-centered innovation
- Working closely with engineering and product teams to deliver cohesive AI-enhanced user experiences
Key skills: AI Tooling, Product Strategy, Design Systems, User Experience, Innovation, Strategic Design
Senior Manager, Product & Design - LILT (Apr 2024 - 2025)
Led cross-functional Product & Design teams to accelerate delivery, adoption, and customer impact for the AI-powered translation platform.
- Led cross-functional Product & Design teams to accelerate delivery, adoption, and customer impact
- Owned brand, visual identity, and Design System, ensuring global consistency and market differentiation
- Streamlined internal & partner collaboration, cutting project turnaround times while elevating quality
- Designed and shipped high-impact prototypes enabling rapid iteration and early market validation
- Directed user research to inform strategic product decisions and boost retention
- Pioneered AI-driven design workflows (Cursor, Figma MCP), increasing design velocity and reducing engineering bottlenecks
Key skills: Design Management, Team Leadership, Design Systems, AI Workflows, User Research, Brand Strategy
Senior Product Designer - LILT (2020 - 2024)
Led design initiatives across multiple product areas for the AI-powered translation platform.
- Built cross-functional design system (Figma + Storybook + docs) that aligned teams and reduced UI-related issues to near-zero
- Designed complex workflows that simplified project lifecycles without sacrificing power for expert users
- Led design for AI-powered translation agent, focusing on trust, transparency, and collaborative human-AI workflows
- Collaborated on product roadmap and user research initiatives across multiple product areas
Key skills: Design Systems, AI/ML Product Design, Workflow Design, User Research, Accessibility
Product Designer & Consultant - Freelance & Agencies (2013 - 2020)
Worked with various product teams, agencies, and consulted for large corporates across different industries.
- Delivered design solutions for fintech, e-commerce, media, and enterprise software
- Partnered with design agencies on large-scale digital transformation projects
- Provided UX strategy and design system guidance for enterprise clients
- Embedded with product teams to improve design processes and collaboration
Key skills: UX Strategy, Digital Transformation, Enterprise Design, Process Optimization
Head of Design - anynines (2014 - 2020)
Created and maintained coherent style guides and design systems across different teams, while collaborating with Marketing on growth initiatives and experimentation frameworks.
- Created and maintained coherent style guides and design systems across multiple product teams
- Ensured design consistency and standards across different departments and initiatives
- Worked closely with Marketing team on new growth initiatives and strategic experiments
- Developed and implemented systematic approaches to testing and iterating on growth strategies
Key skills: Design Leadership, Developer Experience, Enterprise Design, Cloud Platforms, Design Systems
Co-founder & Product Designer - Lifetramp (2014 - 2018)
Co-founded and led product design for a mentorship marketplace that let people "test-drive" careers for a day.
- From hypothesis to launch, scaling to 10K+ users, and eventual wind-down
- Designed and ran concierge MVP, monetization models, and internationalization efforts
- Created complete brand identity, user experience, and front-end development
- Collaborated on 2-season TV documentary series with Planete+ showcasing user journeys
- Achieved global press coverage (Forbes, Fast Company) and expansion to multiple countries
Key skills: Product Strategy, Brand Identity, Growth Experiments, Community Building, Prototyping
Visiting Lecturer - AGH University of Science and Technology (2016 - 2020)
Delivered lectures and workshops on visual design, sharing practical experience with the next generation of designers.
- Developed and delivered courses on visual design and digital product development
- Integrated real-world case studies and hands-on projects into academic curriculum
- Connected academic learning with current industry practices and trends
- Guided students through design projects and career development
Key skills: Education, Curriculum Development, Mentoring, Visual Design, Workshop Facilitation
Lead Designer (Contract) - LILT (2015 - 2017)
Built the original design system for LILT and collaborated with engineering and stakeholders on new initiatives for translators.
- Created the original design system that laid the groundwork for future product evolution
- Designed interfaces specifically for translators, who were the primary users at the time
- Worked closely with engineering and stakeholders to deliver new product initiatives
- Helped shape the product direction during critical early growth phase
Key skills: Design Systems, User-Centered Design, Cross-functional Collaboration, Early-Stage Product
Lead Designer & Front-end Developer - Kanbanery (2009 - 2013)
Designed and developed the interface for an online kanban board platform, working directly with users and internal stakeholders.
- Owned both interface design and front-end code implementation
- Worked directly with users to understand their workflow needs and pain points
- Led design decisions and interface development for the entire platform
- Collaborated with internal stakeholders to align product vision with user needs
Key skills: Product Design, Front-end Development, User Research, Interface Design, Kanban/Agile
Front-end Developer & Designer - Lunar Logic (2008 - 2013)
Designed and developed user interfaces for web applications using Ruby on Rails, HTML, CSS, Sass and JavaScript.
- Designed and implemented user interfaces from concept to production
- Worked extensively with Ruby on Rails applications and MVC architecture
- Utilized Sass and modern CSS techniques for maintainable stylesheets
- Worked directly with clients to translate requirements into functional interfaces
Key skills: Ruby on Rails, HTML/CSS, Sass, JavaScript, Interface Design
Front-end Developer - Making Waves (now NoA Ignite) (2007 - 2008)
Worked with enterprise and government customers in Norway on custom application development using .NET framework and web technologies.
- Developed custom applications for large enterprise and government clients
- Worked with Microsoft .NET framework for web application development
- Implemented user interfaces using HTML, CSS and JavaScript
- Gained valuable experience working in the Norwegian market
Key skills: .NET Framework, HTML/CSS, JavaScript, Enterprise Applications, Government Projects
Core Skills
Design & Strategy
- Product Design
- Design Systems
- User Research
- Product Strategy
- Information Architecture
Collaboration
- Cross-functional Teams
- Agile/Shape Up
- Design Sprints
- Stakeholder Management
- Mentoring
Technical
- Figma
- Prototyping
- HTML/CSS
- Accessibility
- Analytics
- AI Tooling: Claude Code, Gemini CLI, Cursor, Lovable
Design Principles
Kaizen
Using Japanese philosophy of continuous improvement through small, incremental changes to continuously improve processes and workflows.
Purpose
Learning to understand 'why' behind every decision. Great design solves real problems and creates meaningful experiences for users.
Collaboration
The best learning happens together. I value feedback, diverse perspectives, and the collective wisdom of teams working toward common goals.
Iteration
First draft is rarely best outcome. I use user data and business goals to ensure the final product actually performs.
Languages
- English - Fluent
- Polish - Native
- German - Conversational