Jaka Fefer
Open to workLjubljana, Slovenija, CET (UTC+1)
Founding Product Designer for early-stage fintech and AI products.
I design it, ship it as production code, and iterate on real usage.
Recent teams and products
Bonfires
EasyXBluerock
OtarisDeSciWorld
MightyWorks
Faculty Group
Measured results from shipped work
- onboarding completionEasyX
- 40%
- faster handoffDeSciWorld
- 30%
- lower operating costsDeSciWorld
- 27%
- outsourced dev cost cutFaculty Group
- 50%
Selected work
Each study starts with the result and the real screens. The decisions behind them come after.

Bonfires
Sep 2024 - Feb 2026AI agents for communities, Founding Product Designer
About 30% faster frontend implementation
Bonfires had a bot prototype, no interface and no defined users, so I designed the first product UI and the design system, and frontend implementation time dropped about 30%.
Read the case study, 2 min

EasyX
Jan 2022 - May 2024Crypto derivatives trading, Founding Product Designer
Onboarding completion up about 40%
Beginner traders were quitting after costly early mistakes, so I designed education-first onboarding and a practice sandbox, and onboarding completion rose about 40%.
Read the case study, 2 min

Bluerock
Client projectCrypto index investing, Founding Product Designer
Complete UI and design system, did not launch
Crypto index investing was too complex to explain with trading-terminal UI, so I designed it around weights, rule-based rebalancing and growth projections and delivered a complete UI and design system before the product stalled on funding.
Read the case study, 2 min

Otaris
2021 - 2022Early-stage deal platform, Founding Product Designer
Full investor platform, company pivoted before launch
Investors had no way into curated early-stage deals and no way to sell vested allocations, so I designed the whole investor platform, from onboarding to a marketplace for partial allocations, and it was fully designed when the company pivoted before launch.
Read the case study, 2 min
How I work
One person from the first sketch to the shipped screen, so less gets lost between design and build.
- Step 1
Design with the people who use it
Interviews, flows and prototypes in Figma, tested with real users before anything is built. On EasyX that meant 50+ participants before launch.
- Step 2
Ship it as production code
I build the product UI, landing pages and design system components myself with Claude Code and Cursor, so what ships matches what was designed.
- Step 3
Measure and iterate
Usage data in PostHog shows what people actually do with it, and the next iteration starts from that.
Both versions of this portfolio were built this way, from a written plan, one pull request at a time. How the Figma-style version is built
Experience
Fintech, DeFi and early-stage products, mostly as the first designer on the team.
Download the full CV (PDF)DeSciWorld
Nov 2024 - Aug 2025Product Designer & Manager, remote
- Owned product design and UX for a research and collaboration platform, contributing directly to product direction and roadmap decisions.
- Designed and maintained a design system in Figma using variable tokens for typography, color, spacing, and theming, supporting long-term consistency and faster development.
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- Built responsive UI frameworks using auto-layout, component logic, and prototyping techniques, reducing design-to-development handoff time by 30%+.
- Created production-aligned, testable prototypes that accelerated iteration cycles and improved alignment between design and engineering.
- Worked closely with engineers throughout implementation, resolving layout and UI issues directly and improving accuracy between design intent and shipped product.
- Led UX reviews and flow optimizations, improving usability and consistency across core user flows.
- Partnered with the founder on product and operational cost decisions, identifying inefficiencies that reduced monthly operating costs by ~27% and extended the company's runway.
MightyWorks
Nov 2024 - Dec 2025Co-Founder, Product Designer, remote
- Co-founded a product and design studio delivering branding, UX, and product design for 20+ client projects across fintech, infrastructure, and data-heavy products.
- Led discovery workshops and design sprints, translating ambiguous client needs into clear product direction, priorities, and roadmaps.
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- Designed multiple zero-to-one products, creating modular design systems and responsive UI patterns optimized for efficient development.
- Managed up to five parallel client engagements, coordinating scope, timelines, and client communication.
- Conducted usability interviews and post-launch iteration cycles to validate assumptions and continuously improve shipped products.
- Balanced client expectations, scope, and delivery timelines across multiple concurrent engagements, ensuring sustainable execution in a services-based business.

EasyX
Jan 2022 - May 2024Product Designer, remote
- Designed UX for an early-stage, high-risk trading platform where users made irreversible financial decisions, requiring strong confirmation, error prevention, and trust signals.
- Led the design of structured onboarding and critical decision flows, improving onboarding completion by ~40% while reducing user errors through clear risk communication and confirmation patterns.
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- Built and tested interactive prototypes with 50+ participants, translating usability findings into concrete improvements before launch.
- Collaborated with product leadership on feature tradeoffs, scope reduction, and prioritization based on user needs, competitive analysis, and engineering constraints.
- Was the final design gate for high-risk user flows, blocking unsafe or unclear interactions from shipping and enforcing simplified, lower-risk solutions under time and delivery constraints.
Otaris
Jan 2021 - Nov 2022Product Designer, Scrum Master, remote
- Joined the founding team as its first product designer, defining core UX flows and UI systems from the ground up.
- Took on the Scrum Master role, coordinating sprint planning, backlog grooming, and team rituals across design and engineering.
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- Led a product and engineering team to deliver a polished, production-ready product under startup constraints.

Faculty Group
Jan 2019 - Oct 2022Product Designer, Project Manager, remote
- Designed UX and UI for multiple digital products, turning user feedback into actionable design iterations.
- Managed design and delivery across four concurrent projects, maintaining consistency and execution quality.
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- Identified inefficiencies in an outsourced development engagement, resulting in a 50% cost reduction over six months.
Earlier and shorter roles
- Social Kung Fu, Product DesignerMay 2023 - Dec 2023
- X8C Marketing Agency, Graphic DesignerJul 2019 - Nov 2021
Skills and education
Design
- Product Design (UI/UX)
- UX Research
- User Journey Mapping
- Interaction Design
- Design Systems
- Prototyping & Validation
- Risk-aware UX & Trust Design
- Data-dense Interface Design
Product and delivery
- SCRUM
- Project Management
- Product Discovery & Prioritization
Technical
- AI-assisted prototyping
- Code-adjacent design workflows
- Design-Engineering Collaboration
- Design-adjacent frontend implementation
Education
Graphic and Media Technology
Faculty of Natural Sciences and Engineering
2016 - 2019
UX Design Professional
Google
Jul 2021 - Dec 2022
Responsive Web Design Developer
freeCodeCamp
Mar 2020
Tools
- FigmaUI Design, prototyping
- Adobe Creative SuiteDesign
- CursorPrototyping
- ClickUpProject Management
Languages
- SlovenianNative
- EnglishProfessional working
- SpanishElementary
About
Founding Product Designer, 7+ years in fintech, DeFi and early-stage products where users make irreversible decisions. I build what I design. Product UI, landing pages and design systems shipped as production code with Claude Code and Cursor, tested against real usage in PostHog.
I've been the first designer at several companies, owned the design system, the onboarding and the risk flows, and sat with founders on scope and cost decisions.
Outside work I play drums, ride downhill mountain bike trails, practise card magic and make Neapolitan pizza for friends.
Hiring a product designer?
I am open to work, based in Ljubljana and used to working remotely across time zones. Email is the fastest way to reach me.
fefer.jaka@gmail.com