BEHIND STAYUX
Profile
STAYU KASABOV
Your idea. Prototyped fast. Built with confidence.
I design and build working prototypes for founders, domain experts, entrepreneurs, and product teams. Then I validate them with tests, heuristics, and metrics before you commit to a full build.
What I do:
Product prototyping and validation. From SWOT and UX research to design, a working prototype, and an MVP. Built with AI using Claude Code, context engineering, and spec-driven development.
UX and accessibility audits. Heuristic reviews, conversion funnels, A/B tests, Core Web Vitals, search visibility, and WCAG 2.2. You get prioritized fixes in a clear order.
Brand design and market differentiation. Positioning, market research, continuous discovery, and customer experience. Design systems in Figma when the product needs one.
Design first, build second. You can start at any stage, from a raw idea to a live product. A network of trusted professionals takes your product past the MVP into deployment, security, and scale.
Send me a collection of requirements, business logic, or a broad idea. I reply within 24 hours.
Value
WHY WORK WITH ME
WHAT I BRING
Lead the transition from initial research to final execution. Define the logic behind the interface through user flows, heuristics, and technical vetting. Ensure the product is built on a foundation that is both user-centric, business aligned and technically viable and accessible to WCAG standards.
Focus on the 'how' as much as the 'what'. My expertise lies in creating seamless handoffs through precise documentation and an in-depth understanding of implementation constraints. Ensure that the design intent remains intact throughout the development cycle.
I use prototyping as a tool for validation, with a systemic approach to solve complex problems. Helping teams move from MVP to a scalable product without losing functional integrity.
Maintain a critical approach to new technology, adopting new workflows and tools only when they enhance production speed or product quality.
Services
WHAT THE ENGAGEMENT COVERS
STRATEGY
Product Direction
Clarifying what the product is, who it is for, and whether the answer is honest.
Product-Market Fit
Testing whether the problem being solved is real, urgent, and worth solving at all.
Business Alignment
Connecting product decisions to what the business actually needs to achieve.
RESEARCH + DESIGN
User Research
Finding out what real users do, need, and struggle with - not what they say they want.
UX Design
Flows, wireframes, and interaction logic - how the product behaves from the user's perspective.
Design System
A coherent component library that makes every future design decision faster and more consistent.
ARCHITECTURE +
Architecture
Defining the structural logic - what the product is made of and what comes in which order.
PRD Authoring
Writing requirements that define scope, constraints, and success before building begins.
Design Oversight
Senior judgment for teams with designers but no voice asking if the right problems are being solved.
Capabilities
CAPABILITY SET
Stack
TECH STACK
History
TRACK RECORD
2022 — Present
Product Design | AI prototyping and product idea validation
Stayux.com
Your idea. Prototyped fast. Built with confidence.
I design and build working prototypes for founders, domain experts, entrepreneurs, and product teams. Then I validate them with tests, heuristics, and metrics before you commit to a full build.
11+ client organizations in SaaS, media, and e-commerce, under NDA. I work closely with product managers and engineers.
What I do:
Product prototyping and validation. From SWOT and UX research to design, a working prototype, and an MVP. Built with AI using Claude Code, context engineering, and spec-driven development.
UX and accessibility audits. Heuristic reviews, conversion funnels, A/B tests, Core Web Vitals, search visibility, and WCAG 2.2. You get prioritized fixes in a clear order.
Brand design and market differentiation. Positioning, market research, continuous discovery, and customer experience. Design systems in Figma when the product needs one.
Design first, build second. You can start at any stage, from a raw idea to a live product. A network of trusted professionals takes your product past the MVP into deployment, security, and scale.
2005 — 2022
Chief Executive Officer & Founder
Nuvizus Communications · Full-time
Founded and ran a digital product agency.
Led product strategy, UX and delivery for 50+ clients in technology, media and entertainment, with a rotating team of 5 designers and 15 developers.
Planetaplay.com (CPO and product owner). Bulgaria's first VOD/OTT platform built into a TV production pipeline. Owned strategy, SWOT, PRD, UX research, brand and technology direction. Grew to 500,000+ registered users and 4.8M shared playlists. A mobile operator acquired the user base and technology.
10-year engagement with Payner Ltd / Planeta TV - the biggest Bulgarian record label and production company (2006 to 2016). Designed, grew and managed full product family. Planetaplay (VOD), Planetapartner (IPTV integration and embed control API), Planetaface (unified identity across sites), Paynerstore (merchandise) and an event system on Payner.bg.
Designed and led the development of a proprietary CMS (2003) with role-based access, granular permissions and content workflows. Deployed for ING Bank (Perperikon.bg), TV7 and Planeta.tv.
Won the design contest for the b-trust.org e-signature portal (Borica-Bankservice) in 2005, which introduced UX design methodology to the Bulgarian market.
Designed, built and shipped MVPs and web products on ExpressionEngine.
Managed client relationships across long engagements, hired the teams and managed the designers and developers.