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Available for select projects

I build products end to end: web, mobile, and the systems behind them.

I'm Duart Nishefci, a software engineer from Kosovo. I've built Web3 funding flows, health-data integrations, App Store apps and an eSIM business I co-founded, usually owning the work from architecture to release.

See selected workGet in touch
Based in
Kosovo
Local time
Works across
Web, mobile, APIs
system.mapwhat I build
WebNext.js, ReactMobileReact Native, ExpoServicesNode.js, GraphQLIntegrationsAuth, KYC, EMRDataSupabase, FirebaseDeliveryAWS, Cypress
/work4 products

Selected work

Products I've built or helped build: what each one does, the problem behind it, and the parts I owned.

app.thrive.xyz

Thrive

Crypto's GDP layer

A funding platform that attracts top builders and pays them when they create value, so ecosystem funds are allocated with 100% capital efficiency.

Problem
Ecosystem funds are hard to allocate well. Thrive ties funding to value that builders actually create, instead of paying for promises.
Role
Frontend Engineer

What I built

  • Wallet and social login with Dynamic.xyz, plus the migration of existing users and wallets across Hedera, Xion and Ethereum
  • KYC verification with Sumsub, built into onboarding
  • A shared adapter layer so several apps consume one unified data source
  • SEO, accessibility and performance work: code splitting, lazy loading, better FCP and CLS
  • Storybook documentation and a more reliable Cypress pipeline

Stack

  • Next.js
  • React
  • TypeScript
  • Tailwind CSS
  • AWS
Visit app.thrive.xyz(opens in a new tab)

blue-esim.com

Blue eSIM

eSIMs for travelers

An online service where travelers buy and manage eSIMs for their trips, without hunting for a local SIM card when they land.

Problem
Staying connected abroad usually means roaming fees or swapping physical SIMs. Blue eSIM moves the whole thing online.
Role
Co-founder, frontend lead

What I built

  • Led the frontend design and development of the customer experience
  • A responsive interface for browsing plans, buying, topping up and checking balance
  • Backend contributions and the integration between both sides of the platform
  • Pricing strategy and market analysis on the business side

Stack

  • Next.js
  • TypeScript
  • Tailwind CSS
  • Supabase
Visit blue-esim.com(opens in a new tab)

paiwe.tech

PAIWE

A portfolio for real-world assets

A mobile app that tracks the real resale value of high-end pieces, so every watch, sneaker or gold coin someone owns can be followed like an investment.

iOS app4 screens
Four PAIWE app screens: onboarding, portfolio overview with value history, adding an asset, and an asset detail page
Problem
Collectors know what they paid, but rarely what their pieces are worth today. PAIWE tracks resale value over time, like a portfolio.
Role
Frontend Engineer, mobile lead

What I built

  • The React Native app from scratch: project structure, reusable components and state management
  • Ownership of the client-side architecture and delivery of every feature
  • Integration with the Golang microservices backend
  • Releases and deployments to the Apple App Store

Stack

  • React Native
  • TypeScript
  • Expo
  • AWS
Visit paiwe.tech(opens in a new tab)

Mobile app

Airpop

Social app for the people around you

A social app for connecting with people nearby and sharing moments with the world through quick photo pops.

Mobile app4 screens
Four Airpop app screens: nearby people discovery, chat list, a received photo pop, and a user profile
Problem
Most social feeds revolve around people you already know. Airpop puts the people around you front and center.
Role
Software Engineer

What I built

  • Features across both the front end and the back end of the app
  • Real-time features on Firebase, built with performance in mind

Stack

  • React Native
  • TypeScript
  • Firebase

Mobile app, no public web link

/aboutKosovo, CET

More than the frontend.

My background is frontend-heavy, but the work rarely stops there. Here's where it has reached, and where I did it.

I'm a software engineer from Kosovo. I like taking an idea that's still fuzzy, turning it into something people can actually use, and then doing the less glamorous work that keeps it running.

Along the way I've co-founded a company, led a mobile app from an empty repo to the App Store, and helped move a legacy platform onto a modern stack without a big-bang rewrite.

Working with me

  • Open, frequent communication with the people I build for
  • Flexible across time zones
  • Comfortable in large, distributed teams

Where my work reaches

Frontend

Designed a React, Nx and RTK Query architecture to replace a legacy Razor app, migrating it feature by feature.

Ritech

Mobile

Built PAIWE's React Native app from scratch and took it through App Store release.

PAIWE

Backend & APIs

Built a Playwright PDF-generation service and an EMR sync that keeps patient data aligned with external systems.

91Life

Integrations

Wallet and social auth, Sumsub KYC, and a user and wallet migration across Hedera, Xion and Ethereum.

Thrive

Delivery

App Store releases, AWS-backed products, and steadier Cypress pipelines for consistent deployments.

PAIWE, Thrive

Product

Co-founded Blue eSIM: built the product, then worked on its pricing and market analysis.

Blue Innovations

AI

Claude Code, Cursor and GitHub Copilot in my everyday workflow, and math, programming and reasoning work written for US-based AI labs.

Mercor, daily work

/stackDaily drivers

Tools I reach for.

Grouped by where they sit in a product, with the projects where they showed up. Highlighted ones are my daily drivers, and AI tools are part of how I use all of them.

Frontend

Where most of my hours go

  • TypeScript(daily driver)All four products
  • React(daily driver)Thrive, Ritech
  • Next.js(daily driver)Thrive, Blue eSIM
  • Tailwind CSSThrive, Blue eSIM
  • RTK QueryRitech
  • NxRitech

Mobile

From first screen to store release

  • React Native(daily driver)PAIWE, Starswapp
  • ExpoPAIWE
  • Flutter

Backend & data

Services, APIs and storage

  • Node.js
  • GraphQL
  • Java
  • SupabaseBlue eSIM
  • FirebaseStarswapp
  • Playwright91Life

Quality & delivery

Keeping it shippable

  • CypressThrive
  • StorybookThrive
  • AWSThrive, PAIWE
  • Vercel
ai.workflowEvery change gets a human review

AI in the loop, me in charge.

AI tools are part of my everyday workflow. They help me read unfamiliar code faster, draft the routine parts and test ideas quickly. What ships is still read, tested and owned by me.

I've also worked on the other side: writing math, programming and technical-reasoning work for US-based AI labs through Mercor.

  • Claude CodeAgentic work in the terminal: exploring unfamiliar codebases, multi-file changes and refactors.
  • CursorAn AI-native editor for fast, in-context iteration on the code in front of me.
  • GitHub CopilotInline completions for the routine parts, so attention goes to the hard ones.
  1. Prompt
  2. Generate
  3. Review (human checkpoint)
  4. Test (human checkpoint)
  5. Ship
Human checkpoint

Integrations shipped

  • Dynamic.xyz
  • Sumsub
  • Hedera, Xion & Ethereum wallets
  • Golang microservices
  • EMR systems
/experienceMost recent first

Where I've worked.

7 roles across legal tech, Web3, health tech, mobile, and a company of my own. Open any role for the details.

  1. Ritech International AG

    Frontend Engineer, Legal tech

    Modernizing the CompexLegal platform, from legacy Razor views to a new React architecture, one feature at a time.

    • React
    • Nx
    • Tailwind CSS
    • RTK Query
    • Razor
    • Maintained and improved the existing CompexLegal application, built on legacy technologies such as Razor.
    • Worked on a CSS revamp of the legacy system, improving UI consistency and preparing the codebase for modern technologies.
    • Developed a new frontend architecture with React, Nx, Tailwind and RTK Query to modernize the platform and improve maintainability.
    • Contributed to a gradual migration strategy: rebuilding features in the new React app and integrating them into the legacy system incrementally, for a seamless transition.

  2. Mercor

    STEM Expert, AI labs

    Wrote mathematics, programming and technical-reasoning work for US-based AI labs.

    • Mathematics
    • Programming
    • Technical reasoning
    • Contributed as a writer on multiple projects with US-based AI labs, focused on mathematics, programming and technical reasoning.
    • Collaborated with large distributed teams on projects involving hundreds of participants and domain experts.

  3. Blue Innovations

    Co-Founder, Travel connectivity

    Co-founded Blue eSIM and led its frontend, while working on the backend and the business behind it.

    • Next.js
    • TypeScript
    • Supabase
    • Product
    • Co-founded Blue eSIM, an online platform providing affordable eSIMs for travelers.
    • Led frontend design and development, building a seamless, responsive interface for customers.
    • Contributed to backend development, ensuring smooth integration and functionality across the platform.
    • Shaped the business side too, including market analysis and pricing strategy.

  4. Thrive Protocol

    Frontend Engineer, Web3

    Auth, wallet migration, KYC and frontend quality for a Web3 funding platform.

    • React
    • TypeScript
    • Dynamic.xyz
    • Sumsub
    • Storybook
    • Cypress
    • Implemented a secure authentication system with Dynamic.xyz, streamlining wallet and social logins for a seamless Web3 experience.
    • Led the migration of user accounts and wallets (Hedera, Xion and Ethereum), using Dynamic.xyz webhooks and websockets for a smooth transition.
    • Integrated KYC verification with Sumsub, improving compliance and onboarding.
    • Improved SEO and accessibility with react-helmet-async, aria-labels, meta tags and alt text, and optimized performance through code splitting, lazy loading, and FCP and CLS improvements.
    • Maintained and helped design a shared adapter repository that abstracts backend endpoints, so multiple apps consume a single, unified data source.
    • Added Storybook documentation for React components, improving UI consistency and developer onboarding.
    • Optimized the Cypress testing pipelines, reducing flakiness for more consistent deployments.

  5. PAIWE

    Frontend Engineer, Asset tracking

    Led the React Native app from an empty repo to the App Store.

    • React Native
    • TypeScript
    • Expo
    • App Store
    • Led the frontend engineering of a React Native mobile app, owning architecture, development and delivery of all client-side features.
    • Integrated the app with Golang microservices, keeping communication between client and backend efficient and reliable.
    • Built the application from scratch, establishing a scalable project structure, reusable components and state management.
    • Managed the release process and deployments to the Apple App Store.

  6. 91Life

    Software Engineer, Health tech

    Full-stack features that move data from Holter wearables into EMR systems.

    • Full-stack
    • Playwright
    • EMR integration
    • Developed a dedicated PDF-generation service with Playwright, handling generation workflows efficiently and at scale.
    • Designed and implemented a full-stack solution from scratch that lets users view, analyze and push Holter wearable data to EMR systems.
    • Built a full-stack feature that synchronizes the patient database with external EMR systems, keeping data accurate and in real time.

  7. Starswapp

    Software Engineer, Social and mobile

    Front-end and back-end work on a real-time social app and a car-services platform.

    • React Native
    • Firebase
    • Played a key role in developing a social media app, contributing to both front-end and back-end functionality.
    • Used React Native and Firebase to build a high-performance app with real-time features.
    • Contributed significantly to a car-services management app, keeping service requests efficient to manage.
/approachRuns again for every feature

How I work.

Writing code is only one part of it. This is the pipeline I take work through, from understanding the problem to improving it once it's live.

pipeline: idea to production5 jobs
  1. 1

    Understand

    discover

    What problem are we solving, for whom, and what does success look like? Goals, users and constraints come first.

  2. 2

    Plan

    architect

    Structure, data, key flows and the right stack. A plan we agree on before any code is written.

  3. 3

    Build

    implement

    Small, reviewable pieces, sped up with AI tools and checked by me, with regular updates so nothing is a surprise.

  4. 4

    Iterate

    review

    Real feedback on working software. Test, adjust and tighten the parts that matter most.

  5. 5

    Ship & improve

    deploy

    Release to production, watch how it behaves, and keep improving once it's in people's hands.

/contact

Tell me what you're building

A new product, a legacy migration, or an app that needs to reach the store. If it's worth building, I'm happy to talk it through.

duartnishefci@gmail.com