Senior Software EngineerSt. Gallen, Switzerland · @xeinebiu

Arzan
Nebiu.

I build polished web and mobile products from idea to launch.

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01 / About
Arzan Nebiu

About me

I turn messy product problems into polished, reliable software people actually use. My deepest strength is mobile and frontend product architecture: shaping workflows, design systems, state/data layers, performance, and release quality. I also work comfortably across backend modernization when the product needs it, especially around APIs, caching, concurrency issues, and database bottlenecks.

By the numbers

0+

years building products

0+

projects shipped

0

owned products

0

original public repos

02 / Work

Experience

Aug 2024 - Present

St. Gallen, Switzerland

Kaspar&

Senior Software Engineer

  • ›Help shape the Kaspar& and Liberty app experience from product requirements through mobile and web implementation
  • ›Drive a full app redesign focused on stability, usability, visual consistency, and stronger confidence with bank partners
  • ›Build and maintain the design system that now powers the full app experience: components, themes, motion, and interaction patterns
  • ›Rebuild the data layer around query-based caching, generated OpenAPI clients, and automatic refresh as Sentry crash-free users improved from 75% to 93%
  • ›Cut slow startup work by moving from 20+ sequential app-loading calls toward backend-owned state and demand-driven loading
  • ›Tune the product for smoother interactions with minimal frame drops on 120Hz devices, including scrolling, transitions, frost effects, and theme toggles
  • ›Make the apps work naturally in German, Italian, French, and English with responsive layouts that respect text scaling and zoom

Aug 2022 - Aug 2024

St. Gallen, Switzerland

ServiceOcean

Lead Engineer

  • ›Led a team of four through delivery planning, hiring, performance feedback, stakeholder communication, code reviews, shipping features, and mentoring
  • ›Diagnosed a production voice server handling roughly 10K peak-hour call requests that stalled around 100-120 concurrent requests while CPU stayed under 10%
  • ›Removed shared request bottlenecks by isolating per-request state, letting the .NET backend use CPU capacity again and respond without thread starvation
  • ›Tracked down random server crashes to an Entity Framework exception being sent to Sentry with circular references, causing recursive serialization and runaway memory usage
  • ›Modernized the product architecture by splitting a monolith into clearer voice, AI, and frontend domains with tenant-specific features across teams and customers
  • ›Moved the frontend from Razor pages to React, using modular boundaries and micro-frontend ideas where tenants needed different capabilities
  • ›Made key workflows noticeably faster by rewriting Entity Framework queries that caused excessive database round-trips
  • ›Worked across C# / .NET Core, React, TypeScript, MSSQL, and Entity Framework to keep delivery moving end to end

Oct 2021 - Jul 2022

Berlin, Germany

Sablono

Senior Software Engineer

  • ›Drove the migration of the web app from AngularJS to modern Angular and TypeScript
  • ›Ran it incrementally as micro-frontends, embedding new Angular code inside the existing AngularJS shell so both frameworks ran side by side during the migration
  • ›Migrated the jobsite mobile app off legacy NativeScript to Flutter, keeping it offline-first for large stadium and hotel projects with thousands of field workers
  • ›Helped preserve progress locally and sync it back online once connectivity returned, reducing the risk of lost field updates
  • ›Worked across AngularJS, Angular, TypeScript, NativeScript, Flutter and Dart, and native Android with Kotlin

Jan 2021 - Aug 2022

Remote

Upwork

Freelancer (Android/Web)

  • ›Scoped product needs directly with clients, translated vague ideas into buildable plans, and shipped Android and cross-platform apps end to end
  • ›Built product prototypes and production apps including an on-device machine-learning translator, embedded Android server, and virtual-space app
  • ›Delivered web and desktop tools such as a keyword analytics platform and a multi-account Google Photos manager in Electron
  • ›Used my own open-source Android libraries to add media playback, streaming, and audio effects faster and with less risk
  • ›Rescued legacy apps by fixing platform deprecations, improving stability, and bringing them back in line with Play Store requirements

Feb 2021 - Sep 2021

Berlin, Germany

Check24

Senior Android Developer

  • ›Built features for Check24's Consumer and Service Provider Android apps, part of Germany's largest comparison platform
  • ›Helped migrate the app from Java to Kotlin, modernizing it with Coroutines, Flows, Room, ViewModels, and Dagger
  • ›Mentored four junior Android developers through feature work, Kotlin adoption, and modern Android architecture patterns
  • ›Modularized the build with custom Gradle scripts to speed up development
  • ›Used Coroutines to untangle and fix concurrency issues

Jan 2018 - Feb 2021

Berlin, Germany

Escriba AG

Full Stack Developer

  • ›Built ESCRIBA's enterprise document-automation product as a full-stack engineer, in Java on the backend and Angular with TypeScript on the front end
  • ›Developed up to nine micro-apps within the product, unifying them with a shared design system and reusable component library
  • ›Worked across the stack against REST APIs, shipping features end to end
  • ›Contributed to architecture and design decisions across three years of Agile delivery
  • ›Helped establish ESCRIBA's branch office in North Macedonia, taking part in hiring and standing up the new team

Jan 2015 - Apr 2019

Tetovo, Macedonia

Turbosoft

Full Stack Developer

  • ›Built web and mobile applications using .NET, AngularJS, and Ionic
  • ›Delivered quiz, warehouse, and appointment systems
  • ›Designed data models and implemented efficient API communication between frontend and backend layers
03 / Products

Selected work

Product case studies with the problem, audience, architecture, and build role made explicit, with numbers included where I can stand behind them.

DJENETE
Shipped product

DJENETE

A wedding planning SaaS that brings guest management, budgets, vendors, timelines, RSVP, seating, and invitations into one coordinated workflow.

Problem
Wedding planning quickly spreads across chats, spreadsheets, vendor notes, budget lists, and guest updates.
Audience
Couples planning a wedding together, with workflows that also account for vendors and family input.
Outcome
A structured planning system that reduces context switching and keeps the couple's core decisions in one place.
Architecture
Next.js website, Vite/React frontend, and NestJS backend with typed planning workflows, collaboration, invitation management, and Stripe payments/subscriptions.
Build role
Defined the product concept, mapped the core workflows, and built the SaaS experience end to end.
Next.jsViteReactNestJSTypeScriptStripe
Gallerif
Shipped product

Gallerif

A secure photo sharing platform for photographers who need private client galleries, password protection, white-label branding, and client-side decryption.

Problem
Photographers need to deliver private client galleries without losing brand control or exposing sensitive shoots.
Audience
Professional photographers working with wedding, commercial, school, and private client galleries.
Outcome
Encrypted, password-protected, white-label galleries with fast delivery and client-side decryption.
Architecture
Next.js website, React frontend, and NestJS backend with AES-256 encryption, CDN-backed delivery, Stripe payments/subscriptions, and a zero-knowledge client-decryption flow.
Build role
Defined the secure sharing workflow, built the product experience, and balanced trust, branding, and delivery speed.
Next.jsReactNestJSTypeScriptAES-256CDNStripe
AN Player
Shipped product

AN Player

A native Android streaming player built around plugins, media playback quality, offline support, and a maintainable Kotlin architecture.

Problem
Media apps often lock users into fixed sources and brittle playback flows.
Audience
Android users who want flexible music and video playback without being tied to one fixed content source.
Outcome
A long-running app with 60K+ downloads, 400-500 monthly active users, a 4.1 rating, extensible sources, stable playback, streaming, and offline support.
Architecture
Native Kotlin app using MVVM, Coroutines, Hilt, ExoPlayer, Firebase, and a plugin-based source layer.
Build role
Owned the product over multiple years, from architecture and playback quality to UX details and release maintenance.
KotlinCoroutinesMVVMExoPlayerHiltFirebase
Zoraxy Analytics Dashboard
Shipped product

Zoraxy Analytics Dashboard

A local-first analytics dashboard for Zoraxy reverse proxy logs, focused on operational visibility without sending logs to a third-party service.

Problem
Reverse proxy logs contain useful operational signals, but teams often need external analytics tools to read them clearly.
Audience
Sysadmins, developers, security teams, and DevOps/SRE engineers running Zoraxy.
Outcome
Local-first analytics with overview metrics, log exploration, IP, host, and file analysis without sending data away.
Architecture
React and TypeScript dashboard with local log parsing, tabbed analysis views, filtering, and Recharts visualizations.
Build role
Designed the information architecture, built the interactive dashboards, and kept the privacy model local by default.
ReactTypeScriptRechartsTailwindZoraxy
04 / Open Source

Original tools I maintain

Non-fork repositories and libraries extracted from real engineering problems, useful as a signal of initiative, API design, and long-term maintenance rather than broad industry adoption.

Featured libraryDart

Dependy

A simple dependency injection library for Dart that simplifies app architecture and testing.

Visit dependy.xeinebiu.com →
All repositories on GitHub →
05 / Skills

Capabilities

Languages

TypeScript · JavaScript · Kotlin · Java · Dart · C# · SQL

Frameworks

Flutter · React · Next.js · Angular · AngularJS · jQuery · Node.js · NestJS · .NET · Ionic · NativeScript · Electron · Tailwind · Recharts

Technologies

Android SDK · Coroutines · Flows · Hilt · Dagger · Room · Retrofit · ViewModels · ExoPlayer · ML Kit · Firebase · Entity Framework · Prisma · PostgreSQL · MSSQL · Redis · OpenAPI

Tools

Git · Docker · Gradle · Webpack · Android Studio · VS Code · Postman · Figma

Spoken

Albanian (Native) · English (Fluent) · German (B1) · Macedonian (B1)

06 / Contact

Let's build something.

Always open to interesting problems and good teams. Drop me a line and I'll get back to you.

[email protected]
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