Berkay Arda YıldızFrontend · Angular & React · 3+ years · İstanbul

I rebuild frontends without freezing the roadmap.

Frontend at Twin Science, where I moved app.twinscience.com from Angular 16 to 22 and took its mobile Lighthouse score from 50 to 94. Before that, six published mobile games as sole developer.

Employed full-time — taking freelance projects alongside it

Selected work Download CV Freelance & contact

Twin Scienceİstanbul, TR

Selected work

01/ 04

Four builds that had to survive real users.

An AI-powered K-12 platform at work, an AI study app I founded, a film platform on web, iOS and Android, and a published library. Each one with the problem, my role and what was measured.

All projects

app.twinscience.com

Twin Science · Angular 16 → 22

2023 —

Problem: An AI-powered K-12 STEM platform for teachers and students, EBA-integrated and in four languages. I inherited it on Angular 16; when I measured it in August 2026, production mobile Lighthouse was 50 with a 12.7 s LCP.
Role: Lead frontend developer since July 2023; 88% of today's code is mine. Built the 33-tool AI content generator, the streaming assistants, and the quiz and smart-board Presentation Mode.
Stack: Angular 16 → 22TypeScript 6SignalsZonelessSSRTiptapVitestPlaywright
Result: 94mobile Perf. (from 50)1.8sLCP (from 12.7)2,191tests (from 0 running)
PageSpeed Insights lab run, Lighthouse 13.5, 16 Oct 2026; desktop 91, Best Practices and SEO 100. ~5,800 commits; tests block pull requests and deploys.

Details app.twinscience.com

demostra.app

Demostra

2026

Problem: Rereading creates an illusion of knowing, and exam apps are built around question banks. None of them ask you to put the source away and explain the topic in your own words.
Role: Founder and sole developer: mobile app, backend and website. GPT-6 Luna grades each explanation, speech is recognised on the device, and weak topics come back on a schedule capped by the exam date.
Stack: React Native (Expo)TypeScriptNode.jsMongoDBGPT-6 LunaElevenLabsRevenueCat
Result: 3weeks to Google Play5weeks to both stores98test files
Counted from the first commit. Live on the App Store and Google Play, with subscriptions since 1.1; newly launched and gaining its first users.

Details Live App Store Google Play

cinekholm.com

Cinekholm

2025 —

Problem: An AI-powered film discovery platform with multi-dimensional taste profiles, recommendations and a social layer.
Role: Full-stack developer and AI engineer.
Stack: React NativeAngular SSRTypeScriptGPT-6 LunaMongoDBRedis + BullMQSocket.IO
Result: 98Desktop Perf.80mobile1.0sLCP
Shipped to web, iOS and Android. PageSpeed Insights, 100 Best Practices, 100 SEO.

Details Live App Store Google Play

npmjs.com/package/bay-carousel-ng

bay-carousel-ng

2026

Problem: The carousel I kept rewriting per project, pulled into one standalone Angular 21 library — breakpoint handling, drag, autoplay and template overrides.
Role: Author and maintainer.
Stack: Angular 21TypeScriptSCSSnpm
Result: ~600npm downloads5modes
Published on npm in March 2026. Its only dependency is tslib — no third-party slider or gesture package.

Details npm GitHub

Speed is not a feature you bolt on at the end. It is product quality, and it is a requirement from the first commit.

Volunteering · YGASince 2024 I have taught science with Twin kits to 600+ children in the earthquake region, and trained teachers on the platform I build.The fields

Freelance

Four kinds of outside work I take on.

Scoped and scheduled around a full-time role, so the timeline is realistic from the first day. I say no to anything I cannot finish properly.

Products from zero: web, mobile, SaaS

From idea to the app stores: the web app, iOS and Android, the backend, subscriptions and the admin panel your team runs it from. I build and ship it end to end on my own, multi-tenant SaaS included.

Cinekholm and Demostra: web, iOS and Android · Tuzluk: multi-tenant SaaS · Twin admin panel: React 19, 70 releases

Per project

Performance audit

I measure a live Angular, React/Next.js or WordPress site and open up its render path, bundles, caching and database queries. You get a prioritised list of fixes, and I can ship them.

app.twinscience.com mobile Lighthouse 50 → 94 · twinscience.com database time 1.75 s → 0.10 s

1–2 weeks

Upgrades and migrations

Bringing an old Angular version up to date — standalone, signals, zoneless, SSR — or rebuilding a legacy app in React, in slices, with releases going out throughout.

Angular 16 → 22 · Angular 10 admin panel → React 19, v1.0 in a month

Scoped per project

AI in your product

Streaming assistants, page context that never exposes user data, and generators whose output people can edit. Features people open every day, not demos.

Twin: a 33-tool AI content generator, teacher and student assistants · Cinekholm and Demostra: GPT-6 Luna

Per project

Remote · İstanbul, moving to Varese, Italy · Turkish or English · code stays yours

Tell me about the project

Path

Games first, then production frontend.

09/2023 — now

Software Engineer / Frontend Developer · Twin Science

Lead frontend developer of app.twinscience.com, Twin Science's AI-powered K-12 STEM platform — ten months of it alongside a senior developer, and 88% of today's code is mine. Angular 16 to 22, mobile Lighthouse from 50 to 94, a 33-tool AI content generator, streaming assistants, the quiz module and smart-board Presentation Mode, and zero to 2,191 running tests. On the same team I rewrote the admin panel in React 19 on my own, built the H5P players the games and videos run on, and develop our WordPress site. I also mentored two frontend interns who reported directly to me (2024 and 2026).

07/2023 — 09/2023

Frontend Intern · Twin Science

Component work across edtech products — the foundation of production-level frontend discipline.

11/2022 — 06/2023

IMAGINER Student Ambassador · Microsoft

Ran student workshops and technical sessions on Microsoft tooling at university and community events.

06/2022 — 02/2023

Junior Game Developer · Servo Studios

Owned the full lifecycle of five mobile games in Unity and C# — sole developer and product manager, shipping inside one-month deadlines.

05/2023

Software Engineer Intern · Beylikdüzü Municipality

A short public-sector term on implementation-focused engineering tasks.

2024 —

Science fields, Bilim Seferberliği · YGA

Twin-kit science workshops for children in the cities hit by the 2023 earthquakes, and platform and kit training for teachers.

Writing

Notes on migrations, performance work and what surfaces once real users arrive.

All writing

Credentials

Stack, education and languages.

The details, in one place and in plain text.

Stack

LanguagesTypeScript · JavaScript · Java · Python · C# · C/C++ · SQL

FrontendAngular · Signals · SSR · React · Next.js · React Native · RxJS · NgRx · MUI · Tailwind CSS · Tiptap · H5P

Backend & dataNode.js · Express.js · MongoDB · PostgreSQL · Redis · Socket.IO · WordPress

Testing & opsVitest · Playwright · Jest · GitHub Actions · Azure · Cloudflare · Sentry · Amplitude

ToolsUnity · Git · OpenAI · Cursor · Figma · Photoshop

Education

2026 —University of Insubria, Varese
MSc Computer Science

2020 — 2024Istanbul Aydın University
B.S. Software Engineering

2019 — 2020Yeditepe University
English Preparatory, C1

2018Erasmus+, Lisbon
Cultural Introduction Programme

Languages

EnglishC1

GermanA2

SpanishA1

Got something that has to hold up?

dev@yberkayarda.com

Or use the contact form LinkedIn

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