“Expectation creates reality.”
— The rule I build by
ROTTERDAM / MENDIX / SOLO BUILDER
Currently shipping
Product building
is a game.
I play to ship.
Rotterdam-based builder. Mendix by day — making mobile teams ship faster. Indie by instinct — 9 apps live on the App Store, each solving a real problem I've faced. Taste, systems, and momentum. That's the loop.
SHIPPED & LIVE — 9 APPS
Glow Up
Crypto Signal
GlowMe
MyDietPal
Posture
Packing List
Linlan
Sticky Notes
Vocabulary
Glow Up
Crypto Signal
GlowMe
MyDietPal
Posture
Packing List
Linlan
Sticky Notes
Vocabulary
Harun Karahan
Builder in Rotterdam. Obsessed with simple, shipped, useful.
NEXT DESTINATION
Málaga 🇪🇸
Andalusia. Warm sun, Picasso, slow mornings.
GAME LOOP
- 01 Observe
- 02 Simplify
- 03 Build
- 04 Release
9
Apps shipped
Live on App Store
9
Live on App Store
Across Health, Education, Travel, Utilities
3
Tech stacks
React Native · React · Angular
∞
Game loops
Observe → Ship → Repeat
THE HUMAN BEHIND THE SHIPPING
More than a portfolio. A system for building.
No fluff. Just values, focus, and a few fun obsessions that keep the work honest.
RotterdamMendixSoloDisciplined
Mobile platform delivery for teams building apps inside Mendix. Reusable foundations, faster releases.
- Ethic — do it right when no one's watching
- Equalism — everyone gets a fair start
- Meaning — ship things that matter
- Fun — if it's not fun, you're doing it wrong
One mobile foundation. Multiple product teams. One consistent experience.
JOURNEY
Travel keeps the eye sharp and the work honest.
- Fitness & nutrition
- Travel & cities
- Ambient sounds
- Language learning
- Product strategy
- Systems thinking
“Simplicity is the ultimate sophistication.”
— Leonardo da VinciGlow UpHealth
CryptoUtilities
GlowMeBeauty
VocabularyEducation
MyDietPalHealth
PostureFitness
Packing ListTravel
LinlanEducation
Sticky NotesUtilities
9 independent apps. Each solves a real problem I've faced — from health to learning to travel.
- Systems thinking
- Product strategy
- Behavioral design
- Language & cognition
- Stoic philosophy
PRODUCT SHELF — SHIPPED, NOT SLIDES
One shelf. 9 products. All live on the App Store.
Like PostHog's toolbox — every product does one job well. Verified from my developer page →
HEALTH & FITNESS
LIVE
Glow Up: Skincare & Exercises
Mobility, Nutrition, Longevity — daily food, movement & mindfulness plans.
Open in App Store →
UTILITIES
LIVE
Crypto Signal & Calculator
Crypto Signals & Price Tracker — BTC, ETH, Solana and more.
Open in App Store →
HEALTH & FITNESS
LIVE
GlowMe - Skin Beauty Coach
Face Scan & Skincare Routines — symmetry, puffiness, tone.
Open in App Store →
EDUCATION
LIVE
Learn New Vocabulary - Words
Daily Practice With Flashcards — 1000 words, audio & video examples.
Open in App Store →
HEALTH & FITNESS
LIVE
MyDietPal - Low Calorie Foods
Tracker, Counter, Recipes, BMI — simple nutrition & calorie tracking.
Open in App Store →
HEALTH & FITNESS
LIVE
Posture - Strength Tracker
Back Pain & Strength Coach — guided plans for posture & alignment.
Open in App Store →
TRAVEL
LIVE
Holiday & Travel: Packing List
Smart Checklist & Trip Planner — never forget a thing again.
Open in App Store →
EDUCATION
LIVE
Vocabulary Flashcards: Linlan
Vocab Trainer & Master — 10 languages, translation & quizzes.
Open in App Store →
UTILITIES
LIVE
Sticky Notes - Widget, Notepad
Memo Calendar Photo & List — widgets, notepad & sticker PDF.
Open in App Store →
CONTACT — NO SALES PITCH
If the game feels aligned, let's talk.
I'm Harun — Rotterdam, Mendix, product loops. Fast replies, honest takes. Email is best.
Usually replies within a day. No recruiters spam, just real conversations.