Art Director & Developer. The same person designs the screens and writes the code. I build iOS apps, WooCommerce stores, payment integrations and custom panels for businesses.
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I'm Hasan Cemil Acar, known online mostly as rentonhead. I'm an independent Art Director and developer based in Istanbul. For brands, businesses and my own products I design the screens and write the code.
On the technical side I build iPhone apps with Swift/SwiftUI, web interfaces with React & Next.js, and stores, payment gateways and order panels on WordPress/WooCommerce. A café POS system, a school payment panel and a meal-card integration are among the projects running live today.
On the design side I create brand identities, interfaces and App Store visuals with Figma and Adobe Creative Suite. Doing both means nothing gets lost between the design and the build.
Each area has its own page: what gets delivered, which decisions are made, and what drives time and price.
Fast company websites that look right on a phone and make it easy to reach you. Static or WordPress is decided by how often you will update the content.
View service ↗02 · E-commerceWooCommerce stores with a clear category structure, virtual POS, shipping and a checkout that works. Retail and wholesale can run as separate stores on one install.
View service ↗03 · WordPressSmall plugins built for your business: payment gateways, order panels, roles and permissions, integrations. One maintainable piece of code instead of five patched-together plugins.
View service ↗04 · iOSNative iPhone apps in SwiftUI. Screens, data flow, subscriptions and the App Store release are planned together from the start.
View service ↗05 · App StoreFor most users your App Store page is the app's first demo. Screenshot order, title and subtitle directly affect the download decision.
View service ↗06 · SEOThe technical groundwork that helps Google and AI tools like ChatGPT understand your site: structured data, speed, indexing and measurement.
View service ↗07 · DesignScreens where people find the next step without thinking. Figma prototypes and developer-ready designs, and the code too if you need it.
View service ↗The five systems below are live right now and used by real businesses. Each case explains what was solved and why each decision was made. All case studies ↗
An ordering system built to escape marketplace commission: a meal-card payment gateway, a live kitchen panel, courier handoff and role-based staff access.
Read the case ↗02 · Coffee · retail + wholesaleTwo stores on one WordPress install that do not undermine each other: public retail and login-gated wholesale, plus personalisation and a blend tool.
Read the case ↗03 · Education · paymentsCollections for a 285-student school: two bank virtual POS integrations, a bank-transfer approval flow and an SMS panel fed by student data.
Read the case ↗04 · Café · POS + loyaltyTill, kitchen, reporting and loyalty on one dataset: audited voids, a stamp and points engine, and a QR menu fed by the POS.
Read the case ↗05 · Corporate · 3 divisionsA static corporate site separating construction, furniture and logistics under one identity without any of them suppressing the others.
Read the case ↗Every note comes from a problem hit on real work: the symptom, the root cause and a verified fix. All technical notes ↗
Meal-card payments in WooCommerce need a custom gateway, not a plugin. How to build the flow, the security mistake almost everyone makes, and order states.
Read the note ↗02 · WooCommerce · PaymentsThe gateway is enabled in settings but missing at checkout. Usually the block checkout: classic gateways are not listed there unless registered.
Read the note ↗03 · WooCommerce · Virtual POSWith 3D Secure the result returns through the customer's browser. Close the tab and the card is charged while the order stays pending. Ask the bank.
Read the note ↗04 · WooCommerce · DebuggingProducts go into the cart but checkout shows it empty. The cause is usually not caching but a speed plugin deferring every script: wp is not defined.
Read the note ↗05 · Product · POS ArchitectureWhat determines whether a café or restaurant POS works: void auditing, offline resilience, kitchen screen design, one price source and built-in loyalty.
Read the note ↗06 · Integration · SMSThe request returns 200 but no SMS arrives. Number format, sender approval, IP restriction and consent filtering are the usual culprits.
Read the note ↗Eight areas I work in. The same rule applies to all of them: how something looks and how it works are decided together.
I design brand, mobile and web screens with Figma, Photoshop, Illustrator and After Effects.
I build logo, typography, palette, grid and usage guidelines as one visual language.
I build fast, maintainable native iPhone apps with Swift and SwiftUI.
I set up WooCommerce and WordPress stores with theme, payments, product management and speed thought through.
Fast websites with React, Next.js and Tailwind CSS, and the data side with Python and Firebase when needed.
I prepare App Store screenshots, launch visuals and store copy.
I write clean, purpose-built plugins for WordPress, WooCommerce and Elementor in PHP.
With structured data, technical SEO and GEO I make sure Google and AI tools understand a site correctly.
Every job goes through five steps, with the same person on it from the first call to delivery. Durations depend on size: a plugin can take days, a full product a few months.
We start with a focused conversation: what you are building, who it is for, why it matters, where competitors are looking, and where your product should stand. The phase ends with a written note, a concrete scope and a clear timeline.
I propose two or three directions for visual language and tone. We pick one together and deepen it in the following steps.
We move quickly from static screens to a clickable prototype. You give feedback on a screen you can touch, not on a PDF.
I write the interface I design. Whether it is SwiftUI, modern web or WordPress, having the same person draw and build the screen removes the gap between design intent and implementation.
We publish, document and hand over the files in a way an internal team can understand. The first three months stay open for small adjustments, measurement and polish.