YAPPAIAbout Yappai
Software should adapt to businesses, not the other way around.
Yappai is a founder-led software engineering initiative based in Duisburg, North Rhine-Westphalia, Germany. Ahmet Cavus founded it with a practical motivation: businesses should be able to work with software that fits their processes and actual requirements.
Our vision
We aim to make custom business software more economically accessible, particularly for small and medium-sized enterprises in Duisburg and across NRW.
Modern architecture and responsible AI-assisted workflows may help make suitable implementation tasks more efficient. The goal is appropriate software that solves a business problem, with only the complexity the solution needs.
Fair & Honest Engineering
Successful cooperation should create value for both sides. Customers should receive software aligned with their actual needs; Yappai should receive fair compensation for professional engineering. Neither side should benefit unfairly at the other's expense.
We work toward transparent scope, clear responsibilities, understandable costs, realistic expectations and honest technical recommendations. Mutual respect and sustainable professional relationships matter more than selling unnecessary development work.
Genuine efficiency gains from modern development methods should be reflected in fair customer pricing. Economic suitability is assessed for each project, without guarantees of specific savings or fixed delivery times.
We aim to avoid unnecessary dependencies. Open-source technologies, established frameworks, customer-controlled infrastructure and portable architectures are considered where appropriate. Hosting, maintenance, support and third-party licenses may remain necessary; their costs should be transparent. Source-code ownership, usage rights and delivery conditions depend on the contract.
Fair & Honest Engineering is our business and engineering philosophy, not a certification or a new technical framework.
Technology with purpose
We select technology for technical suitability, business value and maintainability. AI is not chosen because it is fashionable, open source is not chosen solely because it is free, and commercial software is not rejected because it requires a license.
If an existing solution fits better, we recommend it. Not every business problem needs custom development.
Responsible AI-assisted engineering
AI development tools and agentic coding can support suitable activities. Customers purchase professionally engineered software, not access to coding agents. Architecture and technical decisions remain Ahmet Cavus's responsibility.
Generated code is reviewed appropriately. Testing, security considerations, maintainability and quality assurance remain essential. AI use must fit the project context, including the agreed handling of customer information, confidentiality and data protection requirements.
TECHNICAL OWNERSHIP
Ahmet Cavus
Founder & Lead Engineer
Professional software engineering since 2010
Ahmet Cavus is the founder of Yappai in Duisburg, North Rhine-Westphalia, and a Senior Software Engineer who has been developing professional software for production business and enterprise applications since 2010.
His experience with Kotlin/Android, Java, C#/.NET, React, TypeScript and Node.js is complemented by software architecture, system integration and responsible AI assistance.
He takes technical ownership from analysing and scoping a task through architecture and implementation to delivering a verifiable production result.
Every task is technically assessed, led and reviewed by Ahmet Cavus.
Yappai is currently founder-led. Businesses in Duisburg and across NRW speak directly with Ahmet; in-person meetings are possible by arrangement.
Focus areas
- Kotlin / Android
- Java
- C# / .NET
- React
- TypeScript / Node.js
- Software Architecture
- Production Enterprise Systems
- Healthcare / gematik / ePA
Healthcare & ePA
Hands-on experience integrating ePA functionality into existing Android applications and implementing gematik-related technical requirements.
Retail & Mobile
Hands-on project experience with Scan & Go, indoor navigation and mobile loyalty features. Focused on native Android development and integration with existing systems.
Have a question first?
Want to discuss how Yappai could help with your business software challenge?
Rooted in Duisburg. Focused on NRW.
Yappai seeks to build lasting professional relationships with businesses in Duisburg and across North Rhine-Westphalia. You speak directly with the founder responsible for the engineering. In-person meetings can be arranged to discuss your business-specific requirements and opportunities for long-term collaboration.
Let's Talk About Your Business Challenge.
Describe the workflow you want to improve or the software challenge you face. From Duisburg, Ahmet is personally available to discuss a suitable next step with businesses across NRW.
Discuss Your Software ProjectAn inquiry starts a personal conversation and does not commission any work.