# hafencity.dev > hafencity.dev (legal name: hafencity.dev GmbH) is a software agency based in Hamburg's HafenCity district (Am Strandkai 8, 20457 Hamburg, Germany). The agency designs and builds custom web applications, mobile apps (iOS, Android, Flutter), AI integrations and AI agents, UX/UI design, and runs hands-on tech and AI workshops for teams. Managing directors: Hendrik-Hauke Rux and Marius Gill. Commercial register: Amtsgericht Hamburg, HRB 184802. The site is bilingual: German is the default language at https://hafencity.dev/ and English lives under https://hafencity.dev/en/. URLs below point to the English versions where available. Contact: moin@hafencity.dev · +49 40 18030691 · https://hafencity.dev/en/contact ## Services - [Services overview](https://hafencity.dev/en/services): Our services: custom web apps, mobile apps, workshops and AI integration – in-house, from a single team in Hamburg. - [Web Development](https://hafencity.dev/en/web-development): Web development from Hamburg: SaaS, internal tools and enterprise portals – tailored, performant, secure. - [App Development](https://hafencity.dev/en/app-development): Mobile app development from Hamburg: native iOS & Android, Flutter and React Native – from concept to App Store. - [Workshops](https://hafencity.dev/en/workshops): Hands-on workshops on AI, architecture and modern software development – ready for use in your team. - [AI Integration](https://hafencity.dev/en/ai-integration): Enterprise AI integration from Hamburg. We connect language models to ERP, CRM and data sources with EU hosting, OAuth 2.0 and full audit trails. - [AI Strategy](https://hafencity.dev/en/ai-strategy): AI strategy consulting from Hamburg. We deliver a prioritised roadmap, scored use-case backlog and a risk framework that boards and engineering can both rely on. - [AI Agents](https://hafencity.dev/en/ai-agents): AI agents from Hamburg. Autonomous workflows with traceable reasoning, structured tools and hard safety bounds — fit for regulated enterprise operations. - [Prompt Engineering](https://hafencity.dev/en/prompt-engineering): Prompt engineering from Hamburg. Eval-driven workflows, versioned prompts and measurable production quality for enterprise LLM applications. - [Generative AI](https://hafencity.dev/en/generative-ai): Generative AI from Hamburg. Productive image, text, code and document workflows with custom brand adapters, EU hosting and full provenance. - [Design](https://hafencity.dev/en/design): Product design from Hamburg: UX/UI, design systems, sprints, prototyping, user testing and accessibility — researched, documented, measurable. - [UX/UI Design](https://hafencity.dev/en/ux-ui-design): UX/UI design from Hamburg: research, wireframes, high-fidelity mockups and interaction design for web and mobile products that get used. - [Design System](https://hafencity.dev/en/design-system): Design systems from Hamburg: tokens, components, documentation and engineering hand-off — one source of truth for brand, design and code. - [Design Sprint](https://hafencity.dev/en/design-sprint): Design Sprint from Hamburg: five facilitated days from problem to a tested prototype — with a documented decision your steering committee can read. - [Prototyping](https://hafencity.dev/en/prototyping): Prototyping from Hamburg: from paper sketch to interactive high-fidelity prototype — at the right level of fidelity for each project stage. - [User Testing](https://hafencity.dev/en/user-testing): User testing from Hamburg: moderated tests, heatmaps, session replay and interviews with real users — with documented findings your team can act on. - [Accessibility](https://hafencity.dev/en/accessibility): Accessibility from Hamburg: WCAG 2.2 audits, EAA-compliant implementation, screen-reader tests and documented fixes for web and mobile products. - [Development](https://hafencity.dev/en/development): Custom software engineering from Hamburg: web apps, mobile apps, backend services and DevOps — built for compliance, performance and the long run. - [Web App Development](https://hafencity.dev/en/web-app-development): Custom web app development in Hamburg: SaaS dashboards, internal tools and customer portals — Next.js, React, TypeScript, accessible by default. - [WebView App Development](https://hafencity.dev/en/webview-app-development): WebView app development from Hamburg: wrap your existing web app in a native iOS and Android shell — push, biometrics, store distribution. - [Hybrid App Development](https://hafencity.dev/en/hybrid-app-development): Hybrid app development from Hamburg: Ionic and Capacitor apps that ship to iOS and Android from one codebase — close to native, web speed. - [Cross-Platform Development](https://hafencity.dev/en/cross-platform-development): Cross-platform app development from Hamburg: React Native and Flutter for iOS, Android and Web — shared logic, native performance, single team. - [Backend Development](https://hafencity.dev/en/backend-development): Backend development from Hamburg: APIs, event pipelines and data models — observable from day one, GDPR and ISO-27001-ready, built for load. - [Maintenance & Support](https://hafencity.dev/en/maintenance): Software maintenance from Hamburg: a fixed pool of hours for security updates, monitoring, backups and continued development — with an hours calculator, SLA and monthly cancellation. - [Security Review](https://hafencity.dev/en/security-review): Free security review: concrete vulnerabilities in your code, dependencies and infrastructure. A prioritised, confidential report — no obligation, from Hamburg. ## Key articles - [Free Security Check: Getting Your Software Reviewed Safely](https://hafencity.dev/en/blog/free-security-check-get-software-reviewed): Get your software reviewed for free: what a free IT security check can do, where its limits are, and how to tell a genuine offer from a disguised sales pitch. - [Build, buy, or agency? The Mittelstand software decision](https://hafencity.dev/en/blog/build-buy-or-agency-software-decision): Build, buy, or agency? Only 3.6% of German SMEs build AI in-house. When standard software, in-house build or a partner fits — with current 2026 data. - [The EU AI Act for SMEs: using AI creates duties too](https://hafencity.dev/en/blog/eu-ai-act-smes-deployer-obligations): The EU AI Act for SMEs: even deployers who only use AI have duties. Risk classes, the timeline from 2 February 2025 and fines up to EUR 35 million explained. - [AI in the German Mittelstand 2026: numbers, sectors, opportunities](https://hafencity.dev/en/blog/ai-in-the-german-mittelstand-2026): AI in the German Mittelstand 2026: around 20 percent use AI (780,000 firms), large 66.3 vs. small 35.6 percent. Sectors, use cases and where the opportunities are. - [Software and AI Despite the Skills Shortage: Build Without a Team](https://hafencity.dev/en/blog/software-and-ai-despite-skills-shortage): The skills shortage is the No. 1 barrier to Mittelstand digitalisation: 53% lack technical know-how, 51% lack staff. How to ship software and AI anyway. - [Will AI replace your software agency? Why the opposite is true](https://hafencity.dev/en/blog/will-ai-replace-your-software-agency): Will AI replace your software agency? AI gets you to 70% of an app — the last 30% stays engineering. What that means for your project in 2026. - [AI in software development: why an agency ships faster and better with it](https://hafencity.dev/en/blog/ai-software-development-agency-faster-better): AI measurably amplifies strong teams – DORA +21% tasks, +98% PRs, Copilot 55.8% faster. How an agency turns that speed into better outcomes, not just more code. - [The risks of AI code generation — and how an agency keeps them in check](https://hafencity.dev/en/blog/risks-of-ai-code-generation-agency-safeguards): 45% of AI code carries flaws, 19.7% name invented packages: we show the real risks of AI code generation — and how an agency keeps them in check. - [Software Audit 2026: Code Quality, Security, Cost and Roadmap](https://hafencity.dev/en/blog/software-audit-code-review-security-cost-roadmap): Software audit 2026: when it pays off, what it checks and what it costs – from a 3,000 EUR quick check to a 40,000 EUR security audit, plus NIS2 and the Cyber Resilience Act. - [Software Maintenance 2026: Cost, Operations and Roadmap](https://hafencity.dev/en/blog/software-maintenance-cost-operations-roadmap): What software maintenance costs in 2026: the 15–25% of build-cost rule, monthly ranges in EUR, SLAs, security updates and a continuous-development roadmap. All articles: https://hafencity.dev/en/blog (German originals at https://hafencity.dev/blog) ## Other pages - [About](https://hafencity.dev/en/about): Meet our team: project managers, designers and developers from Hamburg building web and mobile apps with measurable impact. - [Projects & references](https://hafencity.dev/en/projects): Selected client projects: SaaS, mobile apps, platforms and AI solutions – with measurable results. - [Careers](https://hafencity.dev/en/career): Join hafencity.dev. Open positions for developers, designers and project managers in Hamburg. - [Contact](https://hafencity.dev/en/contact): Talk to our team in Hamburg. We respond within one business day – via email, phone or scheduled call. - [Imprint](https://hafencity.dev/impressum): Legal information for hafencity.dev GmbH. - [RUDI](https://hafencity.dev/rudi): RUDI is a separate product by hafencity.dev — a German-language iOS party game app for groups aged 13+ (not related to the agency's client services). ## Sitemaps - https://hafencity.dev/sitemap.xml (index: sitemap_de.xml and sitemap_en.xml)