Software Developer (m/w/d)

Full Stack Mobile Developer (Frontend & Backend) - Ayonic App (Kyaani GmbH)

Location: Berlin on site

Employment Type: mini job

About Ayonic (Kyaani GmbH)

Ayonic is a fast-growing, dual-app digital marketplace disrupting the German gig economy. We connect customers with professional, independent service providers - ranging from certified financial advisors to professional cleaning services. We operate a highly scalable platform consisting of a Customer App, a Provider App, and a robust backend that handles real-time lead generation, matchmaking, and commission structures.

The Role

We are looking for an experienced Full Stack Developer to take ownership of our app ecosystem. You will be responsible for identifying, debugging, and resolving both frontend Ul/UX issues and complex backend infrastructure challenges.

Because we leverage cutting-edge AI IDEs (Google Antigravity) for rapid development, you won't just be writing code line-by-line.You will act as a system architect - reviewing Al-generated artifacts, enforcing strict coding formats, and ensuring our database and API endpoints scale securely.

Key Responsibilities

Dual-App Management: Maintain, debug, and optimize both the Ayonic Customer App and the Ayonic Provider App.

Backend & API: Architect and troubleshoot backend logic, database schemas, and API endpoints (JSON format, strict state management).

Payment Integration: Securely manage our Stripe payment flows and commission-tracking logic, strictly adhering to our mock-key environment security protocols. Al Collaboration: Work directly with our Google Antigravity Al agents, writing clear Markdown (.md) rule files and reviewing task artifacts before execution.

Security & Compliance: Ensure all data handling complies with GDPR and German marketplace regulations, preventing data leaks or prompt injection vulnerabilities.

What You Bring

Proven Experience: Extensive background in Full Stack development, specifically building and maintaining mobile applications and robust backends. Full Stack development, specifically building and maintaining mobile applications and robust backends.

Tech Stack Mastery: Deep understanding of modern frameworks (eg, React Native, Node.js, TypeScript) and real-time infrastructure (eg, Socket.io).

Architectural Mindset: Ability to design secure database structures and API routes without

needing constant hand-holding.

Security First: Strong understanding of environment variable management, gitignore rules, and API key protection.

Adaptability: A willingness to embrace "agent-first" development workflows and code alongside autonomous Al tools.

Gehalt: 13,90€ pro Stunde

Arbeitsort: Vor Ort