Senior Mobile Developer

Chalice LTD is expanding its team and is looking for a new Senior Mobile Developer with a passion for new technologies to join an exciting and growing project.

The project is fast-growing sport startup, focused on tennis and AI features to bring the most innovative and cutting age experience for their mobile app users in order to improve the game to the next level. 

Responsibilities 

- Develop the mobile app (iOS/Android) incl. video capture, uploads, on-device UX, and offline capabilities. 

- AI platform / backend integration: video ingestion, analysis/inference pipelines, API design, scaling & observability. 

- ML/AI integration: integrate CV/pose/racket-tracking models (on-device and/or cloud); optimize inference (latency, cost). 

- Security & privacy by design (GDPR-compliant), clean permissions/access model. Close collaboration with Coaching/Design on UX flows (Record → Insight → Drill → Progress). 

Must-haves 

- 5+ years as a software developer (with substantial mobile and backend/cloud experience). 

- Hands-on with React Native or Flutter or native (Swift/Kotlin). 

- Solid backend/API experience (Node.js/TypeScript or Python/FastAPI/Django), cloud (AWS/GCP/Azure), CI/CD. 

- Familiar with computer vision / ML integration (e.g., PyTorch/ONNX/TFLite, OpenCV, MediaPipe, pose estimation). 

- Strong in architecture, testing, performance, observability. Self-starter, product thinking, build–measure–learn mindset. 

- Fluent English (English advantageous; team distributed across Germany). 

Nice-to-haves 

- Experience with video pipelines (FFmpeg, HLS, WebRTC, upload/transcode). 

- Edge/on-device inference (TFLite/Metal/NNAPI), GPU/accelerators. 

- Knowledge of App Store/Play Store release processes, Crashlytics, in-app purchases/subscriptions. 

- Passion for tennis or racket sports.