Full-Stack Engineer (Mobile + Web + Serverless)

This is a remote job position. Vacancy: Full-Stack Engineer (Mobile + Web + Serverless) Collaboration Conditions: Modality: 100% remote (Flexible schedule compatible with European time zones). Type of collaboration: Freelance. Start date: Immediate. Initial duration: ~75 working days (≈ 3.5 months), with a high probability of continuation in maintenance and product evolution phases. Tracking tools: Transparent time tracking via Hubstaff. What will you do in this project? We are looking for a versatile profile to join the development of an integrated omnichannel digital ecosystem. Your main responsibilities will be: - Design and implement web applications, mobile apps, and interactive terminals on top of a unified backend. - Build and maintain the project's REST API and data model in non-relational environments. - Integrate both digital and physical terminal payment gateways across multiple channels. - Develop a custom CMS focused on campaign management, rewards, and user loyalty. - Implement REST-based data integrations and synchronizations with third-party systems (POS/ERP). - Work with agile methodologies and AI-assisted development tools (Claude Code, Cursor) as a daily productivity engine. What we expect from you: Essential Requirements: - Experience: More than 5 years developing and deploying digital products in real production environments. - Main Technical Stack: Solid experience in at least two of them.