Senior Full-Stack Engineer – Payments & AI

About the role

ShareGroop is looking for a senior full‑stack engineer to drive the development of its payment orchestration platform. The role is remote, with occasional trips to Paris for onboarding, and reports directly to the CTO.

Key responsibilities

• Develop and enhance the platform using JavaScript/TypeScript, Node.js and Vue.js.
• Design and implement REST APIs, backend services and integration with PSPs and other payment APIs.
• Build robust asynchronous processing with queues, workers and idempotency handling.
• Write automated tests, conduct code reviews and support CI/CD pipelines.
• Monitor production, troubleshoot incidents and improve performance, security and reliability on AWS.
• Lead delivery for enterprise‑level integrations and scalable SMB solutions, from requirements gathering to go‑live.

Required profile

• 5–7+ years of full‑stack software engineering experience.
• Hands‑on experience in FinTech or payment processing, including PSP integration, webhooks, refunds and reconciliation.
• Proven ability to work autonomously, structure complex projects and interact with enterprise client IT teams.
• Professional English; French is a plus.

Required skills

• JavaScript / TypeScript
• Node.js
• Vue.js
• REST API design
• SQL / PostgreSQL
• Git
• Automated testing & CI/CD
• AWS Cloud Platform and distributed system architecture
• Payment APIs and PSP integration
• Familiarity with LLMs, AI agents or workflow automation (optional but valued)

What we offer

• Full‑time freelance contract to start, with potential evolution to a technical‑lead role.
• Opportunity to work on complex enterprise payment projects and scalable SMB solutions.
• AI‑driven engineering environment and remote‑first international team.
• Direct collaboration with the CTO and strong ownership of technical delivery.