Senior Software Engineer

Description de l’emploi

Le contenu du poste est libellé en anglais car il nécessite de nombreuses interactions avec nos filiales à l’international, l’anglais étant la langue de travail.

This job offer is accessible to all, regardless of gender.

Job title: Senior Software Engineer

Location: Paris - Hybrid (3 days a week onsite, 2 days work from home)

About the job

Sanofi is building a GenAI platform that helps product and business teams move from isolated AI experiments to secure, reusable, production-ready capabilities.

In a nutshell, a platform team creates the foundational layers and core building blocks that other teams rely on. We do not always provide direct business value ourselves; we help other technical teams focus on their own products by reducing repeated work, defining shared patterns, and building reusable capabilities.

Our platform covers several layers:

• Cloud-native building blocks, infrastructure, and deployment patterns
• APIs, SDKs, shared libraries, and internal tools
• Observability, security, access control, and operational standards
• Document ingestion, knowledge retrieval, and GenAI data pipelines
• Agent creation, agent orchestration, evaluation, and governance capabilities
• GenAI and agentic capabilities are a growing part of that mission. As highlighted in the AWS Sanofi success story, Concierge has evolved into a unified, agentic AI companion used across the company. The GenAI Platform team builds the foundations that make this kind of experience possible: reusable agent patterns, secure APIs, knowledge pipelines, evaluation frameworks, and governed orchestration layers.

One key project you will contribute to is AgentsHub, the central platform through which AI agents are registered, discovered, governed, and invoked. AgentsHub is designed to become the high-scale traffic layer between Sanofi applications, such as Concierge, and specialized agents that perform data retrieval, workflow automation, and system write-back.

What You Will Build

You will contribute to platform products built with TypeScript, Node.js, React, AWS services, Terraform, and modern GenAI integration patterns.

The role is hands-on and product-oriented. Depending on priorities, you may work on backend APIs, internal UIs, cloud infrastructure, shared libraries, automation tooling, agent registries, knowledge integrations, evaluation capabilities, or operational dashboards.

This is not a classical feature-team role where the scope is limited to one business application. You will work on foundational platform capabilities that enable many teams to move faster and build safer, more reliable GenAI products.

Job Description

Your key responsibilities will be

• Build and evolve reusable backend platform capabilities for GenAI applications, AI agents, knowledge retrieval, and cloud-native services
• Design and implement APIs, shared libraries, and automation workflows used by other engineering teams, including internal UIs and back-office tools for managing platform resources and agents
• Improve the reliability, security, observability, and scalability of platform services on AWS, integrating with GenAI building blocks such as Bedrock, Bedrock AgentCore, vector databases, knowledge bases, and agent interoperability protocols
• Contribute to production-readiness patterns: RBAC, audit logs, health checks, versioning, metrics, and operational tooling
• Collaborate with squads and product teams to turn repeated needs into reusable platform primitives, and document and advocate for platform capabilities across Sanofi

What we offer you:

• A fixed salary over 12 months, supplemented by a short-term incentive, as well as a collective variable compensation based on Sanofi Group results.
• Benefits & Well-being: Quality health insurance, extended maternity/parental leave (18/14 weeks), enhanced support in case of illness, teleconsultation and second medical opinion covered by Sanofi, as well as many other wellness programs to discover here.
• Work-Life Balance: 31 days of paid leave + RTT depending on your status, remote work up to 2 days/week
• Transportation: Public transport coverage up to 80%
• Savings & Retirement: Group Savings Plan and PERCOL with employer matching, and PERO
• Professional Development: Internal and international mobility opport