Principal Software Engineer

Microsoft Corporation
Full-time Geneva, Switzerland other-general
Posted:
February 25, 2026
Location:
Geneva, Switzerland, Switzerland

Job Description

**Overview**



Microsoft 365 Copilot is transforming productivity by integrating large language models with user data, Microsoft Graph, and the web. At the core of this innovation is the **Substrate Intelligence Platform (DSX)** team, which powers **personalized, secure, and scalable Copilot experiences** across Microsoft 365—Teams, Word, Excel, PowerPoint, OneNote, and beyond.



Our team is pioneering the **infrastructure for tenant‑isolated fine‑tuning** , a foundational platform capability that enables customers to safely personalize Copilot agents using their own data. This includes support for leading OpenAI models (e.g., GPT‑5, O4 Mini) and open‑source models such as Qwen, Mistral, and GPT‑OSS.



We own the **end‑to‑end fine‑tuning platform via Heron** , spanning:



+ Data extraction and isolation

+ Secure training and evaluation workflows

+ Model deployment, migration, and lifecycle manag...

Apply for this Job

Submit your application for the Principal Software Engineer position at Microsoft Corporation.

Apply Now Save for Later

Job Overview

Job Type: Full-time
Location: Geneva, Switzerland
Posted: February 25, 2026
Deadline: March 30, 2026