Microsoft Build 2026: Fabric and Databases for AI Apps

Introduction

Microsoft is positioning data as the critical foundation for enterprise AI and multi-agent applications. At Build 2026, the company announced new Microsoft Fabric and Microsoft Database capabilities designed to give developers a faster path from prototype to production while maintaining enterprise security, governance, and scale.

What’s new at Microsoft Build 2026

Rayfin for Microsoft Fabric

Microsoft introduced Rayfin, a new open-source SDK and CLI that helps developers and coding agents build production-ready application backends directly on Microsoft Fabric.

Key capabilities include:

• Defining data models, backend logic, and access policies in code
• Built-in backend services such as database and authentication
• Direct deployment to Microsoft Fabric
• GitHub-based workflows for app development and operations

Because Rayfin deploys to Fabric, application data lands in OneLake and becomes available across the broader Fabric data stack for analytics, real-time data, semantic models, and AI scenarios.

Azure HorizonDB public preview

Microsoft also announced Azure HorizonDB, a new fully managed, PostgreSQL-compatible database built for AI-powered applications, now in public preview.

Highlighted features include:

• Zone resiliency by default
• Elastic storage up to 128 TB
• Scale-out compute up to 3,072 vCores
• Sub-millisecond, multi-zone commit latency
• Built-in support for vector search and AI-oriented workloads
• Connectivity with Microsoft Foundry and Microsoft Fabric

This makes HorizonDB notable for organizations building transactional apps that also need modern AI features without stitching together multiple platforms.

PostgreSQL security and migration updates

Microsoft also shared two updates for Azure Database for PostgreSQL:

• Microsoft Defender for Cloud integration in preview for continuous security and compliance assessments
• New discovery and assessment tools for Oracle and PostgreSQL migrations, including readiness, sizing, and cost guidance

Why this matters for IT teams

For Azure administrators, architects, and platform teams, these announcements point to a more integrated Microsoft stack for AI application delivery. Fabric is becoming more than a data platform; it is increasingly part of the app backend story. At the same time, Microsoft is expanding database choices for both new AI-native apps and existing PostgreSQL modernization projects.

Next steps

• Evaluate Rayfin if your team is building internal apps or agent-based solutions on Fabric
• Review Azure HorizonDB preview for high-scale PostgreSQL and AI scenarios
• Enable Defender for Cloud integration for Azure Database for PostgreSQL where appropriate
• Use the new migration assessment tools to plan Oracle or PostgreSQL moves to Azure

These Build 2026 updates show Microsoft’s broader strategy: unify data, app backends, and AI services so organizations can scale agentic applications more safely and quickly.