OneLake APIs: Bring your apps and build new ones with familiar Blob and ADLS APIs

[tompeplow]

OneLake is the unified data lake for Microsoft Fabric, designed to simplify data management and accelerate analytics across your organization. The best part is, OneLake speaks the same language your applications already do.

With support for the ubiquitous Azure Data Lake Storage (ADLS) or Blob Storage APIs, OneLake makes it easy to bring your existing applications and tools into the Fabric ecosystem without rewriting a single line of code. If your apps already work with Azure Blob Storage or Azure Data Lake Storage – like Azure Storage Explorer – they’ll feel right at home in OneLake. All you have to do is use the OneLake endpoints:

https://onelake.dfs.fabric.microsoft.com/<workspace>/<item>.<itemtype>/<path>/<fileName>

https://onelake.blob.fabric.microsoft.com/<workspace>/<item>.<itemtype>/<path>/<fileName> 

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Why This Matters

Organizations have invested heavily in applications, scripts, and workflows built on Blob and ADLS APIs. Migrating to a new platform often means costly rewrites and long timelines—but not with OneLake. By supporting these familiar APIs, OneLake ensures:

• Seamless migration: Move your workloads to OneLake without changing your existing code.
• Immediate compatibility: Your tools, SDKs, and scripts that use Blob or DFS APIs just work.
• Faster innovation: Focus on building new capabilities instead of re-engineering old ones.

This compatibility means you can start leveraging the power of Microsoft Fabric and OneLake today, without disruption.

See it in Action

The OneLake APIs in Action guide shows you exactly how this works. You’ll find an end-to-end C# example using the Azure Blob Storage and Distributed File System (DFS) libraries with OneLake, plus tips for getting good performance and best practices when working with a cloud file system. The guide uses open mirroring to replicate data from an on-premises system to OneLake Delta tables. It’s the perfect starting point for developers and data engineers who want to make the most of OneLake’s capabilities.