Browse Microsoft Fabric OneLake from Finder. Like OneDrive or Google Drive — but for your data lake. Multiple accounts in multiple tenants, side by side, with a single Homebrew install.
Pre-release, under active development.
📖 Documentation, screenshots and walkthroughs: ofem.debruyn.dev
brew install --cask sdebruyn/ofem/ofemRequires macOS 14 Sonoma or later on Apple Silicon. No system-level changes, no extra dependencies, no admin password.
- Multiple OneLake accounts across multiple Microsoft Entra tenants visible side by side in Finder.
- Online-only placeholders by default — files stream on demand, cached locally for instant reopen.
- Drag, drop, double-click, save in any app. Spotlight indexing and Quick Look work out of the box.
- One Finder sidebar entry per account (
OneLake — work,OneLake — client-a, …) so workspaces from different tenants never collide. macOS places each one under~/Library/CloudStorage/OneLake-<alias>/, the same way OneDrive and Google Drive do.
Things managed by Microsoft Fabric and not exposed through the file system: creating or renaming workspaces, managing permissions, changing the schema of Delta tables. Those still go through the Fabric portal.
OFEM ships with a multi-tenant Entra App Registration that works for most users. Tenants that block third-party multi-tenant apps can supply their own client ID in Add Account → Advanced — see Custom App Registration for the exact registration settings.
Issues · Discussions · Security (private)
The engine, auth, cache, and sync logic live in the OfemKit Swift Package, which runs
inside the File Provider Extension process. The host app communicates with the extension
via standard Apple XPC (NSFileProviderService).
- Architecture overview — process model, source layout, and design decisions
- Authentication design — MSAL flow, multi-tenant model, token audiences, Keychain cache
Open source under the MIT License. See CONTRIBUTING.md for setup, and ofem.debruyn.dev/design/overview/ for the architecture overview.
Sponsor OFEM to help cover the Apple Developer Program membership and Azure costs.