ZeroFS
"The filesystem that makes S3 your primary storage" — a Rust server exposing S3-compatible object storage as a real POSIX filesystem over NFS, 9P, and NBD, no FUSE. Source: github.com/Barre/ZeroFS, 2026-06-15
What it is
ZeroFS (by Barre, ~2K★, Rust; originally built for merklemap.com) layers POSIX semantics — in-place writes, appends, permissions, timestamps — on top of plain S3 by storing data in its own layout (an internal LSM-tree backend) rather than mapping objects 1:1. Access modes: Source: github.com/Barre/ZeroFS README, 2026-06-15
- NFS — mount on any OS (macOS/Linux/Windows/BSD), no extra client software.
- 9P — higher-performance alternative with better POSIX FSYNC accuracy.
- NBD — raw block devices: run ZFS, databases, or any filesystem directly on S3.
- Always encrypted — XChaCha20-Poly1305 + LZ4/Zstd compression; multi-layered caching for microsecond latencies.
vs AWS Mountpoint-s3 (read-optimized, 1:1 object mapping, no in-place modify/append/chmod): ZeroFS is general-purpose read+write with full POSIX (8,662 pjdfstest cases in CI), mean latencies ~0.86–1.42 ms in its own benchmarks. Source: zerofs.net/docs/zerofs-vs-mountpoint-s3, 2026-06-15
Relevance to Dedalus
Prior art for Dedalus FS: both make object storage behave like a workspace filesystem. The contrast is instructive — Dedalus FS is single-writer (SQLite metadata + content-addressed chunks, instant COW clones) and explicitly not multi-writer NFS or block storage, whereas ZeroFS leans into NFS/9P/NBD block access. ZeroFS's NBD-block angle parallels LSVD's bottomless block device. Source: compiled, 2026-06-15
Timeline
- 2026-06-15 | Added (Kevin) as a filesystem-on-S3 reference alongside JuiceFS; linked to the Dedalus storage stack. Source: User, 2026-06-15; github.com/Barre/ZeroFS