# Barre/ZeroFS

ZeroFS: A log-structured filesystem for S3.  ZeroFS serves S3-compatible buckets as POSIX filesystems over NFS and 9P, or as raw block devices over NBD.

Repository: https://github.com/Barre/ZeroFS
Canonical: https://ross.abutalabs.com/products/zerofs
Homepage: https://www.zerofs.net
Language: Rust
License: AGPL-3.0
License Family: copyleft
Topics: nfs, nfs-server, nbd, 9p, 9p2000, plan9, csi-driver, block-storage, distributed-file-system, filesystem, fuse, kubernetes, object-storage, posix, s3, software-defined-storage, cloud-storage, lsm-tree, log-structured-filesystem
Last push: 2026-08-26T14:01:59+00:00

## Health v2 (maintenance only)
Score: 81/100 (v2, computed 2026-09-03T02:39:23.370411+00:00)
- activity 99, release rhythm 87, longevity 29
- inputs: {"age_days": 415, "days_push": 7, "days_rel": 7, "gap_med": 1.0, "n_releases_24m": 151}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3003, forks 113 (observed 2026-08-28T04:07:37.499535+00:00)

## What it is
ZeroFS is a log-structured filesystem written in Rust that turns S3-compatible object storage (Amazon S3, GCS, Azure Blob, or any S3-compatible store) into a POSIX filesystem. It serves files over NFS and 9P and raw block devices over NBD from a single userspace process, with built-in compression (zstd/lz4) and encryption (XChaCha20-Poly1305).

## Use cases
- mount an s3 bucket as a posix filesystem
- use object storage as a block device for vms
- store kubernetes persistent volumes on s3
- run a shared filesystem backed by cloud object storage
- encrypt and compress files stored in s3
- replace expensive cloud block storage with s3
- access s3 files from macos or windows over nfs

## When to choose
- you want POSIX-conformant filesystem semantics on top of S3 without running a database
- you need encrypted, compressed storage where data is encrypted before it leaves the machine
- you need block devices (NBD) or Kubernetes CSI volumes backed by object storage
- you have workloads with hundreds of millions of small files and want near-raw-S3 throughput
- you want high availability with leader/standby failover over the same bucket

## When to avoid
- you need strict fsync durability guarantees - NFS COMMIT semantics can return before data reaches S3 (use 9P instead)
- you need a simple one-off file sync tool rather than a full filesystem server
- your workload requires very low latency metadata operations and you have no local disk for caching
- you cannot run a persistent userspace server process and only want ad-hoc bucket access

## Facets
- artifact type: application
- maturity: active
- function: file-system, object-storage, cryptography, compression, caching, backup
- domain: cloud-computing, self-hosted, infrastructure-as-code, files, microservices
- platform: windows, bsd, rust, self-hosted, cloud
- tags: s3, nfs, 9p, nbd, posix-filesystem, log-structured, lsm-tree, block-device, csi-driver, fuse, object-storage-gateway, encrypted-storage, storage, linux, macos, docker, kubernetes

## Member repositories
- Barre/ZeroFS (main) score 81

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:37.499535+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:30:25.007991+00:00, confidence not recorded.
  - readme: https://github.com/Barre/ZeroFS (fetched 2026-08-28T04:07:37.499535+00:00, sha 85b7a8c91889)
  - homepage: https://www.zerofs.net (fetched 2026-08-29T09:45:45.665600+00:00, sha 78b79a93b65b)
  - site_page: https://www.zerofs.net/docs (fetched 2026-08-29T09:45:45.668544+00:00, sha 10d6024cdac6)
  - site_page: https://www.zerofs.net/docs/quickstart (fetched 2026-08-29T09:45:45.670561+00:00, sha b6dc08b353cb)
  - registry_crates: https://crates.io/api/v1/crates/zerofs (fetched 2026-08-29T09:45:45.672317+00:00, sha d93a723f96f6)
- Data as of 2026-08-30T08:39:29.467469+00:00.