# google/crfs

CRFS: Container Registry Filesystem

Repository: https://github.com/google/crfs
Canonical: https://ross.abutalabs.com/products/crfs
Language: Go
License: BSD-3-Clause
License Family: permissive
Archived: true
Last push: 2024-10-09T18:52:42+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 2721, "days_push": 693, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1405, forks 67 (observed 2026-08-28T04:04:38.102543+00:00)

## What it is
CRFS is a read-only FUSE filesystem that mounts container images directly from a container registry without pulling them locally first. It introduces the Stargz (seekable tar.gz) format, which indexes gzip streams so individual files can be read on demand over the network.

## Use cases
- mount container images from a registry without pulling them
- speed up container startup on cold nodes
- read individual files from a remote container image lazily
- avoid pre-pulling large containers in CI build VMs
- convert tar.gz images to the seekable Stargz format

## When to choose
- container image pull time dominates startup latency
- you want on-demand reads of image layers over a fast internal network
- you can build images in the Stargz format and mount them on Linux with FUSE

## When to avoid
- you need a writable container filesystem
- you're not on Linux or lack FUSE support
- you need broad ecosystem support - the project is in maintenance mode and alternatives like containerd stargz-snapshotter are more active

## Facets
- artifact type: application
- maturity: maintenance
- function: file-system, container-runtime, networking
- domain: cloud-computing, developer-tools, infrastructure-as-code
- platform: go, cli
- tags: fuse, stargz, container-registry, lazy-pulling, read-only-filesystem, docker-images, containers, linux

## Member repositories
- google/crfs (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:38.102543+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 2026-08-30T04:38:46.976233+00:00, confidence not recorded.
  - readme: https://github.com/google/crfs (fetched 2026-08-28T04:04:38.102543+00:00, sha b5ba6c60c2a8)
- Data as of 2026-08-30T08:39:29.467469+00:00.