# tonistiigi/binfmt

Cross-platform emulator collection distributed with Docker images.

Repository: https://github.com/tonistiigi/binfmt
Canonical: https://ross.abutalabs.com/products/binfmt
Language: Go
License: MIT
License Family: permissive
Topics: qemu, docker
Last push: 2026-08-24T12:33:05+00:00

## Health v2 (maintenance only)
Score: 95/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 87, longevity 100
- inputs: {"age_days": 2378, "days_push": 9, "days_rel": 86, "gap_med": 0.0, "n_releases_24m": 19}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1520, forks 105 (observed 2026-08-28T04:04:57.684689+00:00)

## What it is
A collection of QEMU user-mode emulator binaries distributed as Docker images that register cross-architecture emulators with the Linux binfmt_misc subsystem. It enables running and building container images for foreign architectures like arm64, riscv64, and s390x on any host.

## Use cases
- run arm64 docker images on x86 host
- build multi-architecture container images with buildx
- install qemu emulators for docker
- cross-compile containers for different cpu architectures
- test containers on arm, riscv64, s390x locally
- set up binfmt_misc handlers for foreign binaries

## When to choose
- you need to build or run multi-arch Docker images without native hardware
- you use Docker buildx or BuildKit and want automatic QEMU emulation
- you want a simple privileged-container command to install/uninstall emulators

## When to avoid
- you need full-system emulation rather than user-mode binary translation
- you cannot run privileged containers on your host
- you need maximum performance for foreign-architecture workloads (native runners are faster)

## Facets
- artifact type: cli-tool
- maturity: active
- function: container-runtime, developer-tools, cli, deployment
- domain: developer-tools, cross-platform
- platform: cli
- tags: qemu, binfmt-misc, emulation, multi-arch, buildx, buildkit, containers, devops, docker, linux

## Member repositories
- tonistiigi/binfmt (main) score 95

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:57.684689+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 2026-08-30T04:31:55.969962+00:00, confidence not recorded.
  - readme: https://github.com/tonistiigi/binfmt (fetched 2026-08-28T04:04:57.684689+00:00, sha c235959e9c47)
- Data as of 2026-08-30T08:39:29.467469+00:00.