# conorpp/u2f-zero

U2F USB token optimized for physical security, affordability, and style

Repository: https://github.com/conorpp/u2f-zero
Canonical: https://ross.abutalabs.com/products/u2f-zero
Language: C
License: NOASSERTION
License Family: other
Topics: u2f, hardware, security
Last push: 2022-09-01T01:17:44+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 3898, "days_push": 1463, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2451, forks 200 (observed 2026-08-28T04:06:52.957052+00:00)

## What it is
U2F Zero is an open source hardware U2F security token for two-factor authentication, built on a small USB device with secure key storage. It is explicitly unmaintained and superseded by the Solo FIDO2 key.

## Use cases
- build my own U2F security key
- two-factor authentication for Google and GitHub
- open source hardware 2FA token
- cheap hardware security key for keychain
- U2F token with unlimited registrations

## When to choose
- you want to build your own U2F token from open source schematics
- you need a low-cost hardware 2FA key and accept U2F-only support

## When to avoid
- you need FIDO2 or passwordless login - use SoloKeys instead
- you want a maintained, supported product
- you need protection against targeted physical side-channel attacks

## Facets
- artifact type: application
- maturity: abandoned
- function: security, auth, embedded
- domain: security, hardware, privacy
- platform: embedded, cross-platform
- tags: u2f, two-factor-authentication, hardware-token, fido, open-source-hardware, usb-security-key

## Member repositories
- conorpp/u2f-zero (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:52.957052+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 2026-08-30T02:30:12.427037+00:00, confidence not recorded.
  - readme: https://github.com/conorpp/u2f-zero (fetched 2026-08-28T04:06:52.957052+00:00, sha 3d898dae51de)
- Data as of 2026-08-30T08:39:29.467469+00:00.