# Offline credential verifiers

> Language-specific verification helpers and their trust boundaries.

Attestix uses a published canonical-JSON and Ed25519 credential profile. Shared fixtures test interoperability; they do not prove identical validation or trust policy across every API in every language. The profile differs from strict RFC 8785.

| Source repository | Scope |
| --- | --- |
| [Python](https://github.com/VibeTensor/attestix) | Identity and credential issuance, verification, documentation and provenance workflows. |
| [JavaScript / TypeScript](https://github.com/VibeTensor/attestix-js) | Offline verifier and delegation helpers; read parsing and chain-validation boundaries. |
| [Go](https://github.com/VibeTensor/attestix-go) | Credential verification and basic/full delegation helpers with different checks. |
| [Java](https://github.com/VibeTensor/attestix-java) | Caller-pinned trust inputs and supported signature/profile checks. |
| [R](https://github.com/VibeTensor/attestix-r) | Credential verification and delegation pair helpers. |
| [Rust](https://github.com/VibeTensor/attestix-rs) | Credential/delegation verification and checked canonicalization. |

The current npm package is `attestix`: install `attestix@0.4.2`. The legacy `@vibetensor/attestix` package remains at 0.2.0. Read each repository's installation and release notes; registry publication is separate from a GitHub release. JavaScript, Go and Java 0.4.2 are published; R and Rust have GitHub 0.4.2 releases, while CRAN and crates.io remain at 0.4.1 at this cutoff. The non-Python repositories are verifier libraries, not credential issuers.

## Verification responsibilities

Establish which issuer/key is trusted, what claims authorize, whether time/status checks are appropriate, and how replay is prevented. An embedded DID or caller-supplied key proves key control, not identity or permission. Offline verification cannot establish live revocation unless you provide a trusted status source and freshness policy.

The [browser verifier](/verify) uses npm `attestix` 0.4.2 with its documented local boundary checks and signature verification. It is not a legal conformity decision or a substitute for a trusted resolver.

See the [public conformance fixtures](https://github.com/VibeTensor/attestix/tree/main/spec/verify/v1) and each SDK README for exact APIs and limitations.