Version 1.0 is available now! See the newest documentation here.

SLSA Specification

SLSA is a specification for describing and incrementally improving supply chain security, established by industry consensus. It is organized into a series of levels that describe increasing security guarantees.

This is version 1.0-rc1 of the SLSA specification, which defines the SLSA levels. For other versions, use the chooser at the bottom of this page. For the recommended attestation formats, including provenance, see “Specifications” in the menu at the top.

About this release candidate

This release candidate is a preview of version 1.0. It contains all anticipated concepts and major changes for v1.0, but there are still outstanding TODOs and cleanups. We expect to cover all TODOs and address feedback before the 1.0 final release.

Known issues:

  • TODO: Use consistent terminology throughout the site: “publish” vs “release”, “publisher” vs “maintainer” vs “developer”, “consumer” vs “ecosystem” vs “downstream system”, “build” vs “produce.

  • Verifying artifacts and setting expectations are still in flux. We would like feedback on whether to move these parts out of the build track.

Table of contents

Page Description
What’s new in v1.0 What’s new in SLSA Version 1.0.
Security levels Overview of SLSA, intended for all audiences. If you read one page, read this.
Guiding principles Background on the guiding principles behind SLSA.
Terminology Terminology and model used by SLSA.
Producing artifacts Detailed technical requirements for producing software artifacts, intended for system implementers.
Verifying build systems Guidelines for securing SLSA Build L3+ builders, intended for system implementers.
Verifying artifacts Guidance for verifying software artifacts and their SLSA provenance, intended for system implementers and software consumers.
Threats & mitigations Specific supply chain attacks and how SLSA helps.
FAQ Questions and more information.
Future directions Additions and changes being considered for future SLSA versions.