# Let's Seal

> Let's Seal is a self-hosted, open-source platform for cryptographically sealing any file — PDFs, images, XML, email, code — proving integrity, time, and issuer identity.

- **Category:** Authentication
- **Licence:** Apache-2.0
- **Latest version:** v0.1.0
- **Open source:** oss
- **Languages:** Typescript, JavaScript
- **Platforms:** Build from Source
- **Tags:** E Signature, Self Hosted, X509, Apache 2.0, S/mime, Certificate authority, Digital Signature, Supply Chain Security, Open Standard, Document Sealing, Pades, C2pa, XML Dsig, Cades, Opentimestamps, Certificate Transparency, Content Credentials, Document Authentication, Sigstore

## Description

Let's Seal provides an open standard for proving file authenticity — that a file is unchanged, certified by a known authority, and existed by a certain date. It handles PDFs (PAdES), media (C2PA), XML (XML-DSig), email (S/MIME), generic files (detached CAdES/CMS), and software artifacts with attestations. The stack includes a certificate authority as code, a FastAPI signing service holding the intermediate key, and a Next.js web app with dashboard, API, and verification portal. Verification is free, keyless, and works offline with standard tools. Run by Experimental Open Works as a public-benefit project. Self-hosting gives full control of your CA and keys; seals stay verifiable forever. Current release v0.1.0 (pre-1.0).

## Links

- [Homepage](https://github.com/letsseal/letsseal)
- [Website](https://letsseal.org)
- [Documentation](https://letsseal.org/site/docs)
- [GitHub Repository](https://github.com/letsseal/letsseal)
- [Getting Started Guide](https://letsseal.org/site/getting-started)
- [Developers Guide](https://letsseal.org/site/developers)
- [Self-hosting Guide](https://letsseal.org/site/open)
- [Verification Portal](https://verify.letsseal.org)
- [Discussions](https://github.com/letsseal/letsseal/discussions)

---
Source: https://selfhost.directory/project/letsseal