







An architecture for collaborative applications where data is encrypted and operations are cryptographically verifiable.
CryptPad: end-to-end encrypted collaboration suite
CryptPad: end-to-end encrypted collaboration suite

CryptPad: end-to-end encrypted collaboration suite
CryptPad: end-to-end encrypted collaboration suite

Architecture
Overview of Ente's end-to-end encrypted architecture—learn how your data is encrypted on-device, securely shared, and safely stored using cryptography.

Permissioned Data Diary 1: To Encrypt or Not to Encrypt - Daniel's Leaflets
The first in a series of posts about major design decisions along the way to a permissioned data protocol for atproto.
Cryptomator - Free & Open-Source Cloud Storage Encryption
Cryptomator is an open-source encryption tool for secure cloud storage. Protect your privacy for free on Dropbox, Google Drive, OneDrive, and more.

attested.network — Proof of Payment for ATProtocol
An open specification for decentralized, cryptographically verifiable proof of payments.
Decrypting Matrix – Where Do Rooms Go?
Matrix has been running private rooms on open protocols for a decade, and they ended up inside European governments. This piece is about why happened, and why it does not have to be the result of the various projects for private data and rooms on the open social web too.

Permissioned Data Diary 2: Buckets - Daniel's Leaflets
The second in a series of posts building up a solution to permissioned data on atproto. We introduce buckets: a new protocol primitive for creating a shared social context.
Spaces as Layers - Nick's Blog
Public anchor records paired with sidecar records in permissioned spaces give ATProtocol apps a composable pattern for blending open discoverability with controlled access.
ATProtocol Attestations: Cryptographic Signatures for the Decentralized Web - Nick's Blog
This post introduces the formal ATProtocol attestation specification, a framework for adding cryptographic signatures to ATProto records through two complementary patterns: inline attestations that embed signatures directly in records, and remote attestations that store proof in separate repository records. The specification prevents replay attacks through repository binding, uses CID-based content addressing for integrity, and provides the cryptographic foundation for verified credentials, trusted content, and authenticated interactions in the decentralized ATProtocol ecosystem.
The Arbiter - Group Management for Permissioned Spaces and Beyond - Zicklag's Leaflets
The permissioned data proposal has the concept of membership, but leaves it to the app to orchestrate it. The arbiter is our idea for a general-purpose, interoperable ATProto group membership service.
Three schemes for shared-private storage - Paul's Leaflets
Ente Photos: Store and share your photos with absolute privacy
Ente Photos is the private, secure photo storage app with end-to-end encryption. Cross-platform, open source, and self-hostable. Start with 10GB free.

ZKPROV: A Zero-Knowledge Approach to Dataset Provenance for Large Language Models
As large language models (LLMs) are used in sensitive fields, accurately verifying their computational provenance without disclosing their training datasets poses a significant challenge, particularly in regulated sectors such as healthcare, which have strict requirements for dataset use. Traditional approaches either incur substantial computational cost to fully verify the entire training process or leak unauthorized information to the verifier. Therefore, we introduce ZKPROV, a novel cryptographic framework allowing users to verify that the LLM's responses to their prompts are trained on datasets certified by the authorities that own them. Additionally, it ensures that the dataset's content is relevant to the users' queries without revealing sensitive information about the datasets or the model parameters. ZKPROV offers a unique balance between privacy and efficiency by binding training datasets, model parameters, and responses, while also attaching zero-knowledge proofs to the responses generated by the LLM to validate these claims. Our experimental results demonstrate sublinear scaling for generating and verifying these proofs, with end-to-end overhead under 3.3 seconds for models up to 8B parameters, presenting a practical solution for real-world applications. We also provide formal security guarantees, proving that our approach preserves dataset confidentiality while ensuring trustworthy dataset provenance.

The Atproto Spaces Alpha is Live - AT Protocol
Atproto Spaces, formerly known as “the permissioned data protocol,” is a new extension to atproto that enables non-public data. The alpha is now officially open. Here’s how to develop with it and what to expect as we work towards the full release.

The Atproto Spaces Alpha is Live - AT Protocol
Atproto Spaces, formerly known as “the permissioned data protocol,” is a new extension to atproto that enables non-public data. The alpha is now officially open. Here’s how to develop with it and what to expect as we work towards the full release.
