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Listen "zkPDF and zkID with Vikas Rushi and Ying Tong"
Episode Synopsis
In this episode, Anna Rose and Kobi Gurkan chat with Vikas Rushi from PSE, and Ying Tong to explore two topics at the intersection of ZK and the real-world data: zkPDF and zkID.
First they dive into zkPDF, a set of tools for proving facts on digitally signed PDFs. Vikas talks about the challenges of parsing data inside zkVMs—working with decades-old specifications that use many different encodings, and tackling practical use-cases like bank statements and ID verification. They also explain how issuers, such as India’s DigiLocker, can generate proofs in a way that protects individual privacy.
Next they cover zkID and the EF’s work on building a system that would meet the EU’s Digital Identity Framework requirements ahead of its 2026 rollout. Ying Tong explains how the EF’s work on zkID differs from existing zk-based identity projects, particularly through its device-binding requirements, the cryptographic community’s feedback to the EU Commission, the trade-offs between proof systems, PSE’s work on standards and more.
They wrap up with a chat about the challenges of revocation in both systems, and what’s next for the projects.
Related links:
Episode 367: Local-First with grjte and Goblin Oats
Episode 366: Bringing ID Onchain with Self
Episode 363: Bringing ZK to Google Wallet with Abhi and Matteo
Episode 362: zkTLS with Maddy from Reclaim
Episode 358: Building ZK Registries Onchain with Rarimo
Episode 353: Making ZK More Human with ZK Email
Episode 330: Frameworks for Programmable Privacy with Ying Tong and Bryan Gillespie
Community Privacy Residency
Anon Aadhaar
DigiLocker
First they dive into zkPDF, a set of tools for proving facts on digitally signed PDFs. Vikas talks about the challenges of parsing data inside zkVMs—working with decades-old specifications that use many different encodings, and tackling practical use-cases like bank statements and ID verification. They also explain how issuers, such as India’s DigiLocker, can generate proofs in a way that protects individual privacy.
Next they cover zkID and the EF’s work on building a system that would meet the EU’s Digital Identity Framework requirements ahead of its 2026 rollout. Ying Tong explains how the EF’s work on zkID differs from existing zk-based identity projects, particularly through its device-binding requirements, the cryptographic community’s feedback to the EU Commission, the trade-offs between proof systems, PSE’s work on standards and more.
They wrap up with a chat about the challenges of revocation in both systems, and what’s next for the projects.
Related links:
Episode 367: Local-First with grjte and Goblin Oats
Episode 366: Bringing ID Onchain with Self
Episode 363: Bringing ZK to Google Wallet with Abhi and Matteo
Episode 362: zkTLS with Maddy from Reclaim
Episode 358: Building ZK Registries Onchain with Rarimo
Episode 353: Making ZK More Human with ZK Email
Episode 330: Frameworks for Programmable Privacy with Ying Tong and Bryan Gillespie
Community Privacy Residency
Anon Aadhaar
DigiLocker
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