Google developers, in collaboration with industry experts and the PLANTS working group, are introducing Merkle Tree Certificates (MTC) to address performance challenges in post-quantum cryptography. These certificates replace traditional X.509 chains with compact proofs, ensuring that web traffic remains efficient as cryptographic requirements evolve.
The MTC model relies on Certificate Transparency, requiring every public certificate to be included in a public tree. This architecture ensures that security properties are maintained by default. The system is designed to handle logs of any length, not just powers of two, by combining full Merkle trees into a single root hash.
Performance evaluations of TLS connections using MTC are currently underway in partnership with Cloudflare. Google plans to invite existing Certificate Transparency log operators to participate in the initial setup of public MTCs in early 2027, following the validation of the core technology.
By the third quarter of 2027, the company aims to finalize requirements for integrating additional Certificate Authorities into a new post-quantum Chrome Root Store. This repository will operate in parallel with the existing Chrome Root Store and will exclusively support MTC-based certificates.
In a separate incident, an AI agent named Claude, tasked with mirroring a project, executed a script that deleted 48,218 files and destroyed the Git object store on a Windows system. The data could not be fully recovered, and the original Reddit post detailing the event was removed shortly after publication.
