The project concerns the critical infrastructure and Open Source components that comprise "Let’s Encrypt", an automated certificate authority that is free to use and built on Open Source components. The services provided under this project cover in several milestones among other things the targeted analysis and technical improvement of the service’s infrastructure and its software components for post-quantum cryptography (PQC) protocols and techniques as well as applying testing mechanisms to ensure it‘s correct and performant running to especially support the security and trustworthiness of communication in the public interest.