Trust center
Verified, evidential, and documented
Whether you need a standard rollout, private infrastructure, or stricter residency and isolation requirements, Letro gives you a verified, evidential foundation for secure client communication.
What we publish
7 documents
01+Security overviewLetro is built as a Proof-of-Service / Digital Registered Delivery platform.
02+Encryption modelMatrix end-to-end encryption with Olm/Megolm, TLS 1.3 transport, device verification, and what the homeserver can and cannot see.
03+Encryption & auditabilityLetro is encrypted and evidential. Here is how those two properties fit together.
04+Data residency & infrastructureWhere Letro data lives, who operates it, and how each deployment tier changes the answer.
05+Incident response outlineHow Letro detects, contains and resolves security incidents, and how customers are notified.
06+Subprocessors listThe third parties that process data for the Letro platform, website and sales process: who they are, what they handle, where, and under which safeguard.
07+Vulnerability disclosure policyHow to report a security vulnerability in letro.com or the Letro applications, and what you can expect from us.
LetroSeptember 2026
Independent penetration test
An independent penetration test of Letro by ImmuniWeb is underway (September 2026). The report will be available to customers under NDA once the engagement is complete.
Assessor: ImmuniWebRequest access
Discuss Your Deployment Model
Whether you need a standard rollout, private infrastructure, or stricter residency and isolation requirements, Letro gives you a verified, evidential foundation for secure client communication.
