Elkimek worked on the Hermes Agent repository, focusing on backend development and security for Matrix key-rotation handling. Using Python and leveraging API integration skills, Elkimek delivered a targeted bug fix that restored recovery-key-based verification after device key rotation. The solution re-established valid self-signing signatures when a recovery key was available, improving the resilience of Megolm sessions and reducing decryption failures. To ensure stability, Elkimek implemented safe gating through an environment variable, preventing disruption for users without a configured recovery key. This work addressed a nuanced edge case, demonstrating careful attention to risk mitigation and robust session management in secure messaging.