During June 2025, Radek Zikmund focused on security hardening within the files-community/Satori repository, addressing a critical aspect of SMTP email delivery. He implemented a targeted fix in C# to enforce TLS negotiation, ensuring that the HELO command is not used when TLS is required and that an SmtpException is thrown if the server does not support STARTTLS. This approach improved the reliability and security of outbound email transmissions by aligning with modern encryption policies. Radek’s work demonstrated expertise in email protocols, network programming, and TLS/SSL, delivering a robust solution that reduced the risk of unencrypted SMTP communications.