Ana Cazarotto developed a configurable SMTP sender limit for the zotonic/zotonic repository, focusing on enhancing email delivery reliability and performance. She introduced a new configuration parameter that allows operators to set the maximum number of simultaneous SMTP senders, updating the backend logic to dynamically read this value from configuration files. Working exclusively with Erlang and applying backend development expertise, Ana’s solution enables more predictable email throughput under varying loads and simplifies operational tuning across different environments. The work demonstrated careful configuration-driven development and disciplined version control, addressing issue #4308 and reducing the risk of SMTP bottlenecks without introducing new bugs.