mimecast

DTail is a distributed DevOps tool for tailing, grepping, catting logs and other text files on many remote machines at once.

Java implementation library for RFC 8461 - SMTP MTA Strict Transport Security.

Debug and development tool for MTA architects! Robin is a highly configurable SMTP client for testing and debugging SMTP servers.

I/O Riot is a tool for logging, replaying, and benchmarking I/O on Linux