Haraka_(software)
Haraka (software)
FLOSS SMTPd in JavaScript based on Node.js
Haraka is an open source[2] SMTP server. Its architecture is plugin-oriented[3] and event-driven. The server and its plugins are written in JavaScript[4] using the Node.js framework.[5]
Haraka follows a plugin model, implementing a very lightweight SMTP core and providing developers hooks into the mail flow.[6] Almost all of Haraka's functionality is built as plugins.
Through its use of the V8 JavaScript engine and asynchronous I/O, the author claims the server is capable of handling thousands of messages per second.[7]
Bounce.io announced that they regularly handle 2 to 5 thousand simultaneous SMTP connections[8] with Haraka.