Their desktop apps are built with Electron AKA Atom shell. Slack is built on PHP, using MySQL as the database, Smarty templating for the view side of things and everything is hosted on Ubuntu servers. They help verify that the data remains intact and stored safely at all times.

Is Slack using MySQL?

Slack operated MySQL servers in an active-active configuration. ... Availability, performance, and scalability in our datastore layer is critical for Slack. As an example, every message sent in Slack is persisted before it's sent across the real-time websocket stack and shown to other members of the channel.

Is Slack run on AWS?

Slack and AWS share a commitment to enhancing workforce collaboration. ... By integrating AWS services with Slack's channel-based messaging platform, we're helping teams easily and seamlessly manage their cloud infrastructure projects and launch cloud-based services without ever leaving Slack.”