Mattermost: Self-Hosted Slack Alternative with Corey Hulen

Software companies today rely on group chat applications.

The world of startups and small businesses is dominated by Slack. But for some large enterprises, regulatory constraints prevent them from using Slack. Slack is a web application that is hosted in the cloud, and regulated industries such as banking often need to run their applications on their own on-prem infrastructure.

Mattermost is an open source alternative to Slack that can be self-hosted. This means that all of the networking complexities and scalability challenges that are controlled in the cloud by Slack need to be handled by open source code rather than managed services running in the cloud.

Because it is open source, Mattermost can also be redesigned and customized. Uber designed their own custom version of Mattermost called uChat.

Corey Hulen is a co-founder and the CTO of Mattermost. He joins the show to discuss the motivation for building Mattermost and the engineering challenges of building an open source chat system.

For more episodes about building chat systems, we’ve done several shows about Slack, covering the engineering, security, and chat system.


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