Unified Grid: How We Re-Architected Slack for our Largest Customers

Slack’s enterprise solution allows users to join multiple workspaces within the same organization. However, for years, users could only view channels, messages, and other content from a single workspace at a time. For instance, a user could join workspaces focused on engineering and design, but they could not view messages from both workspaces in a single place. This forced users to frequently switch between workspaces to do their jobs, disrupting their concentration. It was also inefficient from a performance standpoint, with client applications fetching and storing redundant data which was unchanged across multiple workspaces.

While much work was done to improve the experience for users in many workspaces, we believed a different approach was necessary to truly fix the user experience and performance issues caused by the workspace-centric model. So we took a step back and asked: what if users could see all the content they can access—channels, messages, etc—across all their workspaces in a single view? With this, the Unified Grid project was born.

This talk will tell the story of Unified Grid, an ambitious project that re-oriented Slack's architecture around the user and organization, instead of the workspace. We will explore the technical challenges that convinced us a re-architecture was necessary and continue on to how we evolved Unified Grid from a barely-functional prototype to a top company priority. Along the way, we’ll learn some lessons about how and why you might re-architect large software applications.