Slack's desktop client gets major performance improvements after codebase rewrite

Slack said its desktop and web client now launches 33% faster and uses 50% less memory.
Written by Natalie Gagliordi, Contributor

Slack announced on Monday a major performance update to its desktop and web client. The workplace collaboration player said the code for its desktop client -- its oldest piece of codebase -- has been rewritten from scratch, resulting in faster start-up times, more efficient memory usage, and overall improved user experience. 

According to Slack, its desktop app now launches 33% faster and uses 50% less memory. Meantime, users can join calls in Slack up to 10 times faster compared to the legacy desktop client. 

The new desktop app also aims to address connectivity issues. Slack said the new version lets users run Slack and view previously opened channels and conversations even if their signal drops in and out. 

Slack -- which now has over 95,000 paid customers and more than 10 million daily active users -- said it has been rolling out updates stemming from this new codebase for nearly two years. The first modern piece of the Slack app was its emoji picker, followed by the channel sidebar, message pane, and "dozens" of other features.

"This new version of Slack has been a long time coming, and it features the contributions of dozens of people who have been working through the last two years to roll it out seamlessly to customers," Slack said in an engineering blog post. "The key to its success is the incremental release strategy that we adopted early on in the project: as code was modernized and features were rebuilt, we released them to our customers. Conventional wisdom states that rewrites are best avoided, but sometimes, the benefits are too great to ignore."

Slack said the update would roll out gradually over the next few weeks. Users will receive an in-app notification when they're running the latest version.


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