Edit: 3/13/2025. Changing from 5 stars to 1. Noysi shut down again, no warning and no way to contact the owner, Hector. Given the past context, it is unlikely Noysi will come back, meaning all LTD holders lost their money. Relatingly, AppSumo has also elected to drag its feet on credit reimbursements.

—Original review—
I am a very longtime user of Noysi, and I find the product one of the best tools ever sold on AppSumo. You want a secure alternative to Slack? This is it.

Now does it have everything that Slack has? No. Does it have areas to improve? Sure. But do you want the ability to invite all your people across all your businesses into your own controlled chat system with unlimited data storage? That’s right— UNLIMITED DATA STORAGE. It’s great.

In the years I’ve had Noysi, it did indeed go down for a few days on February 2025. As of today, 13 FEB 2025, it is back up. I will admit that it was sudden, out of the blue, and a bit disconcerting, especially if the claim of financial strain is true. But I cannot imagine all these extremely negative reviews over the last few days are fair or even genuine.

This is a good product. No, a great product. We need to keep it alive, because it is extremely useful to virtually anyone in any vertical.