What is closed source ? Aren't those up to date?

https://github.com/joinloops/loops-server#license

Loops Server is open-sourced software licensed under the AGPL license.

That's misleading, they plan on being open sourced according to pubs:

Similar to how Mastodon offers an open source, distributed version of X, the fediverse is getting its own TikTok competitor. This week, an app called Loops began accepting signups on its new platform for sharing short, looping videos. Still in the early stages, Loops is not yet open sourced, nor has it completed its integration with ActivityPub, the protocol that powers Mastodon, Pixelfed, PeerTube, and other federated apps.

However, both those efforts are in the works and when complete, will allow Loops to add another layer of social activity to the growing open social web known as the fediverse, which now has north of 11.6 million users and over 1 million monthly active users. (Mastodon accounts for roughly 65% of that activity.) Growth in this space has also encouraged other apps to adopt ActivityPub, like social magazine app Flipboard and Meta’s Threads. The latter is not yet fully integrated but already has more than 200 million monthly active users.

https://techcrunch.com/2024/10/25/the-fediverse-is-getting-its-own-tiktok-competitor-called-loops/