Mark KaplunWhat is calmPress?
Basically, it is WordPress version 4.9, the last version before Gutenberg became core in version 5.0

Created by Mark Kaplun, who is currently the sole developer, it does not use the Gutenberg block editor and sticks with the classic TinyMCE editor.

As he says on his site, he didn’t start calmPress purely because of the Gutenberg issue. He saw there were a lot of things wrong with what WordPress had become, and the release of WP 5.0 was merely an opportune time to make a fork and refine it to operate leaner and cleaner.

Some people at WordPress are supportive of what calmPress is trying to achieve, but others are angry at what they see as an unnecessary and disruptive move. WP users who want nothing to do with Gutenberg are simply happy there is an alternative that works the way they’re used to.

Is calmPress a viable long-term option?
Mark’s aim is to create a more stable and calm experience for all of its users; whether they are authors, admins, designers or developers, by taking into account the lessons learned over time and recognizing the requirements of modern sites.

He wants to focus on security and reducing bloat from the core files. Functions that have stayed in WordPress for years, but no longer serve any useful purpose, will be removed from the core. His approach is more aggressive than say that of ClassicPress.

Currently there are two versions available, a Beta and an Alpha. The Beta version, 0.9.x is virtually the same as WP 4.9.x and is suitable for live sites. The Alpha version, 1.0.x is the more aggressive one, and is currently only suitable for test sites.

I have installed both on two test sites. The Alpha version is where you can see how Mark is starting to remove the bloat and unnecessary features with each point update.