https://steamcommunity.com/games/505230/announcements/detail/3652908044150019722

Hope it gets here soon!

I hope that the patch will appear on GOG in the near future, according to rumors, the game's performance has really increased several times with this patch.

*короче говоря - жду с нетерпением

My copy of the game got updated today.

I don't see it yet. Did you get the update via Gog Galaxy?

Yes, it auto-updated, although I can't see the new changelog. Could be that I'm mistaken, and it's an earlier patch. My version is currently 1.5.29823-REL-DEV-ST.

Ah, so it is the newest update. The offline installers are still at 1.4

Here the changelog if you haven't seen it yet:

1. Optimization improved in many respects, most noticeably:

lowered the amount of RAM used;
lowered freeze frequency;
improved average FPS;
lowered CPU usage.

2. Headshots added!
3. Gamepad support added.
4. Game logic polished, fixed a number of smaller bugs.

The regular installer version has been updated. The game runs much more smoothly now.

You'll probably want to start a new game after installing it, however. Loading an old save with the newest update resulted in poor performance, while the same scene ran smoothly after starting a new game.

I noticed the same issue. Thanks for the tip!