Bevy, specifically because it is an ecosystem of libraries. I tried UE3/4, Unity and Godot, and I've always found the complexity of tooling and amounts of options available completely overwhelming. Not to mention, that most of these tools and options funnel the developer into very specific and opinionated ways of doing things.
By contrast, Bevy is just a Rust crate, and it is modular - I can connect only those plugins and functions I really need. If I am ever confused by some function, or a type, I just press "gd" and my nvim will show the definition of this function or type - it feels refreshingly simple and seamless in comparison with the enormity and complexity of Unreal or Unity. At any point in time I am staring at my code, I only see things that are relevant to the problem, and nothing else.
I can bring my own tooling (editors, analysis tools, asset pipelines etc.), projects are easy to build and automate, - it is pure bliss.
The absence of an editor allows me to hook up whatever I want: LDTK, Trenchbroom, even Unity could be used as a scene editor. There is virtually no vendor lock-in with dependencies either. Don't like Rapier as your physics engine - easy-peasy, you can use Avian, or something else, or something custom, or nothing at all. Don't like Bevy UI - no worries, there is Egui, multiple integrations with other UI frameworks, you can even use Typst layouts for your menus if you so desire.
Right now I am working on a literate game with a friend: our sources are markdown files with bits of code in them. Our automation compiles markdown to Rust sources and then builds the game, potentially along with the devlogs and some other auxiliary artifacts.
My non-technical partner contributes to the repo freely, treating it as an Obsidian vault, - in our team there is no distinction between technical writing and development, our game design document and source code are literally the same thing. This approach has removed loads of roadblocks and allows us to safely and controllably accumulate knowledge, before distilling it into a working game.
It wasn't trivial to set up, but it wasn't overly complicated either - good luck replicating this set up with Unity or Unreal though.
I have for a bit, decided to stick to MD because of its accessibility to my non-tech collaborators, it is easier for them to install Obsidian, and MD is very well-known.
Aside from that, I am planning to use Pandoc to process my sources into other deliverables: web pages, PDFs etc. I am myself still learning this ecosystem, and markdown (in my experience) just enjoys more visibility.
Truth be told, I did not have any exposure to Org Mode prior to looking it up for knowledge management, so all of the above might be my "little duck" brain speaking.
1.2 Mb of uncommented code using single letters for variables written 30 years ago that somehow compiled into ASCII based vertical scrolling space shooter.
Yes, I'm embarrassed; No, you can't play it.
I still have the floppy disk, but I refuse to buy a drive to load the file onto my current computer because I would cringe so hard I would die. It was written in god-damned QuickBASIC...
PICO-8, though it's more of an on-and-off again project of trying to teach myself to program again.
But I like the limitations you have to work with, and even I can create some crude 8x8 sprites :)
I haven't found one that's good enough that i can say it's a favorite. I think it's usually best to seek out an engine for each project because they all have major upsides and major downsides that can make or break a project.