I'm convinced that playing the piano has allowed me to type faster and commit keyboard shortcuts to muscle memory faster too. While coding isn't about typing quickly, there's a whole bunch of times when I've had an idea, and had to get that down into code as quickly as possible before I forget it - and that's when I really find fast keyboard work comes into its own.

WK289 Playing automation games like factorio, heavily modded Minecraft, satisfactory, etc, let's me do all the things that I want to do in my job but we simply don't have the time or resources for. It makes me a better engineer because I'm less frustrated during my day job.

Music. Music teaches you numbers, creativity, patterns, structure, and basically primes your brain for math and creativity in that space. In addition, it teaches you how to think both within a structure and outside the box, as well as the importance of repetition, memorization, and learning a new language.

Music really was my second language, and the ability to read/write it fluently is a skill that takes a long time to master. I really believe that it increases your brain plasticity so much.

Judo.

I might sound like one of those wierdos that are overly into Japan, Martial Arts and such, but I really enjoy Judo.

It is a sport where you have to FEEL the contact with your opponent.
Practising Judo made my day-to-day stress go away in just about 20m and also kept me in good shape, made me meet a lot of people/friends, lead me to live in a certain way and interact with people in a certain way (a good way, actually).

It also taught me which parts of the body are the most dangerous/fragile and cause the most pain.

Knitting. It's absurd how technical a skill it is, and I definitely didn't realise that when I learned it!

Running hands down.

Non tech hobbies that helped me with developement:

Lego technic/mecano/knex were a great way to learn about abstraction, you build modules that you can reuse somewhere else.

Cooking is similar, you notice useful patterns that you can reproduce. E.g. roux, which is butter and flour is used for a lot of sauces, then add milk and you get béchamel, which is again used for a lot of sauces.

Coffee brewing helps because I can't focus if I don't get coffee.

Drinking Fireball and wanking.

I'm pretty sure I'm not the only one that will say gaming.
Because of gaming I've been in contact with computers a lot and learned a bunch of things that would become useful as the base for learning coding.
Things as simple as using and abusing the file system, file locking and files principles, Googling stuff, etc.

Play designer board games; they are multi-tenant programs, complex algorithms, modularity, meticulously balanced, and all elegantly linked to an artful UI. They are also made out of cardboard.

It is hard to play them and not become a developer that builds increasingly holistically.

Non tech hobby of mine: bird watching (you may have guessed based on my username). Although it’s a non tech hobby, there are so many great apps to help identify birds and learn about them. EBird, birdnet, Merlin, picture bird etc. I also have a few books about bird watching.

Crazy how many different kinds of birds you can see when you really start paying attention.

Old-school tabletop RPG and board games.
Taught me how to work out data and stats tables, establish many-actors processes and strategies, how to ask for clarification (and give it), and even gave me practice in drawing a representation of what is in my mind, and understanding someone else's.
Who have ever surrounded a dragon in D&D knows what I'm talking about.

Approximating my personal ballmer peak

Cooking.

Made me better at explaining processes, multithreading and writing clear recipes.

Having sex. Or long hot showers. It's amazing how doing either of those helps me unplug for the day and start to refresh my self for the next day of coding.

Context, I used to burnout quiet often. Learning to unplug allowed me to be a better software engineer that could work better over an extended period of time.

i think most of my interests/hobbies end up being useful at some point at work, that's why i usually try out a lot of different things. i think two major ones have been language and design, there are concepts in both that help a lot in coding. I've been particularly interested in semiotics, which is a total trip, but it's very worth looking into for any type of science.

My current work...
3 years of formation...
3 years of experience...
And I didn't know the basics to operate the machines used here.
Also I'm only getting minimum wage and I'm a temp so fuck it. I already knew to much for what I'm paid.
Also...
Extra formation for the next job :p

Reading books. When you are used to focus on long texts, those sw related books are not scary anymore. I can finish reference material easily if it keeps my attention.

Lifting

Make sleep far easier so I feel rested and I can code better

Any non-tech hobby usually helps my coding, because relaxing breaks are far more efficient if I'm not just laying in a bean bag trying not to think about work but rather engaged in something unrelated. During the summer I was storing a really good electric guitar because the owner emigrated, so when I felt stuck I played some music. I used to play the cello in middle school but I was never really good at it nor did I care to practice properly because it felt a lot like yet another class to attend. Apparently music practice works whether you do it in one long or several short rounds as long as the total time is enough.

Building gunpla.

Helped me postponing my burnout by doing 1 page a day everyday at lunch break (or 2 steps, depending on the model)

Also helped a lot with realising its fine to break and customise stuff, that most hardware is just marketing & that the right tool, while being cheap, can save you a huge headache and lead to a better result.

Reading... About coding? And the horrors when monkeys code?