!rant
TL;DR: Can anyone recommend or point at any resources which deal with best practices and software design for non-beginners?

I started out as a self-taught programmer 7 years ago when I was 15, now I'm computer science student at a university.
I'd consider myself pretty experienced when it comes to designing software as I already made lots of projects, from small things which can be done in a week, to a project which i worked on for more than a year. I don't have any problems with coming up with concepts for complex things. To give you an example I recently wrote a cache system for an android app I'm working on in my free time which can cache everything from REST responses to images on persistent storage combined with a memcache for even faster access to often accessed stuff all in a heavily multithreaded environment. I'd consider the system as solid. It uses a request pattern where everthing which needs to be done is represented by a CacheTask object which can be commited and all responses are packed into CacheResponse objects.

Now that you know what i mean by "non-beginner" lets get on to the problem:

In the last weeks I developed the feeling that I need to learn more. I need to learn more about designing and creating solid systems. The design phase is the most important part during development and I want to get it right for a lot bigger systems.
I already read a lot how other big systems are designed (android activity system and other things with the same scope) but I feel like I need to read something which deals with these things in a more general way.

Do you guys have any recommended readings on software design and best practices?

!rant

Got back into android development recently and while everything was pretty flawless ( I managed to get the basic concepts implemented in a day) something wasn't right.

For some reason I was not happy with the code i wrote, although I took examples from google and tried to adapt their code style. It looked aweful. I hated my code.
But the code itself wasn't the core of the problem. I could easily add new features and replace components with new implementations without breaking the app. All those "good code quality" identifiers were there.

Turn out the problem is Java. Or to be more specific: Java 1.6
Every listener which only calls a single function once a worker has finished needs 6 lines of code. If you implement the inferface in the class it gets messy once there are multiple workers and you have a generic interface. And there are no lambdas!

So I made the switch to Kotlin.
The app was converted to kotlin in 30 Minutes​. Android studio can convert the classes automatically and very little manual work is needed afterwards.
After that I spent 2 hours replacing the old java concepts with Kotlin concepts: lamdas, non-nullable types, getters and setters in kotlin style (which in this case is c# style) and some other great thing.
The code is good looking now. I like it. I like kotlin as it has a lot of cool things.
Its super easy to learn. It took me about 2 hours to get into it. It combines concepts from java, javascript, c# and maybe a few other languages to form a modern jvm 1.6 compatible typesafe language.

Android dev is fun again!

So I recently had a university project which focuses video game audio. We had to work in groups of 3 students and the task was to create a video game which uses audio as a gameplay mechanic.

Our idea was to create a game where you collect different audio samples which get looped as background music, and you have to select the correct ones to have a nice tune. To make it a bit more challenging we had enemies, guns and grenades plus doors which only open if the correct music is playing.

The guns fire on-beat, and the grenades always explode on the first beat of the next bar.
It was quite challenging to get things synced since even small offsets are noticable.

I wrote some nice code and theoretically it should have worked but for some reason the gun shots and the grenades didn't quite hit the beat of the music.

I tweaked stuff, created workarounds, optimized lot's of code to get execution times down but it still only worked sometimes.

I tweaked more and more only to realize that the timing drifted over time.

At that time I worked 20-30 hours on tweaking and trying to get it perfectly timed.

After recalculating some numbers I realized that all the audio samples are recorded at 135 bpm, but the guys who did the recordings said it was 130bpm.

I asked them if it could be the case that the samples are 135bpm and they said:
"yes, they are at 135 bpm as we told you"

I scrolled back in the telegram conversation only to see that they said 130.
Changing the number to 135 resolved all the problems and all of my workarounds and tweaks weren't needed.

So I worked for nearly 30 hours just because they didn't notice their fault and even when they realized that the timing is off sometimes (which took forever because they never played the game), they didn't even consider that they might have given me the wrong numbers.

This all wouldn't be that bad if both of my teammates had worked for more than 15 hours but they didn't. I did all the hard work and the only single thing they did fucked up my workflow. It fucked up the system I created and it fucked up the gameplay as things got unpredictable. Because of their fucking fault I worked as much as both of them combined IN ADDITION to all the other work I did (built 3 maps, coded everything, created animations, ...)

I love working in teams, but only if the whole team is motivated. Those two fuckers were the exact opposite.
Luckily i found the error so I could fix it, but guess with whom I'll never ever work together again?

God damn...if you want to be a developer learn using git and fucking STOP messing up the repo every time you push something.

Understand the importance of branches and use 'em so the problems you're causing are isolated and stop commiting / pushing on master....ITS NOT THAT HARD TO READ THE FUCKING CONTRIBUTION GUIDELINES!!!

Alright then...

At least it parsed null as a string. Better than crashing, but the correct url would have been slightly better.

Attending in a local game jam with some friends.
One of the team members wrote the worst code I've ever seen. After him realizing that it's buggy as hell he left to sleep having me fixing his mess at 4 am to somehow get something done by the end of the event.
It resulted in me rewriting nearly everything he had done.

Guess which team didn't manage to have something playable in the end...