Things im worried that I will never understand

https://trello.com/c/zPIVzgUg/477-confession-time-there-are-things-im-worried-that-i-will-never-understand

There are technologies which I'm worried that I will never understand. Let's admit that and then go through a few of them.

Description / Introduction

I would like to think that my technology preferences is based on objective reasons.

While trying to motivate some of my reasoning I noticed that my arguments were anything but objective. Instead I figured out that my reasoning is mostly fear/worry based, rather than objective. Let's talk about that, with a few different technologies as examples.

Understandability matters

Guessing or Debugging.

Sometimes I just type guesses and hope for the best.
Without any expected result.
... I hate when that happens.

This is not what I call "debugging".

Debugging is the process of coming up with a hypothesist and verifying it.

Maybe debugging.

Have you ever added logging you don't intend to keep, just to check whats going on?
Have you ever set an ugly background color in a CSS selector, just to check which elements change?

Probably guessing.

Have you ever commented out large blocks of code, just to check if a bug is there?
Do you have @Annotations you might not need?
Do you have CSS in your project which you are unsure if it's ever used?

Some things are very difficult. 17 years of research on Distributed Consensus. (Use something else if you can.)

Previous experience also matters

Mainly because you may already understand it.

Where does this come from?

"How did this end up here?"

CSS
- HTML - selector matching
Spring
- @Annotations
- "Externalized Configuration"
- "Profiles"
Spring + Maven
- Not all dependencies are downloaded before startup
Class hierarchies

Html + css example.

p {
  background-color: pink;
}
main p {
  background-color: black;
}
article p {
  background-color: green;
}
article > p {
  background-color: yellow;
}

https://developer.mozilla.org/en-US/docs/Web/CSS/Specificity

"Externalized configuration" example.

@Component
public class MyBean {

    @Value("${name}")
    private String name;

    // ...

}

https://docs.spring.io/spring-boot/docs/current/reference/html/features.html#features.external-config

"Profiles"

@Configuration(proxyBeanMethods = false)
@Profile("production")
public class ProductionConfiguration {

    // ...

}

// spring.profiles.active=dev,hsqldb

https://docs.spring.io/spring-boot/docs/current/reference/html/features.html#features.profiles

Unexpected dependency code.

cd ../docker-introduction/6_hello-world-http-java
code Dockerfile readme.md
cd -

No link, no explanation.

Constant vigilance required

Manual resource management
- Memory
- Sockets
- Files
null
Languages in languages
- json in yaml
- html in js
- go in python

"Helpful frameworks"

Vue (proxies)
Svelt (compilers) "Could we use the destiny operator in JS? Well no..."
React ("re-render everything")

Counter examples

SQL
- Horrible syntax, but mostly understandable.
ORMs (Object Relational Mappers)

Mental overload?

"Denial Of Service attack on your understandability."

npm

tree ../nodejs-typescript-openapi/node_modules/
code ../nodejs-typescript-openapi/package.json
code ../nodejs-typescript-openapi/package-lock.json

Maven

tree ~/.m2/repository/
code ../docker-introduction/6_hello-world-http-java/spring-petclinic/pom.xml
mvn --file ../docker-introduction/6_hello-world-http-java/spring-petclinic/pom.xml help:effective-pom
mvn --file ../docker-introduction/6_hello-world-http-java/spring-petclinic/pom.xml dependency:tree

pirfalt/things-i-fear