After I was contacted about the first steps, this was the process:

• 30-minute first screening: an interview with two developers to check you and know about your background.

• 3:10-hour Codility technical interview: 1 Java Puzzle, 1 Java Stream puzzle, 1 bug fix, and 1 SQL query creation.

• 1-hour meeting: After finishing the tech test, they asked to have this second technical interview where they asked me about what I did in the technical test. They asked some questions related to your last projects, of which you are really proud, and they went deep into it with some questions.

Tech tests:

• SQL - Joining question.
• Java Stream - Aggregator structure with some corner cases.
• Java Puzzle - K nails hammered into the same block of wood.
• Bug Fix - Recursion problem with N and K as input, but K was decreasing by 1 every time, and this was the problem.

I got more than 75% score in the tech test. I solved the bug-fix (something that they said almost nobody passes). I got 100% in the SQL question, but I did not get a good score in the Streams puzzle.

I didn't advance because I don't have enough SQL skills, as they said. For a Java role? You can see that you have a toxic environment.

What are your motivations to work at Adyen?

Why are you motivated to come to the Netherlands?

They are going to ask why you used a certain data structure to solve the puzzle.

How can we improve SQL queries in the database?

Do you know why the "Stream Closed" error happened in your solution code?

Do you know how streams work?

Why use a for-each loop instead of streams?

If you were to write code that would remain for 10 years, would you write it using Java Streams or JDK internals with a simple for-each loop?