Programming challenge websites

To maintain my limited Elixir programming skills, I use coding challenge websites such as Hackerrank, Codewars, and, more recently, Exercism. The sites offer puzzles that can be solved in different coding languages. The websites have a decent online editor so you can get right into coding.

While the exercises certainly aid me in keeping up rudimentary skills in Elixir, the tasks are mostly brain teasers, which require minimal coding. Unfortunately, it is difficult to find any exercises which are about the issues I face in my daily work — things as manipulating complex data structures, mapping them to new ones, and so on.

Practicing programming like this has the same issues as using these kinds of puzzles as interview questions. Interviewee with a decade of experience is demeaned and humiliated by a seemingly simple task under the stressful circumstances. I have seen this over and over again when giving interviews, and nowadays, I am firmly against live coding.

One of the better exercises I recently solved was to simulate a bank account. No complex arithmetic is needed. You can focus on writing code, which addresses the issue elegantly with clearly defined data structures, which is the essential thing in the daily job as a coder.

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