I am a big advocate of version control and testing for your software. The main reason is that modern systems are incredibly complex, and capturing what has been done (and what is happening), along with looking for potential issues, is important. It might be critical for ensuring you have success in building software.

Part of the reason is this post on software complexity. Now I don't think the complexity is killing software developers. I do think it adds to developers' stress, and in poorly managed environments, the complexity makes for a poor job experience for many.  While I do think most people are smart, and they find ways to overcome this, they just don't enjoy the process.

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