... Not everyone needs external tools to ensure quality in their code... but, I work on things from time to time that have absolutely no tests. No unit tests, no functional tests, no browser tests, no code quality analysis. Needless to say, some of those things make me want to tear my eyes out. Frankly, though, when a project hits success, there is rarely time to go back and ensure quality of old code - instead, we find ourselves merely bolting on new things. Writing software does not have to be this way.

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