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      </svg></a> </h2>
<section aria-labelledby="toc_why-do-i-need-tests">
<p>Writing tests is a necessary ingredient if you want to guarantee users and stakeholders that your app, whether small or large, will function as intended at any given time. The larger your app, the more costly and error-prone manual testing becomes.</p>
<p>Writing tests is also a fun activity, a nice change of pace from delivering features daily, and a way to help you refactor code a