Ship of Theseus paradox for developers
<p>Suppose you are employed as a software developer. You work in a business where you code a lot of components. During this period, you also work as a freelancer to earn extra cash.</p>
<p>These freelance jobs may require some of the same code as you write for your day job.</p>
<p>The question: When are you allowed to reuse code that you wrote for (and is therefore owned by) your employer?</p>
<p>I think the <a href="https://en.wikipedia.org/wiki/Ship_of_Theseus" rel="nofollow noreferrer">Ship of Theseus</a> paradox has some relation to this.</p>
<blockquote>
<p>The ship of Theseus, also known as Theseus' paradox, is a thought experiment that raises the question of whether an object that has had all of its components replaced remains fundamentally the same object. The paradox is most notably recorded by Plutarch in Life of Theseus from the late first century. Plutarch asked whether a ship that had been restored by replacing every single wooden part remained the same ship.</p>
</blockquote>

<p>It really comes down to the licensing of the code, the context of what you built, how you built it and when something is built.</p>
<p>Think about it like this. If you used your previous jobs resources (like a company laptop). Then they can claim anything produced on that laptop belongs to them.</p>
<p>If you built something on company time but used your own resources. It may also belong to them if they were paying you during those hours.</p>
<p>If you used an open source library like Next.js to build a custom application for job1. Your job1 doesn't own the Next.js library. You can switch to job2 and still build on top of that library. However, use of any of the customized application code built from or for job1, might open the door for claims against what ever you are building for job2.</p>
<p><strong>Open Source</strong></p>
<p>Your best approach to avoiding legal issues across jobs is to open source any of the code you plan to reuse and implement a <a href="https://snyk.io/learn/open-source-licenses/" rel="nofollow noreferrer">code license</a> that allows you to use, modify, or distribute software code freely.</p>

<p>The code you write as an employee belongs to your employer in most normal circumstances. It isn’t yours it’s theirs.</p>
<p>Without permission you have no right to do anything with it outside work.</p>

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