Open source just means the source code is available. It doesn't mean you can legally use it. That is, in fact, the whole point behind the most famous open source license, GPLv3: code is open source, but there are still restrictions on how you can use the code. I don't know about now (most projects I work on are MIT-licensed, these days), but there was rancor around the move from v2 to v3 because v3 was more restrictive.

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bramhaag 4 days ago | parent | next [-]

'source available' means the source code is available. Open source comes with a whole set of guarantees [1] about free redistribution and derived works.

Copyleft licenses like the GPL come with extra guarantees that do not violate the core guarantees of open source software. Instead, they make them stronger. The 'restrictions' GPL imposes essentially boil down to this: "if you use (parts of) GPL software, you must give your users the same freedoms the GPL guarantees." GPLv3 and AGPL closed up loopholes that allowed people to bypass those clauses.

[1] https://opensource.org/osd

	▲	KPGv2 2 days ago \| parent [-]
		Your link is to a politicized advocacy group, the OSI. Are you above, say, forty years old? You should remember, then, the arguments over introducing "libre" as a term because "open source" didn't describe those free redistribution rights.

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thayne 4 days ago | parent | prev [-]

Even if it was licensed under GPL, which it isn't, forking the project to create another open source project is allowed, as long as the fork is also GPL licensed.

But in this case the original project used the MIT license, so the only requirement is that it the form includes attribution to the original project.