Suggestion: switch to MIT-0 license instead of MIT license

[skissane]

I notice you have this licensed under both the Unlicense and the MIT license. I know you originally had it just under the Unlicense, but you added MIT license as an option in 9adf4e0 due to objections from some people that public domain dedications in general (and the Unlicense more specifically) were not legally valid in some countries (Germany is commonly cited in these discussions)

However, if you are looking for a copyright license which is close as possible to the Unlicense, that would be the MIT No Attribution License aka MIT-0. The Unlicense lets people use the software completely unconditionally, without even requiring attribution. By contrast, MIT imposes a legal duty to include an attribution notice in all copies of the software, source or binary. So, you are offering a choice of licensing terms, but the second (in requiring attribution) is stricter than the first. Whereas, if you switched to MIT-0 – which is just MIT with the attribution clause deleted – your two licenses would be essentially identical in what they let people do, they'd just differ in wording. And, I've never heard anyone object to MIT-0 on legal grounds – given how (intentionally) similar it is to MIT, it would be difficult to argue that MIT-0 has legal problems without arguing that MIT has them too. So, maybe you might want to think about whether you should make the switch.

On the topic of attribution: of course it is the polite and ethical thing to do, but not everyone agrees with turning a matter of politeness and ethics into a formal legal obligation. That can create pedantic debates about whether one has complied with the bureaucratic letter of it, and in large projects which might use dozens of open source libraries, potentially with many subtly different attribution requirements, attempts at pedantic compliance can result in a lot of busywork.