See, but this brings up an interesting point: What is JavaScript? The answer may surprise you: its the common parlance we very reasonably use to refer to the pr

See, but this brings up an interesting point: What is JavaScript? The answer may surprise you: its the common parlance we very reasonably use to refer to the programming language where we can do things like `"\t" == 0" and get `true`. But, interestingly: Oracle owns the trademark on that name, and so in very few if any formal specifications or standards bodies will you find the name "JavaScript"; its "ECMAScript". But, ok: Node advertises itself as a Javascript runtime, but the standards body against which they are tracking makes it an ECMAScript runtime; not more, not less. Probably not more, I'll grant you; but certainly less! You can pick any formally standardized version of ECMAScript, and find that Node.js has incomplete support, in some cases even for years after publication [1]. Again; its close enough nowadays, especially outside of ESNext which really doesn't count, that we're not talking about a useful or meaningful difference; but rather a pedantic difference. "Languages" formally specified independent of implementation are not languages. Language is the implementation; and the specification guides it. I'm not just talking about programming languages. I'm talking about spoken and written language as well. For lack of a better specification; The Oxford English Dictionary is not English. The dictionary is both more and less than english. It has a very large center-of-the-venn-diagram. But: commonly spoken English words will always exist for which it doesn't yet have definition for (it's as of yet blissfully unaware of "bussin" and "rizz"). Simultaneously; it will have words that make no sense to modern speakers, or definitions that have fallen out of use. It's the same situation with programming languages; the language is the implementation. The specification, if one exists, guides the implementation; but without absolutely no-more-no-less 100% coverage of the specification (which has not happened in NodeJS), and absolutely no-ambiguity-in-the-spec (which has never happened in any formal specification), they are meaningfully and inherently different. Because zero-ambiguity is impossible given fundamental constraints in politics, communication, and in a very real way physics: the specification isn't the language. Here's an interesting fun fact: TypeScript; that programming language we all love. It has no formal specification. Yup! People have been asking Microsoft since 2016, when they last published the specification, to update it, but the team has (explicitly or not, I don't know) taken the stance that the implementation (and its test cases) are the specification. The language is the implementation. So; what language is Deno-compatible code written in? The only accurate, formal, academic, correct answer is: Its written in Deno. The language is the implementation. Productively and usefully; its written in a language that is approximately similar enough to TypeScript that no one will notice. [1] https://node.green/ https://node.green/