New languages and virtual machines are proposed at an alarming rate, followed by new versions of them every few weeks, together with programs in these languages that are responsible for actions of potentially significant value. Many bugs and exploits, for example in the new cryptocurrency space, are due to flaws or weaknesses of the underlying programming languages or virtual machines. Formal analysis and verification tools are therefore needed immediately for such languages and virtual machines. The usual post-mortem approach to formal language semantics and verification, where the language is firstly implemented and used in production for many years before a need for formal semantics and verification tools naturally arises, simply does not work anymore. We present recent academic and commercial results in developing languages and virtual machines that come directly equipped with formal analysis and verification tools. The main idea is to generate all these automatically, correct-by-construction from a formal specification in the K Framework. We will also give a demo of the K framework by means of a simple language.