YJIT: Building a New JIT Compiler for CRubyA team of skilled engineers from Shopify and GitHub on YJIT, a new Just-in-time (JIT) compiler built inside CRuby. The 1980s and 1990s saw the genesis of Perl, Ruby, Python, PHP, and JavaScript: interpreted, dynamically-typed programming languages which favored ease of use and flexibility over performance. In many ways, these programming languages are a p