Compilation
When you render a .zing template for the first time, Zing compiles it to plain PHP and caches that output. On every render afterward, it uses the cached version.
The cache is invalidated automatically if the source .zing file changes — you don't need to clear anything yourself during development.
How it works in practice
This means you don't pay compilation costs on every request. Once a template is cached, rendering it is just an include() of a plain PHP file.
There's no runtime parsing, no AST walking, no per-request overhead.