> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/perl6-rosettacode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/perl6-rosettacode/programming_tasks/s/start_from_a_main_routine.md).

# Start from a main routine

When executed with the standard setting, Raku code always runs the mainline code automatically, followed by the `MAIN` function if you have one. However, it's possible to start up with an alternate setting that might want to create its own event loop or `MAIN`. In such cases you can always capture control at various phases with blocks that we call "phasers":

```perl
BEGIN {...} # as soon as parsed
CHECK {...} # end of compile time
INIT {...}  # beginning of run time
END {...}   # end of run time
```


---

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