Use `dbg` for prying. You can also use `break!` in an `iex` session to manually set breakpoints without modifying your source. Additionally, you can use Erlang’s `:debugger`for visual debugging, and `:observer` for understanding the entire VM when prying is not enough.

`dbg` is relatively new but [IEx.pry](https://hexdocs.pm/iex/IEx.Pry.html) has been around for a long itme

This is not nor has not ever been true.

Now, you've got `dbg()` and running whatever you're running via `iex -S <whateveryouweredoinghere>`.

Prior to `dbg()` you had `IEx.pry()`.