I prefer something like specs[1] that define a function’s signature but isn’t enforced by the compiler, instead the linter enforces them.

This is what Erlang has and it’s very convenient since once a design is fixed, I end up writing a spec to remind me what types the function expects.

[1] = https://www.erlang.org/doc/system/typespec.html

I really don't get how having to write

  @spec foo(String.t()) :: String.t()
  def foo(bar)

is better than

  def foo(String.t() bar): String.t()

Anxious about what? What's your issue with dynamic typing?

Thorough tests of the behavior of your system (which should be done whether the language is dynamic or not) catch the vast, vast majority of type errors. "More runtime errors" in a well designed codebase don't mean errors for the user - it means tests catch them

Seriously.. the secret to writing great dynamic code is getting very good at testing

I come from a PHP and Python background. I can see how progressive addition of types has changed the way we deal with code. Working on a big old project without types is not even possible for me anymore. Refactoring things with types is already such a tedious task. Without it it's barely possible.

The thing is most useful for me about types is it serves as forced documentation. I look at function signature with types and know what kinds of values it accepts and what it returns.

For sure. The biggest advantages of static types I see is the better tooling + faster feedback for type errors. They're advantaegs but not that big of a deal and they're equal to the tradeoffs you're making to where it doesn't matter much

I see dynamic codebases being written differently though. We all know those tradeoffs - so conventions pop up to deal with them. A method that ends in a ? in ruby - like user.admin? - always returns a boolean. You get better at naming to make types clearer

I definitely miss the perfect automated refactorings though

I knew TS's type system went too far when I saw the 8 queens problem solved in just the type system, not the actual language. Me, I just want to get stuff done, not fight my type system.

And that was even before someone wrote DOOM in TS's type system.