PHP has had optionally typed function parameters and return values since the late 5.x releases I think (current release is 7.3). Types are checked at runtime and throw TypeErrors if the declared types are violated. They can also be checked ahead of time by IDEs with code inspection such as PhpStorm.

The 7.4 release is adding typed class properties as well[1].

I maintain a ~75k LOC PHP codebase (using the Laravel framework), and we have almost never encountered type issues. The new style of PHP (and Javascript is heading in a similar direction tbh) is to write it almost like it's Java, but with the option to fall back to dynamic "magic" as needed. If you utilize the dynamic elements sparingly, and following widely understood conventions, the productivity-vs.-reliability tradeoff is highly favorable for many applications compared to languages like Java and C#.

P.S. I like Python, but I would argue PHP actually has a better story to tell about types these days. "While Python 3.6 gives you this syntax for declaring types, there’s absolutely nothing in Python itself yet that does anything with these type declarations..." [2]. Declaring types in a dynamic language only to have them ignored at runtime does not inspire much confidence.

1. https://laravel-news.com/php7-typed-properties

2. https://medium.com/@ageitgey/learn-how-to-use-static-type-ch...