We do similar (strict_types, declare parameter and return types, etc), but don't go as far as the Java-style collection classes except where absolutely necessar

We do similar (strict_types, declare parameter and return types, etc), but don't go as far as the Java-style collection classes except where absolutely necessary. As a mostly-acceptable alternative, we just type hint as array and document the actual containing types in the phpdoc block and run phan for static analysis to catch any potential screwups. /** * Method for converting Foos into Bars * * @param Foo[] $foos * @return Bar[] */ function convertFoosToBars(array $foos): array { // ... } In theory this isn't perfect. In practice we haven't run into any issues yet.