Warfley, why Pascal is unsafe language?
Python, Javascript and PHP there is a problem with all described languages. They all are sometimes extremely slow. I built some time ago an application with JS that working a lot with strings and performance and resource usage was absolutely disappointing. Warfley, what do you say about Rust, is it safe enough for web servers?
Unsafe with programming languages refers to type and memory safety. Pascal is relatively typesafe (as long as you dont cast around to much, use untyped pointers or use absolute or other such constructs), but is absolutely not memory safe.
You can avoid some of those safety issues with CGI apps, which is why I always recommend to write your webserver as such when using pascal.
About performance, HTTP is a plaintext based request response protocol that requires TLS handshakes for each connection and then to be handled by the Browser. This means any request will just because of network traffic take tens if not hundreds of milliseconds to complete. The execution time of the programming language is absolutely negligible in those cases.
For most Webservers a jit compiled java, js or python app will be more than enough. Even relatively complex computations like string processing in those languages will not impact the overall response time simply because the deciding factor here is network delay. It doesn't matter if your code takes 10ms instead of 100nanos if the HTTP overhead is 200ms.
About rust, yes rust is safe and fast and has some good frameworks for web servers. But again you are optimizing something that you probably don't need to optimize. Execution speed is rarely if ever the bottle neck for web apps