C++ vs Material Design for Angular

I am currently learning Back-End design, and I am confused with the term Back-End API. My question is do I need to have a webserver? That is the Browser send a http request to the Webserver, based on the URL, the Webserver will execute the WEB API and route the request to it and send back the response received from the WEB API to the browser. If so, what are the differences from the WebServer to execute a CGI in the traditional architecture?

If this is not the case, is the WEB API a standalone server/application that can process the HTTP request and send back the response to the browser? Thank you very much for clarifying...

As a personal research project I wanted to add post-quantum crypto KEM (key encapsulation) algorithms and new symmetric crypto session algorithms to openssh. I found the openssh code and its channel/context management extremely complex.

Concurrently, I was learning Go. It occurred to me that Go's excellent standard library, including crypto libraries, plus its much safer memory model and string/buffer handling would be better suited to a secure remote shell solution. So I started from scratch, writing a clean-room Go-based solution, without regard for ssh compatibility. Interactive and token-based login, secure copy and tunnels.

Of course, it needs a proper security audit for side channel attacks, protocol vulnerabilities and so on -- but I was impressed by how much simpler a client-server application with crypto and complex terminal handling was in Go.

<pre> $ sloc openssh-portable Languages Files Code Comment Blank Total CodeLns Total 502 112982 14327 15705 143014 100.0% C 389 105938 13349 14416 133703 93.5% Shell 92 6118 937 1129 8184 5.7% Make 16 468 37 131 636 0.4% AWK 1 363 0 7 370 0.3% C++ 3 79 4 18 101 0.1% Conf 1 16 0 4 20 0.0% $ sloc xs Languages Files Code Comment Blank Total CodeLns Total 34 3658 1231 655 5544 100.0% Go 19 3230 1199 507 4936 89.0% Markdown 2 181 0 76 257 4.6% Make 7 148 4 50 202 3.6% YAML 1 39 0 5 44 0.8% Text 1 30 0 7 37 0.7% Modula 1 16 0 2 18 0.3% Shell 3 14 28 8 50 0.9% </pre>

https://gogs.blitter.com/RLabs/xs