README.md

cargo build --release
go build -trimpath
node index.js

actix.rs

use actix_web::{web, App, HttpResponse, HttpServer, Responder};

async fn index() -> impl Responder {
    HttpResponse::Ok()
        .header("Content-Type", "text/plain; charset=utf-8")
        .body("Hello world!")
}

#[actix_rt::main]
async fn main() -> std::io::Result<()> {
    HttpServer::new(|| {
        App::new()
            .route("/", web::get().to(index))
    })
    .bind("127.0.0.1:8088")?
    .run()
    .await
}

fasthttp.go

package main

import "github.com/valyala/fasthttp"

// request handler in fasthttp style, i.e. just plain function.
func fastHTTPHandler(ctx *fasthttp.RequestCtx) {
	ctx.Write([]byte("Hello world!"))
}

func main() {
	// pass plain function to fasthttp
	fasthttp.ListenAndServe(":8081", fastHTTPHandler)
}

nanoexpress.js

import nanoexpress from 'nanoexpress-pro';

const app = nanoexpress();

app.get('/', (req, res) => {
    return res.send('Hello world!');
});

app.listen(3000);