Awesome Open Source
Awesome Open Source


If you're starting a new project, Node++ is now recommended.


Silgy is an extreme speed asynchronous web application backend engine. It can render pages in microseconds, even with a database, when used with efficient DAO/ORM class (see live demo).

It's open-source and free.

It can act as:

  • a static web server;
  • a standalone, self-contained, single-process web application;
  • a standalone, multi-process web application, connected and load-balanced via standard POSIX queues;
  • an HTTP servlet/microservice that makes up a building block of the more complex, distributed architecture.

Why bother?

Back in 2015 I decided to write a web application and had a wishlist:

  1. It has to be responsive, in a way compiled programs used locally are responsive. It needs to feel solid and reliable. My application consistently gets "Faster than 100% of tested sites" badge from Pingdom.


  2. It needs to be universal. Silgy applications work on every currently used browser.

  3. Host it for free or at negligible cost. Websites that don't survive at least 10 years (or have a huge marketing budget) don't matter – it's not 1995 anymore. I wanted to make sure I'll be able to afford hosting for the rest of my life, or until users count would reach at least a million. I actually pay $3 per month for my ~1000 users' application and use ~1% of the server's resources.

  4. Security. Again, it's not 1995 anymore. Put your server online, set logLevel to 4 and see what's coming in. In literally few days you'll be flooded by bots trying every known hole in PHP, Wordpress and whatever-was-ever-cool. Silgy inverted the philosophy the older servers were once built on: instead of putting up the wall between the gates, Silgy is a fortress with a gate only where you want it. My application consistently gets grade A from SSL Labs.

    SSL Labs

  5. Independency. AWS getting nasty? It'd take 60 minutes to move anywhere else, most of them spent on setting up an account at my new cloud provider. Then I only need to install GCC, MySQL, restore database from backup, clone my repo, m, Enter and silgystart, Enter.

  6. Simplicity. Before writing my own web server, I tried a couple of libraries. They were either complicated, not intuitive, bloated or slow. Some look promising (Node.js), however database connections proved to be too slow for my needs. There's also a tendency for using every new fireworks that's available in town, like i.e. functional programming. I just don't feel comfortable with this, so I wanted straight, intuitive, procedural, single-threaded code. All the complexity needs to be hidden in the library.

  7. Beautiful URL. I want full/control/over/my/URIs.

  8. Planet-friendliness. Even if I could afford fat, 64-core, with terabyte of RAM server, why would I want to pay for that and waste the Earth? It turns out, data centers have become a major pollutant: Short BBC video on this.

As my wishes had come true, I decided to open my code and become famous. You're welcome.

IP2Location Demo

Here: is the simple demo web application using Silgy to log visitors with their location in database. It uses IP2Location™ LITE IP-COUNTRY free database. Live instance:

Node++ announcement

I am starting working on Silgy's successor: Node++. As I gathered a lot of experience from writing about 20 web applications myself and helping others, I feel I'm ready to take a bigger step to the new name and a few breaches that will, I believe, make Silgy applications better. No worries: I'll be supporting Silgy project for at least a year from the first Node++ stable release and will provide an automated conversion tool for existing applications, as I will need this myself.

I need to thank you all for all your questions, encouragement and kind words!

Please keep asking, suggesting and express your wishes: here in Issues or [email protected].


What's in the box?

As I am writing this in May 2019, Silgy lib contains everything that is necessary to build a complete, production-grade solution, including session management, users accounts, REST calls and multi-language support.

The only third-party dependencies are:

  • USERS module requires MySQL library.

  • HTTPS requires OpenSSL library.

Silgy Hello World handles ~20,000 requests per second on a single CPU, free AWS instance.

Silgy has build-in (and enabled by default) protection against most popular attacks, including BEAST, SQL-injection, XSS, and password and cookie brute-force. It does not directly expose the filesystem nor allows any scripting. Its random string generator is FIPS-compliant. CSRF protection is as easy as adding 3 lines to the code.

TCO for a mid-sized web application with a small database and moderate load (<1,000,000 requests/day) can be as low as $3 per month (Amazon EC2 t2.micro).

In case of using Silgy under heavy load or with external API calls, there's the ASYNC facility designed to prevent main (silgy_app) process blocking. ASYNC allows developer to split (or move) the functionality between gateway and multiple service processes.

Getting Started on Windows

Getting Started on Linux

Silgy functions and macros

Full documentation

Generate RESTful API as Silgy project

Hello Worlds

Empty application = static web server

This is just an extremely fast static web server. If no resource is requested it'll look for index.html in res directory. If requested file is not present in res nor resmin, it'll return 404.

void silgy_app_main(int ci)

Simplest Hello World

Return static file if present, otherwise "Hello World!".

void silgy_app_main(int ci)
    OUT("Hello World!");

Simple HTML with 2 pages

Application, yet without moving parts.

void silgy_app_main(int ci)
    if ( REQ("") )  // landing page
        OUT("<h1>%s</h1>", APP_WEBSITE);
        OUT("<h2>Welcome to my web app!</h2>");
    else if ( REQ("about") )
        OUT("<h1>%s</h1>", APP_WEBSITE);
        OUT("<p>Hello World Sample Silgy Web Application</p>");
        OUT("<p><a href=\"/\">Back to landing page</a></p>");
    else  // page not found

Using query string value

Finally some logic. QS() will automatically choose between query string or payload, depending on the HTTP request method.

void silgy_app_main(int ci)
    if ( REQ("") )  // landing page

        OUT("<h1>%s</h1>", APP_WEBSITE);
        OUT("<h2>Welcome to my web app!</h2>");

        if ( REQ_DSK )
            OUT("<p>You're on desktop.</p>");
        else  /* REQ_MOB */
            OUT("<p>You're on the phone.</p>");

        OUT("<p>Click <a href=\"/welcome\">here</a> to try my welcoming bot.</p>");

    else if ( REQ("welcome") )  // welcoming bot
        OUT("<h1>%s</h1>", APP_WEBSITE);

        OUT("<p>Please enter your name:</p>");
        OUT("<form action=\"welcome\"><input name=\"firstname\" autofocus> <input type=\"submit\" value=\"Run\"></form>");

        QSVAL qs_firstname;   // query string value

        if ( QS("firstname", qs_firstname) )    // if present, bid welcome
            OUT("<p>Welcome %s, my dear friend!</p>", qs_firstname);

        OUT("<p><a href=\"/\">Back to landing page</a></p>");

    else  // page not found

Real world application example

Silgy Home Page source code. You can try it live at


Although not necessary, it's good to have $SILGYDIR set in the environment, pointing to the project directory. Silgy engine always first looks in $SILGYDIR/<dir> for the particular file, with <dir> being one of the below:


(Required only for development)

  • Application sources. It has to contain at least silgy_app.h and silgy_app.cpp with silgy_app_main() inside.
  • Compilation script: m


(Required only for development)

  • Silgy engine & library source
  • users.sql


  • Executables, i.e. silgy_app, silgy_svc, silgy_watcher
  • Runtime scripts, i.e. silgystart, silgystop
  • Configuration: silgy.conf
  • Strings in additional languages: strings.LL-CC
  • Blacklist, i.e. blacklist.txt
  • Whitelist, i.e. whitelist.txt
  • 10,000 most common passwords: passwords.txt


Static resources. The whole tree under res is publicly available. All the files are read on startup and served straight from the memory. File list is updated once a minute.

  • images
  • static HTML files
  • text files
  • fonts
  • ...


Static resources to be minified. The whole tree under resmin is publicly available. All the files are read on startup, minified and served straight from the memory. File list is updated once a minute.

  • CSS
  • JS


Static parts of rendered content, i.e. HTML snippets.


  • Log files

Feedback & Support

Write to [email protected] if you got stuck, need a feature or have a side gig for me. I have reasonable prices but need advance booking. Please report bugs in Issues.

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