alt Hacker NewsA Modern Web App in C
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My favorite trivia is that busybox has built-in cgi-bin support (and `rclone serve webdav` seems remiss to not mention as well). `https://elixir.bootlin.com/busybox/1.37.0/source/networking/...`
Everything the post mentions is 100% true and well-reasoned, especially with the inclusion of pledge/chroot/etc. for dropping privileges.
There's two diametrically opposed deployment mechanisms:
1) stack towers of glop on top of each other until you're running a simple `echo "hello world"` on top of a docker container inside a vm in a proxmox server as part of a k8s cluster under a hypervisor running on remote compute...
2) just run `bash -c 'echo "hello world"'` and front it with CGI (stateless, single binary, yada yada yada...)
Take a peek at https://github.com/Domain/bash.cgi ... not that i'm suggesting that 'bash over busybox using cgi-bin' is the "proper architecture", it's more trying to illustrate that the amount of code that holds you back from being nearly truly "frameworkless" is tiny and easy to reason about.
For some of the internal tooling I'm doing for work, I've been tending towards:
some-cmd [--json|--markdown] ...yet-more-args...
For people who find interest in weird web applications, I have been working on a game project, in C++, where the client is compiled to WebAssembly with Emscripten, and the application server is also implemented in C++ (behind nginx).
This is from pre-AI era also. The game is Civ-like. Custom engine from scratch (including both the 3D stuff, and all the web handling also).
Take a look: https://statebuilder.com/
A Go binary with CGO=0 and all templates/documents embedded gives you a better overall tooling and deployment experience. Put it in a scratch container for complete isolation.
CGI is great. Sadly nginx doesn't support it natively as opposed to lighttpd.
I like this project for adding CGI to nginx: https://github.com/pjincz/nginx-cgi
There's also methods of starting Rack applications directly form nginx via passenger[1]. Rack is the CGI like interface for ruby webapps: https://github.com/rack/rack It easily allows for writing applications and middleware with a few lines of ruby.
[1]: https://www.phusionpassenger.com/documentation/Users%20guide...
came back to C/C++ for same reasons, no supply chain trouble, fits in my head, runs forever, ... here a playground for win32, using partially webview2, all batteries included, openai client , tts, stt, vpl, images, audio, video, ... comes with webview2 apps, settings (and encryption), config, rest server, ipc, testing, CLI11, postgres, installer, doc gen, modbus, OpenCV, daemon, computer use, agent memory, image tools, mcp server/client, experimental flow editor - what a fun and exciting times :) https://github.com/polymech-info/win32-boilerplate
How about modern web apps in shell scripts only:
> There's no separate database server. You open the database file through SQLite's C API.
> Every request spawns a fresh process.
How does it work when multiple concurrent requests are possible? Does SQLite allow simultaneous write access from multiple processes?
I disagree with the first sentence. In 199x the first people I knew making web pages dropped perl scripts, not C programs, into cgi-bin.
It's not very clear to me why the author has chosen C in the first place. I appreciate the effort of sharing the experience with us, anyway.
I was not thinking about vanilla C and CGI but I wrote my own modern web api server app in C++ (std+boost only) and I found it extremely pleasant experience. very reliable and little supply chain/dependency hell problematic too.
It’s for intranet business app so although it’s not yet production ready yet, definitively winning against many other modern approaches in web development in my consideration, and quite refreshing POC project.
Author described good ole PHP 3.
Early PHP (3 and 4) were the thin layer over the C libraries and were pretty fast and easy. it came about right when CGI was deprecated and it solved CGI's problems
I am confused. Is this project open source? If yes, I could not find a link to the source code. Can someone help me?
I'm still in the middle of reading but I wanted to comment first that I had a pleasantly surprising experience a few years ago with CGI. I hadn't thought about CGI since I was a kid and I was tasked with adding a simple dynamic page to a server that had nothing running yet except apache. For whatever reason I though to try out CGI because of how simple the page was going to be, and yeah. Would recommend
I just got C FFI working in my LLVM based language last night so I'll need to take a look at playing around with BCHS :)
It hasn't been touched in a long time, maybe that's because it's "complete", but here's a quick CGI library:
A shame to hand code a project in C and then use AI to write a blog post.
It’s a cool project to test yourself but most of the benefits outlined would also apply to Go, Rust, etc, and then you also get memory safety thrown into the mix as well.
I worked on a FORTRAN 77 CGI application in the early 00s. I think the host was Apache httpd, on some old HPUX version.
Decent, but a half measure. Meaning you still depend on a separate web server (httpd in this case) to actually push your sites over the wire. This limits you in terms of how expressive your web application can be (ie you cannot arbitrarily write HTTP headers or choose how to serve your clients), and in terms of performance.
A far better (and harder approach) is to actually write the whole stack yourself. Meaning the actual web application and web server are packaged from a single binary. You of course have a myriad options in how to actually implement this (the server loop can run as a separate coroutine/thread/process/etc), but overall the performance and expressiveness flexibility is limitless. On top of that you can actually get blazing fast performance compared to classical approaches.
I'd also advise everyone to avoid CGI at all costs. It's overhead is massive (new process every time, more or less) and _itself_ is a half measure since implementing a proper code hot loading/module system for servers is too much of a hassle (and standardizing it is hard). Nowadays you want to inline your server and then handle HTTP generation separately (however you'd like).
I remember the days of wrangling cgi-bin on Linux hosts! Not a common paradigm these days..
Not open source, apparently. Am I missing something?
Does anyone know if Hacker News uses CGI as well? I know there's some JavaScript and AJAX magic for the interactive elements on the frontend.
Reminds me of the Vibe.d web framework for D lang. Good memories.
From the article, "WRITING HTML AND CSS IN C ISN'T TOO BAD".
Um, any and all string handling in C is pretty miserable.
"Every request spawns a fresh process" <- this is when I stopped reading to save some time for the latest news in AI. Apologies for an abrupt interrupt.
I still like writing web applications in PHP for many of the same reasons listed here - modern PHP anyways.
I shy away from frameworks unless I am building something that I expect a large team to work on, or I specifically need multiple complex features that don't make sense to maintain.
I've written a few applications for my own personal use or targeted at friends/family recently that have no third party dependencies other than Bootstrap, which I still like more than tailwind for anything that doesn't need to look like a marketing page.
> Everything about marketyour.games is modern
I can't read any of the text on that page other than the headings. Is that what makes it modern? I assume the stack mentioned in the blog post is vibe-slop as well.
Another interesting looking blog post that I can't bear to read without my eyes bleeding :(
"Every request spawns a fresh process. Deploying a new version is replacing one file. That means no server restart and no downtime. New requests simply pick up the new binary."
I think that's why FastCGI exists. It is the equivalent of PHP's "Swoole" or "FrankenPHP" or "amphp" or Laravel's "octane", etc. Each process is long-lived and tries to clean up its state as much as possible between requests. Forking a new process can take around 8ms (https://news.ycombinator.com/item?id=19005586)
When I was building https://github.com/Qbix/webserver in PHP, I was faced with forking a new process per request. I implemented fork-per-request at first, similar to PHP-FPM and then implemented the "FastCGI" approach of long-lived processes that clean up after each request. (Modern PHP has introspection so the engine can know what to clean up, before calling the php files to handle things.) However, some things are not really possible to completely reset in PHP, and you have to be careful with database connection pools, etc. Typically those are left open even by preforking processes like php-fpm.
Anyway, I ended up flipping it: use the "FastCGI" approach as a default, and if the original PHP code doesn't work (rare), then for that app, you can choose the regular CGI approach of forking a process per request. That way you get maximum speed by default, and manually opt into safety (this is an exception to my usual priorities).
PHP is actually quite fast. But I was also interested in transpiling it to C. So I built the transpiler at: https://ulanguage.org/playground ... used Claude to transform about 1000 PHP functions to their native equivalents, but if you use any of the others, it would hook into the Zend runtime and link with it. (There are some nuances with zvals and objects, and resources in previous PHP versions, but I managed to overcome them.) By the way, it also works with Node and Python FFI the same way.
You can basically now take PHP, Python or Javascript/Typescript code, and speed up the CPU-bound parts about 10-50x. A lot of that is because of string and JSON handling. Many web apps use strings and JSON a lot. So underneath, I had the compiler use "ropes" for the strings, and avoid concatenation. It also parallelizes the JSON encode and decode into code that can run on multiple cores at once, i.e. large JSON payloads are encoded and decoded in parallel. Those are just huge speedups.
Anyway... all of this is mostly focused on speed optimization, so you can solve the literally C100K problem (forget C10K) today, on a regular box. If you don't need speed or FastCGI, your approach is fast enough for the vast majority of applications.
PS: By the way, if you fork after your program already loaded the framework and initialized the configuration, then you can run a lot more workers, literally 10x-100x more of them, because Linux and Mac will share all the loaded memory between processes, and do Copy-On-Write only on dirty pages. And when your request is done, and the process exits, that custom memory is efficiently cleaned up by the OS. It is this feature that allowed me to finally get the best of both worlds... run all existing PHP code, that makes blocking I/O requests all over the place to the database, filesystem, network etc. while at the same time being able to handle 100,000 requests in flight at the same time! Swoole and FrankenPHP can't do that.
Golang also makes it possible to serve a web site or service from a single binary. You can even avoid linking libc if you stick to core Go (CGO_ENABLED=0), and it comes with all the http and tls libraries you need to replace the traditional web server (nginx, apache, httpd) as well.
I love C and wrote some CGIs in C in the past but I don't love concurrent programming in C. While forking and execing can use shared read-only mmap on .text segments, the .bss and .data will need initialization and copying; there's unavoidable startup overhead that a threaded process avoids, and raw pthreads is kind of painful. If all you need to do is serve a low traffic site, CGI is fine.
My biggest worry would be how often the SQLite DB gets backed up because there's no way a C web server will be free of RCEs in today's world.