zigself VS http.zig

I don't know about "daily" right now (I've had to take a break due to obligations), but I'm working on a modern implementation of the Self programming language with actor capabilities: https://github.com/sin-ack/zigself

It's nowhere near usable yet, but Zig has been a joy to work with for over a year, and I can definitely see myself using it for a big piece of software.

> Creating a language with the feel of a lisp, the environment of Smalltalk, and the concurrency of Erlang has been my dream for a long time.

I'm trying to eventually accomplish something like this: https://github.com/sin-ack/zigself

It's an implementation of the Self programming language in Zig, with an actor model inspired by Erlang.

The main thing to realize is that Lisp and Smalltalk are very much symmetrical in terms of structure. There is no real distinction between the two other than syntax and basic computation unit (closures vs. objects). And even closures can be used as objects and vice versa.

That only leaves the concurrency model. I have a basic implementation of actors using objects as the "context". It still has a long way to go to reach the supervisor tree model of Erlang, but interestingly enough, the ideas in the article are reflected here heavily; behaviorism is at the core of Self.

I have a somewhat popular HTTP server library for Zig [1]. It started off as a thread-per-connection (with an optional thread pool), but when it became apparent that async wasn't going to be added back into the language any time soon, I switched to using epoll/kqueue.

Both APIs allow you to associate arbitrary data (void ) with the event that you're registering. So when you're notified of the event, you can access this data. In my case, it's a big Conn struct. It contains things like the # of requests on this connection (to enforce a configured max request per connection), a timestamp where it should timeout if there's no activity. The Conn is part of an intrusive linked list, so it has a next: Conn and prev: *Conn. But, what you're probably most curious about, is that it has a Request.State. This has a static buffer ([]u8) that can grow as needed to hold all the received data up until that point (or if we're writing the data, then the buffered data that we have to write). It's important to have a max # of connections and a max request size so you can enforce an upper limit on the maximum memory the library might use. It acts as a state machine to track up to what point it's parsed the request. (since you don't want to have to re-parse the entire request as more bytes trickle in).

It's all half-baked. I can do receiving/sending asynchronously, but the application handler is called synchronously, and if that, for example, calls PG, that's probably also synchronous (since there's no async PG library in Zig). Makes me feel that any modern language needs a cohensive (as in standard library, or de facto standard) concurrency story.

[1] https://github.com/karlseguin/http.zig

I took a year off, and one of the things I did was learn Zig. I've built a number of libraries, including one of the currently more popular HTTP server libraries (https://github.com/karlseguin/http.zig).

A number of my libraries are used for https://www.aolium.com/ which I decided to write for myself.

I try to write a bit every day with the benefit that I can "waste" time digging into things or exploring likely-to-fail paths.