I'm writing this mostly so that I can move on from the project, because I really don't have much motivation to work on it.
I saw a post about the possibility of a Mastodon client for the 3DS, and I figured I would give it a try, since I have the knowledge to do it. However, what I don't have is the motivation. It takes a lot of effort to build something like this for a system with little to no libraries that you need, and I would rather spend my efforts on something more practical. The source code is available, for those who want to look at it and adapt it.
One of the largest challenges of getting it to work was networking. I chose to use Rust, which was probably a good idea, because its large crate ecosystem made it easy to find libraries to implement what I need. However, most networking and async I/O libraries are designed only for major operating systems (reasonably!), so after much frustration with networking crates, I decided to use networking libraries provided by the devKitPro package repositories, as they are built for the 3DS.
At first, I tried to use mbedTLS, and then use Rust crates for HTTP parsing, but it would not work. I then switched to using cURL. The API is very aptly named, curl_easy is very easy to use! I couldn't use the Rust cURL bindings because they depend on some things that aren't implemented for the 3DS, but making my own bindings wasn't much trouble.
Additionally, I needed to implement a graphical interface. I used citro2d, but needed to implement text rendering myself, in order to implement word wrapping in a way that let me know the height of the text blocks. I also separated the graphics and logic threads, though there's not much advantage to that in the current state of the application.
At the moment, you can't even send toots at the same time as viewing posts. I could probably implement this, but I don't really feel like it.
Maybe someday I'll feel like adding to this application, or cleaning it up, but for now, I'd rather work on other projects, but I don't want to drop this project without writing something about it.
(also I didn't want to upload the theming changes to the site without another blog post)