glean VS rust

We do what cargo-lipo recommends: Adjust the library search path per target, build your library as normal per target and Xcode will figure out the rest. That works perfectly fine. We ship our library as an xcframework within a Swift package now. Applications can then rely on the Swift Package Manager to do its thing. (At some point I should write this up nicely in a blog post or something I guess...)

Yup, NDK 21 works just fine. We've been using that in our Android projects for a long time now.

I suspect they'll just use Mozilla's very own telemetry SDK

The esp-template issue might be this one: https://github.com/esp-rs/rust/issues/158. Try with --release or updating to 1.68.0 with espup update. I'll take a look at the log as soon as I can, atm Im on the phone and is not that easy to scroll through :(

Sure. Espressif maintains a fork which adds support for their microcontrollers.

I am trying to make a vaccine passport validation for my country using the ESP32 for my micro controller. I have gotten the std rust library to compile using (esp-rs)[https://github.com/esp-rs/rust], but the actual validation library that I use needs openssl which refuses to compile.

Xtensa. They've got a fork of LLVM that supports it that they're working toward getting upstreamed. The community has a fork of rustc that uses it (and a quickstart crate) while we wait for it to get upstreamed.

It only works if you have an Xtensa compiler which takes hours to compile, here: Rust Xtensa (if you don't have it). The network driver is just a function that sets the name of the driver so the Esp32 does something other that blinking.