Reproducible builds

[lrettig]

Note: we'll have to use dockerized build for this. See https://docs.succinct.xyz/writing-programs/compiling.html#production-builds.

[schinzelh]

What's your preference here? Something like Guix?

[lrettig]

It's not something I know a lot about, and I don't have a strong preference. Ideally it could be done using just Docker (see Telegram example), but this may not be possible with Rust. My understanding is that Rust support for reproducible builds is still a work in progress. Welcome any contributions here.

[lrettig]

I tried doing some work on this in #49, just to ensure that the examples and tests are built deterministically. I tried obvious things like adding the relevant Cargo.lock files, ensuring the toolchain matches, etc., to no avail. I saved the work in #51. Let's revisit this later.