To those interested in trying Rust with RISC-V but not in possession of the HiFive boards, if you have a FPGA laying around, you can synthesize the PicoRV32 RISC-V CPU on some Lattice iCE FPGAs and run Rust on it with support provided by the picorv32 crate. There is another RISC-V soft core called VexRiscv which also has Rust support in the vexriscv crate.
Off-topic, but a piece of feedback on your website: the text is so light, against a light background, that it is hard to read for me. I think this is because of the combination of color: #606c76, which has a contrast ratio of only 5.3 to 1, and font-weight: 300 — disabling either of these CSS rules removed the eyestrain for me. I think that because the font becomes so thin, the anti-aliasing reaches nearly to the middle of the strokes, and that makes the effective gray lighter and the contrast lower.