ANangelmm·Aug 3, 2022Submission
Wain: WebAssembly implementation from scratch in Safe Rust with 0 dependencies
2 points · Open discussionrhysd
wain
Rust2022–2022
rhysd / wain
wain
WebAssembly implementation from scratch in Safe Rust with zero dependencies
2Distinct people
2Mentions
0Explicit recommenders
462GitHub stars
What to know before exploring
What it is
WebAssembly implementation from scratch in Safe Rust with zero dependencies
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
No recommendation phrase was found in the indexed comments.
No classified warning is attached to this page. Read the discussions before treating silence as approval.
Also in these discussions
No other repository is repeatedly linked in the same discussions.
This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 3:56:07 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by day2 dated mentions
Observed mentions: 2022-07-25 05:06:51 UTC to 2022-08-03 06:37:06 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| Jul 25 | 2022-07-25 00:00:00 UTC | 2022-07-26 00:00:00 UTC | 1 | 0 | 1 |
| Jul 26 | 2022-07-26 00:00:00 UTC | 2022-07-27 00:00:00 UTC | 0 | 0 | 0 |
| Jul 27 | 2022-07-27 00:00:00 UTC | 2022-07-28 00:00:00 UTC | 0 | 0 | 0 |
| Jul 28 | 2022-07-28 00:00:00 UTC | 2022-07-29 00:00:00 UTC | 0 | 0 | 0 |
| Jul 29 | 2022-07-29 00:00:00 UTC | 2022-07-30 00:00:00 UTC | 0 | 0 | 0 |
| Jul 30 | 2022-07-30 00:00:00 UTC | 2022-07-31 00:00:00 UTC | 0 | 0 | 0 |
| Jul 31 | 2022-07-31 00:00:00 UTC | 2022-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 1 | 2022-08-01 00:00:00 UTC | 2022-08-02 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2 | 2022-08-02 00:00:00 UTC | 2022-08-03 00:00:00 UTC | 0 | 0 | 0 |
| Aug 3 | 2022-08-03 00:00:00 UTC | 2022-08-04 00:00:00 UTC | 1 | 1 | 0 |
What Hacker News says
2 sourcesI think SIMD was a distraction to our conversation, most code doesn't use it and in the future the length agnostic, flexible vectors; https://github.com/WebAssembly/flexible-vectors/blob/master/... are a better solution. They are a lot like RVV; https://github.com/riscv/riscv-v-spec, research around vector processing is why RISC-V exists in the first place!
I was trying to find the smallest Rust Wasm interpreters I could find, I should have read the source first, I only really use wasmtime, but this one looks very interesting, zero deps, zero unsafe.
16.5kloc of Rust https://github.com/rhysd/wain
The most complete wasm env for small devices is wasm3
20kloc of C https://github.com/wasm3/wasm3
I get what you are saying as to be so small that there isn't a place of bugs to hide.
> “There are two ways of constructing a software design: One w
Read the rest
ay is to make it so simple that there are obviously no deficiencies, and the other way is to make it so complicated that there are no obvious deficiencies. The first method is far more difficult.” CAR Hoare
Even a 100 line program can't be guaranteed to be free of bugs. These programs need embedded tests to ensure that the layer below them is functioning as intended. They cannot and should not run open loop. Speaking of 300+ reimplementations, I am sure that RISC-V has already exceeded that. The smallest readable implementation is like 200 lines of code; https://github.com/BrunoLevy/learn-fpga/blob/master/FemtoRV/...
I don't think Wasm suffers from the base extension issue you bring up. It will get larger, but 1.0 has the right algebraic properties to be useful forever. Wasm does require an environment, for archival purposes that environment should be written in Wasm, with api for instantiating more envs passed into the first env. There are two solutions to the Wasm generating and calling Wasm problem. First would be a trampoline, where one returns Wasm from the first Wasm program which is then re-instantiated by the outer env. The other would be to pass in the api to create new Wasm envs over existing memory buffers.
See, https://copy.sh/v86/
MS-DOS, NES or C64 are useful for archival purposes because they are dead, frozen in time along with a large corpus of software. But there is a ton of complexity in implementing those systems with enough fidelity to run software.
Lua, Typed Assembly; https://en.wikipedia.org/wiki/Typed_assembly_language and Sector Lisp; https://github.com/jart/sectorlisp seem to have the right minimalism and compactness for archival purposes. Maybe it is sectorlisp+rv32+wasm.
If there are directions you would like Wasm to go, I really recommend attending the Wasm CG meetings.
https://github.com/WebAssembly/meetings
When it comes to an archival system, I'd like it to be able to run anything from an era, not just specially crafted binaries. I think Wasm meets that goal.
https://gist.github.com/dabeaz/7d8838b54dba5006c58a40fc28da9...