ENenos_feedler·Jun 11, 2026
It works in the browser already: https://github.com/bytecodealliance/jco
In The Road to the WASM Component Model 1.0bytecodealliance
jco
TypeScript2023–2026
bytecodealliance / jco
jco
JavaScript toolchain for working with WebAssembly Components
10Distinct people
17Mentions
0Explicit recommenders
1KGitHub stars
What to know before exploring
What it is
JavaScript toolchain for working with WebAssembly Components
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.
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Also in these discussions
- bytecodealliance/componentize-py · linked in 2 of the same discussions
- bytecodealliance/wit-bindgen · linked in 2 of the same discussions
Mentioned in the same Hacker News threads. That is not proof they are substitutes.
This week on Hacker News
Nov 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 2:04:58 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 year17 dated mentions
Observed mentions: 2023-04-20 04:17:37 UTC to 2026-06-11 05:03:48 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
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 |
|---|---|---|---|---|---|
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 8 | 0 | 8 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 4 | 1 | 3 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 2 | 0 | 2 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 3 | 0 | 3 |
What Hacker News says
3 sourcesIf you’d like to get acquainted with modern WebAssembly, check out the component model book:
https://component-model.bytecodealliance.org/
It includes high level concepts, practical code samples and more that introduce the really powerful parts of WebAssembly.
With regards to the JS ecosystem specifically there are 3 projects to know:
https://github.com/bytecodealliance/StarlingMonkey
https://github.com/bytecodealliance/ComponentizeJS
https://github.com/bytecodealliance/jco
The most mature tool chain right now is Rust, but there is good support for most things with LLVM underneath (C/C++ via clang). Golang, python and support for other languages is getting better and better (tinygo and big go) and there’s even more to come.
One of the goals of WebAssembly is to melt right into your local $TOOLCHAIN as a compilation target, and we are gett
Read the rest
ing closer every week.
There's also JCO for creating JS based WebAssembly components. It's based on StarlingMonkey which I believe is slightly faster than QuickJS under web assembly. https://github.com/bytecodealliance/jco
Benchmark numbers for request isolated JS hello world / React page rendering:
JCO/wasmtime: 314µs / 13ms
Bun process forking: 1.7ms / 8.2ms
v8 isolate from snapshot: 0.7ms / 22ms
TinyKVM: 52µs / 708µs
Native with reuse 14µs / 640µs
Numbers taken from our upcoming TinyKVM paper. Benchmark setup code for JCO/wasmtime is here: https://github.com/libriscv/kvmserver/tree/main/examples/was...
(I suspect even if we are able to get TinyKVM into a state you'd feel comfortable with in the future it would still be an awkward fit for Datasette since nested virtualisation is not exposed on AWS EC2.)
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