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Kris Kowal kriskowal

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kriskowal / evil.js
Last active August 31, 2022 14:12
// So, in sloppy mode, eval and var can do interesting things.
globalThis.name = 'global';
console.log(name === 'global');
(function () {
const name = 'outer';
// direct eval, using a var declaration.
(function () {
@kriskowal
kriskowal / compartment.js
Last active July 9, 2022 00:59
class Compartment {
#modules = new Map();
#descriptors = new Map();
#referrers = new Map();
#globalThis = Object.create(null);
constructor({ resolveHook, loadHook, globals }) {
this.#resolveHook = resolveHook;
this.#loadHook = loadHook;
this.#importHook = async (importSpecifier, importMeta) => {
@kriskowal
kriskowal / modules-harmony.md
Created July 1, 2022 22:01 — forked from caridy/modules-harmony.md

Modules Harmony Simplification Effort

Disclaimer: This text is exclusively focused on the existing capabilities of the language, and does not weight into additional capabilities like wasm, or virtual modules, or compartments. Those can be discussed later on.

MVP to create a module graph

The bare minimum mechanism to create a module graph that matches ESM requires few main pieces:

  1. A portable (serializable) structure that represents the source text of the module. ModuleSource must be portable across processes and across realms.
  2. A realm based Module that closes over a ModuleSource.
@kriskowal
kriskowal / temp.js
Created June 14, 2022 23:31
export { star as '*' };
const star = 42;
@kriskowal
kriskowal / mutex.js
Created June 13, 2022 06:05
let mutex = Promise.resolve();
const protocol = {
command() {
const result = mutex.then(() => {
// mutual exclusion
});
mutext = next.catch(() => {});
return result;
},
close() {
@kriskowal
kriskowal / for-defer-of-go.js
Last active May 20, 2022 23:11
const go = {
[Symbol.iterator]() {
const funcs = [];
const defer = func => funcs.push(func);
let index = 0;
const flush = () => {
let func;
while (func = funcs.pop()) {
func();
}
@kriskowal
kriskowal / uber-to-agoric.md
Last active May 10, 2022 22:51
Uber to Agoric

I have a bit of good news and bad news. Friday, April 3, was my last day at Uber. Monday, April 6, was my first day at Agoric.

I started at Uber 5½ years ago, on the dispatch system. I joined Tom Croucher’s team, which focused on common frameworks for marketplace systems, with Jake Verbaten, Russ Frank, and spiritually Matthew Esch. When I arrived, the scaffolding and frameworks were in place. I wrote a tool for verifying that JSON schema evolution remained backward-compatible, did some weird stuff to automatically mix the middleware stack, and wrote a thing to balance load across Node.js processes more fairly than the Linux kernel. I don’t believe any of that work made it to production, really, but for those six months, I learned how to operate global dispatch while I was on-call for 24 hours once a month and developed a bald spot.

I then got on board a new Distributed Systems Group under Matt Ranney’s guidance and many of the folks I’ve been working with to this day. Matt had designed a DHT based on the S

@kriskowal
kriskowal / teleprompter.html
Created November 11, 2021 22:47
<!doctype html>
<head>
<style>
* {
font-family: Helvetica;
font-size: 180px;
}
body {
padding: 50px;
}
@kriskowal
kriskowal / timers.js
Last active August 29, 2021 04:51
const {setTimeout, clearTimeout} = globalThis;
const handles = new WeakMap();
globalThis.setTimeout = (callback, ms) => {
if (typeof callback !== 'function') {
throw new Error(`This implementation of setTimeout has disabled evaluation behavior for ${typeof callback} callbacks`);
}
const token = harden({});
handles.set(token, setTimeout(callback, ms));
return token;
};
@kriskowal
kriskowal / potter.md
Last active August 14, 2021 19:20
On the incompetence of Albus