Paweł Lesiecki plesiecki

Running nightmare on Amazon Linux

You may have thought of running nightmare on AWS Lambda. But before we can run it on Lambda, we need first to make it run on Amazon Linux.

Provision instance which replicates Lambda environment

According to AWS Documentation on Lambda Execution Environment and available Libraries we would need this AMI image with this alias amzn-ami-hvm-2016.03.3.x86_64-gp2. Keep in mind that AMI-image-id for this instance would be different in different regions (eg):

In eu-west-1 - ami-f9dd458a
In us-east-1 - ami-6869aa05

This is a proposal for lightning talk at Reactive Conf. Please 🌟 this gist to push the proposal!

Memory Leak Testing in 2017

Hi, I am Andy, creator of leakage - the node-powered memory leak testing library.

Instead of manual debugging it provides a structured approach to fix or even prevent memory leaks.

Analysis of `passive: true`

In 2017, Chrome, Firefox and Safari added support for passive event listeners. They help to make scrolling work smoother and are enabled by passing {passive: true} into addEventListener().

The explainer mentions that passive: true works for wheel and touch events. I practically analyzed when passive: true actually helps:

Event	Works better with `passive: true`	Is passive by default
`wheel`¹	Yes (Chrome), No (Firefox)	No (Chrome), No (Firefox)
`touchstart`	Yes (Chrome), ?² (Firefox)	Yes (Chrome), ?² (Firefox)

🐻 valoo

just the bare necessities of state management.

Usage

Hotlink it from https://unpkg.com/valoo.

See Interactive Codepen Demo.

`<script> async, defer, async defer, module, nomodule, src, inline` - the cheat sheet

This document is a comparison of various ways the <script> tags in HTML are processed depending on the attributes set.

If you ever wondered when to use inline <script async type="module"> and when <script nomodule defer src="...">, you're in the good place!

Note that this article is about <script>s inserted in the HTML; the behavior of <script>s inserted at runtime is slightly different - see Deep dive into the murky waters of script loading by Jake Archibald (2013)

Testing double-fetching of `module`/`nomodule` JS code (including the Safari hack)

<script type="module" src="module.js"></script>
<script nomodule src="nomodule.js"></script>

Update September 2020: life's almost good. Edge Chromium is widely rolled out, and Safari 14.0 ships soon with a fix.

Test page: https://jg-testpage.github.io/es-modules/module-nomodule/

	'use strict';

	var gulp = require('gulp');
	var through = require('through2');

	// https://gulp.readme.io/docs
	gulp.task('default', () => {
	gulp.src('src/*/')
	.pipe(pipeFunction())
	.pipe(gulp.dest('dist'))

	// UPDATE: In 2023, you should probably stop using this! The narrow version of Safari that
	// does not support `nomodule` is probably not being used anywhere. The code below is left
	// for posterity.

	/**
	* Safari 10.1 supports modules, but does not support the `nomodule` attribute - it will
	* load <script nomodule> anyway. This snippet solve this problem, but only for script
	* tags that load external code, e.g.: <script nomodule src="nomodule.js"></script>
	*
	* Again: this will not prevent inline script, e.g.:

	const range = function* (stop = 0, step = 1) {
	const shouldStop = (n)=>stop >= 0 ? (n < stop) : (n > stop);
	const interval = (n)=>stop >= 0 ? n + step : n - step;
	let itr = function*() {
	let i = 0;
	while (shouldStop(i)) {
	yield i;
	i = interval(i);
	}
	};

	import svelte from 'rollup-plugin-svelte';
	import resolve from 'rollup-plugin-node-resolve';
	import commonjs from 'rollup-plugin-commonjs';
	import buble from 'rollup-plugin-buble';
	import uglify from 'rollup-plugin-uglify';
	import postcss from 'postcss';
	import postcssImport from 'postcss-import';
	import postcssCssnext from 'postcss-cssnext';

	const production = !process.env.ROLLUP_WATCH;