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@charlespwd
charlespwd / make-mp4-from-profile
Last active November 1, 2020 09:19
Make a mp4 from a Chrome DevTools Performance Profile
#!/usr/bin/env bash
set -eou pipefail
profile=$1
frameRate=${2:-10}
timeline='timeline.json'
cat $profile \
| jq '.[] | select(.args.snapshot | . and (type == "string") and contains("/9j"))' \
| jq -s . \
> $timeline
@siddharthkp
siddharthkp / reactivconf-2017-proposal.md
Last active February 25, 2024 10:06
Building applications for the next billion users
@ianmcnally
ianmcnally / mock-css-modules-for-jest.js
Last active June 5, 2018 14:56
Mocks a directory of css files with a css-modules like object
const { parse } = require('css')
const { readdirSync, readFileSync } = require('fs')
const { basename, extname, resolve } = require('path')
const camel = require('lodash.camelcase')
const baseNameForCSSFile = filename => basename(filename, '.css')
const isAClassSelector = selector => /^\./.test(selector)
const removeLeadingDotAndTrailingSelectors = selector =>
@stekhn
stekhn / prepareElastic.js
Last active April 13, 2023 00:52
Creates and prepares an Elasticsearch index, using the Node.js client. Closes the index before putting settings and mappings. The response and error handlers are optional, remove them if necessary.
var elastic = require('elasticsearch');
var client = new elastic.Client({ host: 'localhost:9200' });
var index = 'myindex';
var type = 'document';
(function init() {
Promise.resolve()
.then(deleteIndex, handleError)
@rauchg
rauchg / Readme.md
Last active September 30, 2024 17:11

Minimum Viable Async with Node 6

With the release of Node 6.0.0, the surface of code that needs transpilation to use ES6 features has been reduced very dramatically.

This is what my current workflow looks like to set up a minimalistic and fast microservice using micro and async + await.

The promise

@gaearon
gaearon / connect.js
Last active November 14, 2024 08:35
connect.js explained
// connect() is a function that injects Redux-related props into your component.
// You can inject data and callbacks that change that data by dispatching actions.
function connect(mapStateToProps, mapDispatchToProps) {
// It lets us inject component as the last step so people can use it as a decorator.
// Generally you don't need to worry about it.
return function (WrappedComponent) {
// It returns a component
return class extends React.Component {
render() {
return (
@kaleksandrov
kaleksandrov / global-protect.sh
Last active November 13, 2024 15:20
Simple script that starts and stops GlobalProtect.app on Mac OSX.
#!/bin/bash
case $# in
0)
echo "Usage: $0 {start|stop}"
exit 1
;;
1)
case $1 in
start)
@larahogan
larahogan / app-perf.md
Last active May 7, 2021 01:18
Native app performance metrics

Native app performance metrics

This is a draft list of what we're thinking about measuring in Etsy's native apps.

Currently we're looking at how to measure these things with Espresso and Kif (or if each metric is even possible to measure in an automated way). We'd like to build internal dashboards and alerts around regressions in these metrics using automated tests. In the future, we'll want to measure most of these things with RUM too.

Overall app metrics

  • App launch time - how long does it take between tapping the icon and being able to interact with the app?
  • Time to complete critical flows - using automated testing, how long does it take a user to finish the checkout flow, etc.?
  • Battery usage, including radio usage and GPS usage
  • Peak memory allocation