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God and Puma configuration

Add to Gemfile:

gem 'puma'
gem 'god'

Run in app folder:

bundle install

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tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

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Note: these are pretty rough notes I made for my team on the fly as I was reading through some pages. Some could be mildly inaccurate but hopefully not terribly so. I might resort to convenient fiction & simplification sometimes.

My top contenders, mostly based on popularity / community etc:

• Angular
• Backbone
• React
• Ember

Mostly about MVC (or derivatives, MVP / MVVM).

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Gerrit vs Github: for code review and codebase management

Sure, Github wins on the UI. Hands down. But, despite my initial annoyance with Gerrit when I first started using it almost a year ago, I am now a convert. Fully. Let me tell you why.

Note: This is an opinionated (on purpose) piece. I assume your preferences are like mine on certain ideas, such as:

• Fast-forward submits to the target branch are better than allowing merge commits to the target branch. The reason I personally prefer this is that, even if a non-conflicting merge to the target branch is possible, the fact that the review/pull request is not up to date with the latest on the target branch means feature branch test suite runs in the CI pipeline reporting on the review/PR may not be accurate. Another minor point is that forced merge commits are annoying as fuck (opinion) and clutter up Git log histories unnecessarily and I prefer clean histories.
• Atomic/related changes all in one commit is something worth striving for. Having your dev

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var debug = process.env.NODE_ENV !== "production";
var webpack = require('webpack');

module.exports = {
  context: __dirname,
  devtool: debug ? "inline-sourcemap" : null,
  entry: "./js/scripts.js",
  output: {
    path: __dirname + "/js",
    filename: "scripts.min.js"

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Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

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# Companies currently using Go throughout the world

## United States

  * [Google](http://google.com/) - the core Go team work at Google. Most uses of Go at Google are confidential.
    * [Kubernetes](http://kubernetes.io/)
    * The [YouTube](http://youtube.com/) team have released their [MySQL scaling infrastructure](http://vitess.io/) as open source software [1](https://www.youtube.com/watch?v=5yDO-tmIoXY), [2](https://www.youtube.com/watch?v=qATTTSg6zXk), [3](https://www.youtube.com/watch?v=midJ6b1LkA0&sns=gp)
    * dl.google.com is written in Go: [mailing list discussion](https://groups.google.com/forum/?fromgroups=#!topic/golang-nuts/BNUNbKSypE0) / [OSCON slides](http://talks.golang.org/2013/oscon-dl.slide#1)
    * [Flywheel: Google's Data Compression Proxy for the Mobile Web](http://research.google.com/pubs/pub43447.html), [blog post on the rewrite](http://matt-welsh.blogspot.co.uk/2013/08/rewriting-large-production-system-in-go.html)
    * [A lot of scripts that earlier were written in Sawzall](http:

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rails runner "ApplicationController.allow_forgery_protection = false; s = ActionDispatch::Integration::Session.new(Rails.application); s.post('/login', user: {login: 'admin', password: 'password'}); s.get('/my'); puts s.response.body"

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// Finds unused indexes in a mysql database

SELECT
  t.TABLE_SCHEMA,
  t.TABLE_NAME,
  s.INDEX_NAME,
  s.COLUMN_NAME,
  s.SEQ_IN_INDEX,
  ( SELECT MAX(SEQ_IN_INDEX)
    FROM INFORMATION_SCHEMA.STATISTICS s2

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function keepTrying(otherArgs, promise) {
	promise = promise||new Promise();
	
	// try doing the important thing
	
	if(success) {
		promise.resolve(result);
	} else {
		setTimeout(function() {
			keepTrying(otherArgs, promise);