Dylan Vassallo dylanvee

A composable pattern for pure state machines with effects

State machines are everywhere in interactive systems, but they're rarely defined clearly and explicitly. Given some big blob of code including implicit state machines, which transitions are possible and under what conditions? What effects take place on what transitions?

There are existing design patterns for state machines, but all the patterns I've seen complect side effects with the structure of the state machine itself. Instances of these patterns are difficult to test without mocking, and they end up with more dependencies. Worse, the classic patterns compose poorly: hierarchical state machines are typically not straightforward extensions. The functional programming world has solutions, but they don't transpose neatly enough to be broadly usable in mainstream languages.

Here I present a composable pattern for pure state machiness with effects,

General key themes:

Hiring is really hard. You’re not just hiring a “Rails Engineer” or a “Python Programmer” you’re hiring someone who can help you change the world. Tell them why! Talk about the hard problems you’re solving. 2/3 of these talks give ideas and insight into hiring from sourcing to actual interview processes.
Rewriting systems is hard. People think they are going to replace their broken down horse and buggie with a bullet train and this often ends up in disaster. Successful rewrites require an incremental approach that takes months/years and often runs way over schedule. 2/3 of these talks go over how to handle rewrites not only from a high level technical perspective but a cultural/management perspective as well.

Two Developers, Many Lines of Code, and A Campaign that Made History

Harper Reed (CTO of Obama for America, now CEO of Modest) and Dylan Richard (Director of Eng of Obama for America, now CTO of Modest)

http://vimeo.com/104052532

2015-01-29 Unofficial Relay FAQ

Compilation of questions and answers about Relay from React.js Conf.

Disclaimer: I work on Relay at Facebook. Relay is a complex system on which we're iterating aggressively. I'll do my best here to provide accurate, useful answers, but the details are subject to change. I may also be wrong. Feedback and additional questions are welcome.

What is Relay?

Relay is a new framework from Facebook that provides data-fetching functionality for React applications. It was announced at React.js Conf (January 2015).

Please see https://github.com/Mikayex/transmission

How to use

See my blog post.

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

	#!/usr/bin/env python2.7

	try:
	import simplejson as json
	except ImportError:
	import json

	import tempfile
	import sqlite3
	import subprocess

	// make sure you npm install 'url' (the browserify port of the node api url module)
	var url = require('url')
	var Faye = require('faye/browser/faye-browser')

	var API_URL = 'http://localhost:8000/faye'

	// initialise fake window.location - same origin as api host
	// required to use some faye transports which expect to deal with same-origin policy.
	// url.parse return value looks kind of like window.location, if you squint just right
	window.location = url.parse(API_URL)

	// List out each domain's colors theme
	@mathDomainColor: #297395; // The dark blue
	@mathSubjectColor: #30a7de; // The lighter blue
	... more colors ...

	@scienceDomainColor: #ba3d66; // The dark pink
	@scienceSubjectColor: #c8547c; // The lighter pink
	... more colors ...

	// Here's a mixin that will call .domainRuleToApply on each domain for us

	void
	_wrap_add_torrent_params_name_get(void *swig_v)
	{
	libtorrent::add_torrent_params arg1 = (libtorrent::add_torrent_params ) 0 ;
	std::string *result = 0 ;

	struct swigargs {
	libtorrent::add_torrent_params *arg1;
	long : 0;
	_gostring_ result;

	import db_util
	db_util.enable_db_protobuf_projection()
	db_util.enable_ndb_protobuf_projection()