Danny Clarke clarkenciel

Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

Does the design expect failures to happen regularly and handle them gracefully?
Have we kept things as simple as possible?

Reader Macros in Common Lisp

This post also appears on lisper.in.

Reader macros are perhaps not as famous as ordinary macros. While macros are a great way to create your own DSL, reader macros provide even greater flexibility by allowing you to create entirely new syntax on top of Lisp.

Paul Graham explains them very well in [On Lisp][] (Chapter 17, Read-Macros):

The three big moments in a Lisp expression's life are read-time, compile-time, and runtime. Functions are in control at runtime. Macros give us a chance to perform transformations on programs at compile-time. ...read-macros... do their work at read-time.

This is a mix between two sources:

basically the first resource is great but didn't work for me: I had to remove the trailing "/*" in the resource string to make it work. I also noticed that setting the policy on the source bucket was sufficient. In the end these are the exact steps I followed to copy data between two buckets on two accounts

Basically the idea there is:

we allowe the destination account to read the source bucket (in the console for the source account)
we log as the destination and start the copy

Implementing TodoFRP in JavaScript

FRP to me means building your app by transforming values over time, from the input to the current state to the display.

This implementation is based on a the [graphics][1] library and is heavily inspired by [Elm][2]

A full implementation of TodoFRP can be found [online at Raynos/graphics example server][3]

Moving away from MVC

Manage your gmail account in emacs with mu4e

There're a lot of combinations to manage your email with emacs, but this works for me. I've a backup and I can manage my daily email.

The stack:

emacs
offlineimap
mu
mu4e

	package astar

	import "container/heap"

	type NodeQueue []Node

	func NewNodeQueue() NodeQueue {
	return make(NodeQueue, 0, 1000)
	}

	(ns prefix-tree)

	;Record representing a node in the prefix tree.
	;strings: The set of strings that the present node represents
	;edges: Map representing edges emanating from this node.
	;The key being the first letter of the label and the value being the label and the actual node being pointed to."
	(defrecord Node [strings edges])

	(defn shorter-string [a b]
	"Return the shorter string of the two being passed in."

	ּ_בּ
	בּ_בּ
	טּ_טּ
	כּ‗כּ
	לּ_לּ
	מּ_מּ
	סּ_סּ
	תּ_תּ
	٩(×̯×)۶
	٩(̾●̮̮̃̾•̃̾)۶