1. Erlang: What, Why and How
COSI Lightning talk by:
Jacob Torrey

2. What is Erlang?
A programming language created by Ericsson for telephony switches.
Many concurrent processes
Must have high uptime
It's been around for quite a while, but is just now getting popular
Buzzwords: Functional, Distributed, Highly- concurrent
Used by: Facebook, CouchDB, ejabberd...
Similar to: Prolog, Haskell...

3. Why Erlang?
It has a VERY lightweight process system (think 2 million per CPU) with:
No locking or shared memory – No nightmares
Pure message passing – Can pass any data in messages
Processes can be on remote machines
Erlang VM can take advantage of new hardware without program changes
Multi-core and multi-processor
Near linear speed up with less than 16 cores!

4. Ok, so How? Erlang requires a VM (http://www.erlang.org)
Windows, OSX, *NIX
Run erl in the command prompt
1> 1. 1
2> A = 1.
B = A + 1. 2

5. Show me the money!... or code
double(Num) →
Num * 2.
doubleList(ListNum) →
F = fun(F) → double(A) end,
lists:map(F, ListNum). OR
rpc:pmap({?MODULE, double}, [], ListNum).

6. What is the advantage
Since you can fork and forget about processes, you can conceptualize problems like in the real world.
No race conditions or other nasties
Erlang will take advantage of multi-cores without your help
Distributed for hardware failover
Functional paradigm, so it rocks! ;)

7. Erlang + COSI = <3
OSP – My project to abstract away server boilerplate code to allow for the simple development of server daemons requiring just the server logic.
Distributed data store for redundance and load balancing
Simple management console
Standard XML servlet format

8. Fin Ideas taken from: Devon Smith's Code4Lib Erlang talk
008.lightningtalk.Erlang