Introduction

Building web apps with continuation Monads

Introduction of DWANGO, Niconico, and account system
Problems of component technologies of existing web frameworks
Constructing web applications using continuation monads
Updating components using continuation monads

Introducting DWANGO and Niconico

DWANGO company that operates video sharing
Niconico has 50 million accounts
Most major streaming service in Japan

FP in DWANGO

Dwango has adopted FP
Using variety of languages
- Scala
- Erlang
Speaker joined as scala specialist
Wrote github.com/dwango/scala_text

Account System

Variety of services in Dwango
- e-books
- Slide services
- video /live streaming
User info is aggregated in account system across platforms
Tasks
- registration
- authentication
- updating user info
Required interfaces
- Want component tech to decompose application
- doFilter
- Servlet Request
- Servlet Response
- FilterChain -(Speaker gave examples here) #Problems with Component Technologies
Filter method doesn't have much info on type and parameters
Don't necessarily know what kind of parameters will be passed

Introduciing continuation monads

Continuation represents rest o computation at any given point int he execution
A: Given point. R: Result. a -> r: Remainder of function (?)

More specific information found here: http://www.haskellforall.com/2012/12/the-continuation-monad.html

##Stray notes

Index continuation monad
- Can combine comp monads with different return types