Couple of Notes After Getting TechCrunched

TechCrunched? Great. Take a cup of coffee and stay awake.
My last side project, got techcrunched on April 5th by John Biggs.
It’s a great thing because of several reasons;

you’ll get lots of feedback instantly, right after you launch your project
first users will be highly interested in Tech and […]


Launched 2 New Projects in February and April

Update: LeFeed featured on techcrunch, please also check John’s article for LeFeed.
And I guess I’ll write a TC effects post soon.

It’s been 2 months since I wrote my rec_sys post, meanwhile, I launched 2 new beta projects, socivid and

Recommender Systems, Collaborative Filtering Approach

tl;dr -> ruby collaborative filtering implementations including Model-Based and SVD Approaches
Getting recommendations is an important part of the decision making. Suggestions for books on Amazon, or movies on Netflix are real- world examples of recommender systems.Design of such recommendation engines depends on the domain and the available data.
Recommender […]


Creating People Groups Using Genetic Algorithm

update: check out for source code.
Genetic Algorithm is great, it is lots of fun to write GA codes.
GA is very useful on optimization problems, but in many cases, you won’t get a huge optimization if you use only GA on a problem (at least that is my […]


Backbone JS – Facebook News Feed Example

update: check out for source code.
Backbone.js is a javascript framework and I just started using backbone along with coffeescript for my new 2 projects.
In this tutorial, I’ll develop a simple backbone javascript application that fetches logged in facebook user’s news feed and lets the user […]


Developing Javascript MVC Application

update: full source code on github:
demo: notebook js mvc application
Recently I needed to create a basic javascript web application that is written with Model-View-Controller Architecture.
There are some good JS tools (MVC-MVVM) that lots of startups and bigger companies use, such as knockout, javascriptmvc.
But if you don’t […]


Twitter Mass Follow App

If you need a starter for twitter API or omniauth gem, take a look at this app. You can find sample usages of changing friendship (follow or unfollow) and using search API of twitter.
Source code:
Demo: Twitter Mass Follow
This basic twitter mass follow/unfollow app has been created for […]


Finding Friends of Friends using Prolog

Here is a *really* simple prolog code snippet to find a list of “friends of friends”.
It is a simple program that uses lists, recursion and database usage for dynamic fact storage.

person = symbol
people_list = symbol*

human(person) %used to store found friend of friend for the goal person

nondeterm has_friend(person, people_list)
nondeterm write_possible_friends(person)
nondeterm is_member(symbol, people_list)
nondeterm check_friends(person, people_list, people_list)
nondeterm find_friends_of_friends(person, person)
nondeterm […] – rails 3.1 open source bookmarking tool

Here is my rails 3.1 learning app,
I used MySQL to store data, will_paginate gem for pagination, configatron gem for custom configuration files, mechanize gem to traverse html of the target webpage’s source file and some others.
I had some difficulties while deploying to my server. My server has CentOS 4 so that causes some […]


Some useful notes on rails 3.1

Here I’ll try to list some useful things that I faced while developing a rails app as a noob.
Ok let’s say you detached your rails server to use the same terminal, but later you need to stop rails server, how? (surprise!)
The solution I found is simply finding Webrick server process id and kill it!

ps -ef […]