Tech and Startup War Stories by Team PerfectLine

Every once in a while we write articles about startups (our own or the ones we work with), technical (Ruby on Rails, JavaScript, etc) solutions we’ve created and everything else that comes to our minds.


Correct PayPal IPN handling with Rails

While working with different PayPal payment APIs, I have read a lot of tutorials, library code and documentation about the given matter. While there are several quite competent…

Advisory locking with ActiveRecord

Not too long ago we had a problem with doing (almost) guaranteed inserts for columns with unique constraints on them (see this post). Today I was facing a…

Building Rails 3 custom validators

Actually this post is not so much about just building custom validators for Rails 3 but more like a in-depth introduction to how validations work in the old…