Notes about programming

Make it Secure, GraphQL by Rails

These days, attacks on a web application becomes more and more common. Every web application should be protected to get rid of such attacks. Ruby on Rails provides ways to make it secure out of the box. Additionally, well-used gems in Rails world, such as Devise (, give us convenient ways to protect the Rails app.

Getting Started GraphQL Using Ruby on Rails

GraphQL is an API standard to provide resources on the server-side to various types of clients. GraphQL itself is a specification and doesn’t provide an implementation. For Ruby on Rails, GraphQL Ruby is the most popular library.

Rails App Creation with Options

The easiest way to create a Ruby on Rails app is absolutely to hit the command:

Datomic Quick Start in 2023

I used to use Datomic,, a lot. Datomic is a unique database. The most attractive feature would be the idea of preserving transactions. Based on the transaction id, Datomic is able to pull out the past data which has been already updated later.

Setting Up GCP Instance for Deep Learning

This post is going to be very different from what I write here. The content is a memo how I create a GCP (Google Cloud Platform) instance for Deep Learning. While I study algorithm stuff, I also have been studying Deep Learning. In my early days, I tried to train my Deep Learning model only on a laptop. My laptop is 2012 model MacBook Pro, so I would say it is reasonably fast. However, when it comes to Deep Learning, the training was quite painful on the such machine. Often, I ran the training over night to get a disappointed result. Still, I didn’t use any of pricey cloud environment since it was my personal study unrelated to my day job. I wanted to save money.