You can easily test UI if you use Selenium (UI test tools), PhantomJS (Headless browser), and nose (Unit testing library).
This article describes how to add Google Authenticator (one of two step authentication system) to SSH service.
This article notes how to communicate JSON formatted data between jQuery Ajax and Python CGI.
This article describes how to prepare production level app running environment, using uWSGI which works on mediating between Python Web application and Web server like nginx.
This article describes how to implement Python unit testing using nose, library which can easily implement unit testing.
Note about how to configure nginx to work with CGI written in Python.
This article describes how to implement user authentication system to Flask. Base program that this article uses is created in [previously posted article](https://blog-en.k3n.link/flask-jquery-ajax-post).
This article describes how to use jQuery Ajax POST request with Flask.
Write down a note about Flask, Python based lightweight Web Application Framework.
To check server availability, build monitoring system using Zabbix + Slack.
If you run e-mail server system by one server, not use redundant setup, you may have risks about can't receive/send e-mails. This article describes how to configure redundant e-mail server to avoid problem.
Describe how to migrate GnuPG.
This article describes how to modify UI from other threads in JavaFX.
Describe how to implement Shell Script that receiving other command's output, reading and computing it line-by-line.
This article describes how to implement Euclidean algorithm, which can find greatest common divisor of two numbers, in C and Java.