Captain's Log is an application for logging anything you want. The intent is to be able to log anything in relatively free form while still being able to extract and analyze your logs. Think structured logging, but for personal use.
The application is made up of three separate services: a service for entry processing, one for entry querying, and a web application. Note that the web application is itself made up of a web server and a background worker.
There's also a separate data synchronization application that is able to aggregate data from various services and send them to Captain's Log.
Code and documentation for each service can be found in the appropriate
directory and in the docs
directory.