Rails + Sidekiq + PostgreSQL + Redis (Docker)
An example of how to use docker and docker-compose for a Rails application with Sidekiq, Redis and PostgreSQL.
HAProxy + PostgreSQL (Docker)
An example of how to run PostgreSQL database master and slaves with streaming replication and with HAProxy to load balance connections over them.
This project illustrates how you can easily add a trendline to HighCharts charts.