Good tech adventures start with some frustration, a need, or a requirement. This is the story of how I simplified the management and access of my local web applications with the help of Traefik and dnsmasq. The reasoning applies just as well for a production server using Docker.

My dev environment is composed of a growing number of web applications self-hosted on my laptop. Such applications include several websites, tools, editors, registries, … They use databases, REST APIs, or more complex backends. Take the example of Supabase, the Docker Compose file includes the Studio, the Kong API gateway, the authentication service, the REST service, the real-time service, the storage service, the meta service, and the PostgreSQL database.

The result is a growing number of containers started on my laptop, accessible at localhost on various ports. Some of them use the default ports and cannot run in parallel to avoid conflicts. For example, the 3000 and 8000 ports are common to a lot of containers present on my machine. To circumvent the issue, some containers use custom ports which I often happen to forget.

The solution is to create local domain names which are easy to remember and use a web proxy to route the requests to the correct container. Traefik helps in the routing and the discovery of those services and dnsmasq provides a custom top-level domain (pseudo-TLD) to access them.

Another usage of Traefik is a production server using multiple Docker Compose files for various websites and