5 Common Docker Questions Answered for Self-Hosters

Docker is the backbone of modern self-hosted application deployment, but if you're just getting started, the terminology and setup can feel overwhelming. Here are straightforward answers to five questions we hear most often.

Question 01: What are the system requirements for Docker?

Docker is intentionally lightweight, so most modern hardware can run it without issue. That said, here's a practical baseline to keep in mind:

On Linux, Docker Engine runs natively and is the most resource-efficient setup. If you're deploying a self-hosted application on a VPS or home server, a Linux environment is almost always the right choice.

Question 02: Can I use Docker in production?

Yes, and millions of teams do. Docker is production-ready and powers everything from indie developer projects to enterprise infrastructure. The key is understanding how to use it responsibly.

For self-hosted applications, Docker is especially well-suited to production use because it provides consistent, reproducible environments. Your app behaves the same on your laptop as it does on your customer's server, which dramatically reduces "it works on my machine" headaches.

For more resilient production deployments, consider pairing Docker with an orchestration tool like Docker Compose (for simpler setups) or Kubernetes (for larger scale). Self Host Pro distributes applications as Docker images, making production deployment straightforward for both you and your customers.

Question 03: What's the difference between a registry and a container?

These two terms get mixed up constantly. Here's a clean way to think about them:

Registry - the warehouse A storage service for Docker images. Docker Hub is the public registry. Self Host Pro provides a private registry so only your customers can pull your application's image.

Container - the running instance A live, isolated process on a machine. A container is what actually runs — it's created from an image that was pulled from a registry.

Think of it like this: a registry holds blueprints (images), and a container is a building constructed from that blueprint. You can build many containers from the same image, on different servers, and they'll all behave consistently.

Question 04: Will Docker run any language?

Essentially, yes. Docker is language-agnostic. If it runs on Linux, it can run in a Docker container. Python, Node.js, Go, Ruby, Rust, Java, PHP, .NET are all well-supported with official base images available on Docker Hub.

This is one of Docker's biggest strengths for self-hosted application developers. You can build your application in whatever stack makes sense for the problem, package it into an image, and your customers don't need to install a runtime, manage dependencies, or worry about version conflicts. Everything your app needs is bundled inside the container.

Multi-language stacks (e.g. a Go API with a Node.js frontend) are handled cleanly using multi-stage builds or Docker Compose, keeping your images lean and your architecture modular.

Question 05: Can I run a container without Docker?

Yes! Docker is the most popular container runtime, but it's not the only one. Alternatives like Podman, containerd, and nerdctl all support the OCI (Open Container Initiative) standard, meaning they can run standard Docker images.

Podman in particular is a popular drop-in alternative on Linux systems, especially in environments where running a system-level daemon (like Docker's) isn't ideal. It's daemonless and can run containers rootlessly, which is a security advantage in some setups.

That said, Docker remains the most beginner-friendly choice with the best tooling ecosystem. For most self-hosting use cases, Docker is the practical default, and it's what Self Host Pro is designed around.

Ready to ship your self-hosted application using Docker? Self Host Pro handles private image distribution, access controls, and customer upgrades — so you can focus on building.