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If you’ve spent even a little time exploring containers, chances are you’ve come across Docker. But recently, another name has started showing up in the same conversations: Podman. People ask, “Is Podman replacing Docker?” or “Which one should I learn or use?”
Let’s explore this in a truly under-the-hood, crystal-clear way—just as if I were explaining this to a kid who’s curious about how their video game is being packed and shipped to their friend across the internet.
I’ve been working with container technologies for over a decade now, and I’ve watched the ecosystem grow from scrappy tools to essential infrastructure. So, let’s dive in and truly understand the evolution, the differences, and why Podman even exists.
A Quick Recap – What Are Containers?
Before comparing Docker and Podman, let’s briefly revisit what containers are.
Containers are a way to package your application along with everything it needs to run—like system libraries, runtime, and dependencies—into one tidy box. Unlike virtual machines, containers share the host OS kernel, making them faster and lighter.
This packaging solves the classic “It works on my machine” problem.
You can learn more about containers in our article: Virtualization & Containers – Explained
Docker’s Rise
Docker arrived in 2013 and revolutionized how developers build, ship, and run applications. It made containers more accessible, usable, and standardized.
Behind the scenes, Docker was wrapping around Linux kernel features like:
- Namespaces (for isolation),
- Cgroups (for resource limits),
- And Union file systems (for layering images efficiently).
Docker also introduced a rich CLI, image management, Docker Hub, and Docker daemon (a background service that manages containers).
But as Docker grew, concerns began to surface:
- The monolithic architecture (everything via one central Docker daemon),
- Root-level privileges, posing potential security risks,
- And a desire for modular, daemon-less alternatives.
Enter Podman.
Podman’s Mission
Podman was created by Red Hat as a drop-in replacement for Docker, but with a focus on security, modularity, and daemonless architecture.
It addresses Docker’s pain points with a few major differences:
1. Daemonless Architecture
Docker uses a central Docker daemon that runs as root. This means every container action goes through this single, privileged process.
Podman, on the other hand, is daemonless. It runs containers directly under your user account. Each container is a child process of your shell session—no root-level service required.
– Security win
– Simpler debugging
– Easier automation
2. Rootless Containers
Podman runs containers as non-root users without sacrificing functionality.
This is a major leap forward in terms of sandboxing and isolating environments, especially in shared environments or developer machines.
Docker also supports rootless mode now, but it came later and with more setup complexity.
3. Docker CLI Compatibility
You can replace docker with podman and most commands still work:
docker run -it ubuntu
# can become:
podman run -it ubuntuThis makes migration nearly painless.
4. Pods, Not Just Containers
This is where Podman shines for Kubernetes users. Podman natively supports pods, just like Kubernetes does.
A pod is a group of one or more containers that share network and storage.
With Podman, you can test pod structures locally without needing to spin up a Kubernetes cluster.
This makes it a great development tool if you plan to deploy on Kubernetes.
5. No Central Daemon Means Easier Automation
Since Podman doesn’t need a running daemon, scripting becomes simpler. You don’t have to worry about starting or restarting background services.
Also, it plays well with systemd, so you can manage containers just like any other Linux service.
Which One Should You Use?
Let’s compare them side by side:
| Feature | Docker | Podman |
|---|---|---|
| Daemon Required | Yes | No |
| Rootless Support | Limited (newer feature) | Native |
| Pod Support | No | Yes (native Kubernetes style) |
| CLI Compatibility | Native | Docker-compatible |
| Systemd Integration | No | Yes |
| Docker Compose Support | Native (docker-compose) | Indirect (podman-compose) |
| Kubernetes Integration | Indirect | Native via pods |
| Windows/Mac Support | Full | Limited (Linux-first) |
Under the Hood – What’s Actually Happening?
Docker:
- Uses containerd to manage containers.
- Communicates through its daemon.
- Everything flows through the Docker API.
Podman:
- Uses runc, just like Docker.
- Spawns containers directly from your CLI.
- Stores metadata and image layers in the same standard locations as Docker.
So fundamentally, both use the same building blocks under the Linux hood, but their approach to managing and controlling containers is where they diverge.
Real-World Use Cases
Use Docker if:
- You’re working in environments that rely on Docker Compose.
- You need Windows or macOS support.
- Your CI/CD tools (like Jenkins, GitLab) already depend on the Docker API.
Use Podman if:
- You prioritize security and rootless environments.
- You want to mimic Kubernetes pod structures.
- You prefer daemonless scripting and tighter systemd integration.
Final Thoughts – Not a Battle, But a Choice
Think of Docker and Podman not as competitors, but as tools in your toolbox.
Docker is polished, battle-tested, and widely adopted. Podman is secure, modern, and aligned with how containers will likely evolve, especially in Kubernetes-focused workflows.
As a developer experienced both techs both are amazing in their own way.
