Podman is a developer-facing container tool (replaces Docker CLI). containerd is a container runtime for orchestrators (powers Kubernetes). They serve different layers of the stack.
Architecture
| Aspect | Podman | containerd |
|---|---|---|
| Purpose | Build, run, manage containers (developer tool) | Container runtime (orchestrator backend) |
| Daemon | Daemonless (fork/exec) | Daemon (containerd process) |
| CLI | podman (Docker-compatible) | ctr, nerdctl (Docker-compatible) |
| Rootless | Native (default on Fedora/RHEL) | Supported (requires setup) |
| Pod support | Native (Podman pods) | Via Kubernetes CRI |
| Kubernetes CRI | CRI-O (same OCI ecosystem) | Built-in CRI plugin |
| Build images | podman build (Buildah backend) | Not a builder (use BuildKit) |
| Compose | podman-compose or Docker Compose | nerdctl compose |
| Used by | Developers, RHEL/Fedora users | Kubernetes (EKS, GKE, K3s, Kind) |
When you encounter each
Podman — you are a developer building and running containers on your workstation or server:
# Drop-in Docker replacement
alias docker=podman
podman run -d -p 8080:80 nginx
podman build -t myapp .
podman push myapp:latest registry.example.com/myapp:latest
# Rootless by default — no privilege escalation
podman run --rm -it alpine whoami # runs as your user
# Generate Kubernetes YAML from running containers
podman generate kube my-pod > pod.yaml
# Systemd integration
podman generate systemd --new --name my-container > my-container.servicecontainerd — you are running Kubernetes and containerd is the runtime pulling and running images:
# containerd is typically managed by kubelet, not directly
# But you can interact with it via crictl:
crictl ps
crictl images
crictl pull docker.io/library/nginx:latest
# Or via nerdctl (Docker-compatible CLI for containerd)
nerdctl run -d -p 8080:80 nginx
nerdctl build -t myapp .Rootless containers
| Feature | Podman | containerd |
|---|---|---|
| Default rootless | Yes (Fedora, RHEL 9+) | No (requires manual setup) |
| User namespace | Automatic | Manual UID mapping |
| Network | slirp4netns or pasta | slirp4netns |
| Storage | fuse-overlayfs or native overlay | fuse-overlayfs |
Podman’s rootless experience is seamless — install and run. containerd rootless requires additional configuration.
Kubernetes integration
containerd is the default runtime for most Kubernetes distributions:
| Distribution | Default Runtime |
|---|---|
| EKS | containerd |
| GKE | containerd |
| AKS | containerd |
| K3s | containerd |
| Kind | containerd |
| OpenShift | CRI-O (Podman ecosystem) |
| Minikube | containerd (or Docker) |
Podman does not run inside Kubernetes — CRI-O does (same OCI ecosystem, same image format, both Red Hat projects).
Decision guide
Choose Podman when:
- Developer workstation — building, testing, running containers locally
- Rootless containers — security requirement, no root daemon
- RHEL/Fedora ecosystem — Podman is the default, Docker is not shipped
- Docker replacement — alias
docker=podman, same commands - Systemd integration — generate unit files from containers
- Podman pods — group containers without Kubernetes
Choose containerd when:
- Kubernetes runtime — kubelet needs a CRI-compatible runtime
- Lightweight daemon — less overhead than Docker Engine
- CI/CD builders — BuildKit on containerd for image builds
- K3s, Kind, managed Kubernetes — containerd is already there
They are complementary
Most production setups use both: Podman on developer laptops, containerd inside Kubernetes. They share the same OCI image format — images built with Podman run on containerd and vice versa.
