Docker vs. Podman vs. Buildah: Which Container Tool Should You Use?

Pros and Cons for Developers and Sysadmins | Security, Performance, and Compatibility Insights

As containerization becomes the standard for modern software development and deployment, choosing the right tool for building, managing, and running containers is crucial. While Docker has long dominated this space, Podman and Buildah have emerged as powerful alternatives—especially for those focused on security, rootless operations, and modular workflows.


In this post, we’ll break down the differences, pros, and cons of Docker, Podman, and Buildah for developers and system administrators, with a focus on:

  • Tool features and architecture

  • Security implications

  • Performance and compatibility

🐳 Docker: The Standard in Containerization


✅ Pros:

  • All-in-one solution for building, running, and managing containers.

  • Huge community and ecosystem (Docker Hub, Compose, Swarm, etc.).

  • Excellent developer experience with CLI and GUI tools.

  • Compatible with nearly every CI/CD and orchestration tool.


❌ Cons:

  • Runs a daemon (dockerd) as root, which poses potential security risks.

  • Monolithic design (build + run + manage tightly coupled).

  • Licensing restrictions on Docker Desktop for enterprise use.


🛡️ Security:

  • Containers run under a daemon, often requiring root access.

  • Namespace isolation is good, but fine-grained control requires effort.

🧊 Podman: The Rootless Alternative


✅ Pros:

  • Daemonless and rootless by design—better security out of the box.

  • CLI is Docker-compatible, making migration easy (alias docker=podman).

  • Integrates well with systemd for service management.

  • Supports pods (like Kubernetes), making it ideal for multi-container apps.


❌ Cons:

  • Smaller community and ecosystem than Docker.

  • GUI tools and orchestration capabilities are still evolving.

  • May require adjustments for developers used to Docker Compose.

🛡️ Security:

  • Runs containers as regular users (rootless), reducing attack surface.

  • SELinux and AppArmor integration supported.

  • Great fit for hardened environments (e.g., STIG compliance).

🔨 Buildah: Focused on Building OCI Images


✅ Pros:

  • Specialized tool for building OCI-compliant images.

  • Works without a daemon, and integrates with Podman.

  • Ideal for secure CI/CD pipelines—builds images as non-root users.

  • Allows granular image construction using low-level commands or Dockerfile.


❌ Cons:

  • Doesn’t manage or run containers—it’s strictly for building.

  • Learning curve if transitioning from docker build to scripting with Buildah.

  • Limited use outside of container building workflows.


🛡️ Security:

  • Supports rootless builds, secure in automated pipelines.

  • Compatible with namespaces and advanced kernel features.

🧩 Docker vs Podman vs Buildah: Feature Comparison


Feature

Docker

Podman

Buildah

Daemon Required

✅ Yes

❌ No

❌ No

Rootless Support

⚠️ Limited

✅ Full

✅ Full

Container Runtime

✅ Yes

✅ Yes

❌ No

Image Building

✅ Yes

✅ Yes

✅ Yes

Dockerfile Support

✅ Yes

✅ Yes

✅ Yes

Kubernetes-Friendly

✅ Yes

✅ Pods

⚠️ Build only

System Integration

❌ Minimal

✅ systemd

⚠️ Limited

Enterprise Security

⚠️ Complex

✅ Simpler

✅ Simpler

🔍 Use Cases


👨‍💻 Developers:

  • Docker is still ideal for fast prototyping, application testing, and local dev.

  • Podman offers a nearly drop-in replacement for Docker with added security.


👨‍🔧 Sysadmins / DevOps:

  • Podman + Buildah combo is a strong choice for secure CI/CD pipelines.

  • Buildah shines in automated environments focused on image creation without running containers.


🛠️ In CI/CD:

  • Use Buildah to create images in GitLab/GitHub Actions without requiring a root daemon.

  • Combine with Podman for testing or deployment in staging.

🔒 Security & Compliance


Security-conscious teams often gravitate towards Podman and Buildah for:

  • Daemonless architecture (no long-running root processes).

  • Better integration with kernel security features.

  • Compliance with enterprise policies and hardening guides.


If security is a top concern, moving away from Docker's root daemon model can significantly reduce risk.

🧱 General Container Runtime Environments

Container runtimes are the low-level components responsible for running containers (e.g. managing namespaces, cgroups, networking, etc.). They often plug into higher-level tools like Docker, Kubernetes, or Podman.


In addition to the 3 CREs mentioned above, the following are some of the most widely used container runtimes today:

✅ 1. containerd

  • 🧱 Core container runtime (used by Docker, Kubernetes, CRI-O)

  • 📦 Maintained by the CNCF (Cloud Native Computing Foundation)

  • 🚀 Works with Kubernetes via the Container Runtime Interface (CRI)

  • 🛠️ CLI: ctr or nerdctl (more Docker-like)

✅ 2. CRI-O

  • 🔍 Kubernetes-native container runtime

  • 🧼 Lightweight and minimal, only supports Kubernetes workloads

  • ❌ Not a general-purpose container tool (no docker build-like features)

  • 🛠️ CLI: crictl

✅ 3. runc

  • 🧱 Low-level runtime for running a single container

  • Used underneath tools like Docker, containerd, Podman

  • Implements the OCI Runtime Spec

  • Not meant for direct use by end users

✅ 4. gVisor (Sandboxed Runtime)

  • 👮 Focuses on security via user-space kernel emulation

  • Slower, but isolates workloads more strictly

  • Used in Google Cloud’s serverless and Kubernetes workloads

✅ 5. Kata Containers

  • 👑 Lightweight virtual machines that behave like containers

  • Offers stronger isolation (hardware-based)

  • Supported in OpenStack, Kubernetes

Other Niche or Experimental Runtimes

  • Firecracker – lightweight VMM by AWS (used in Lambda, Fargate)

  • LXC/LXD – System containers (like VMs but with less overhead)

  • Wasmtime / WasmEdge – WebAssembly-based container-like runtimes

🔄 Quick Comparison Table


Runtime

General Use

Kubernetes

Daemonless

Sandboxed/Secured

Docker

✅

❌ (deprecated)

❌

❌

containerd

✅

✅

❌

❌

CRI-O

❌

✅

✅

❌

Podman

✅

✅ (via CRI-O)

✅

❌

runc

❌ (internal)

✅

✅

❌

gVisor

❌

✅

✅

✅

Kata

✅

✅

✅

✅ (hardware)

Firecracker

❌ (special use)

✅

✅

✅

✅ TL;DR

If you're:

  • Developing locally: Use Docker or Podman

  • Running Kubernetes: Use containerd or CRI-O

  • Need strong isolation: Use Kata or gVisor

  • Want rootless/daemonless: Use Podman