Container Runtime

Meet Box

A lightweight OCI-compatible container runtime and image manager written in Go. Build, run, and distribute containers with Linux namespace isolation, cgroup resource control, and zero daemon requirements.

# Run a container with Koder Box
$ kbox run -d --name web \
  -p 8080:80 \
  -v ./app:/usr/share/nginx/html \
  nginx:alpine

# Container started in 38ms
# Memory: 4.2 MB RSS
# PID: 29451 (no daemon)

Features

Everything you need, built from the ground up.

Daemonless Architecture

No background daemon required. Each container runs as a direct child process, simplifying debugging, logging, and resource accounting.

OCI Compliant

Fully compatible with OCI image and runtime specs. Pull from Docker Hub, GHCR, or any OCI registry without conversion.

Native Performance

Written in Go with a minimal footprint. Native Linux namespaces and cgroup v1/v2 integration deliver fast container starts with predictable resource limits.

Rootless by Default

Run containers as unprivileged users out of the box with user namespace mapping, no suid binaries, and full seccomp/AppArmor profiles.

🔒
Built-in Image Builder

Dockerfile-compatible build engine with layer caching, multi-stage builds, and BuildKit-style cache mounts — no separate buildx plugin needed.

Composable Stacks

Define multi-container stacks with a simple YAML format compatible with Docker Compose files. Network, volume, and dependency management included.

💾
Snapshot Filesystem

Copy-on-write filesystem using overlayfs or native btrfs/zfs snapshots for instant container cloning and efficient disk usage.

📈
GPU Passthrough

First-class NVIDIA and AMD GPU support for AI/ML workloads with automatic device mapping and driver injection.

💻
Registry Server

Built-in lightweight OCI registry for air-gapped environments and local development — no external dependencies.

📦
Checkpoint & Restore

CRIU-based live migration and checkpoint/restore for stateful containers with near-zero downtime.

Build Images Fast

Dockerfile-compatible builds with intelligent layer caching and parallel stage execution.

  • Multi-stage builds with shared cache
  • BuildKit-compatible cache mounts
  • Parallel layer downloads and extraction
# Build with layer caching
$ kbox build -t myapp:latest .

# Step 1/8: FROM node:20-alpine
# Step 2/8: COPY package*.json ./
#  -> Using cache (hit)
# Built in 2.1s (7 layers cached)

Compose Stacks

Manage multi-container applications with a familiar YAML syntax, fully compatible with Docker Compose.

  • Drop-in replacement for docker-compose
  • Automatic network creation and DNS
  • Health checks and dependency ordering
# stack.yml
services:
  api:
    image: myapp:latest
    ports: ["3000:3000"]
  db:
    image: postgres:16
    volumes: ["pgdata:/var/lib/postgresql/data"]

Registry & Distribution

Built-in OCI registry for local development and air-gapped deployments.

  • Start a local registry with one command
  • Mirror and cache upstream registries
  • Image signing with cosign/notation
# Start local registry
$ kbox registry start --port 5000

# Push image
$ kbox push localhost:5000/myapp:v1

# Sign image
$ kbox sign localhost:5000/myapp:v1

How It Compares

See how Koder Box stacks up against the competition.

FeatureKoder BoxDockerPodmancontainerdLXC
Daemonless architecture
Rootless by defaultPartialPartial
OCI image compatible
Built-in image builder
Built-in compose
Built-in registry
GPU passthrough
Sub-50ms start time

Frequently Asked Questions

For most workflows, yes. Koder Box supports the same CLI commands, Dockerfile syntax, and Compose files. You can alias 'docker' to 'kbox' and existing scripts will work without modification.

Yes. Koder Box implements the CRI (Container Runtime Interface) and can serve as the container runtime for kubelet, replacing containerd or CRI-O in any Kubernetes cluster.

Go provides an excellent balance of performance, safety, and ecosystem maturity for systems programming. Koder Box compiles to a single static binary under 15 MB with CGO disabled — easy to deploy and redistribute on any Linux distribution.

Absolutely. Koder Box pulls from any OCI-compliant registry including Docker Hub, GitHub Container Registry, Amazon ECR, Google Artifact Registry, and private registries.

Yes. Rootless mode is the default and recommended configuration. It uses user namespaces, slirp4netns for networking, and fuse-overlayfs for storage — all battle-tested in production environments.

Ready to get started?

Containers Without the Overhead