Qcker

A daemonless, rootless container engine written in Rust

Qcker is a lightweight, high-performance alternative to Docker.
No daemon. No bloat. Just containers.

Production by PaongLabs

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What's New in v1.1

• Real MicroVM Backend: Full implementation with vsock host-guest communication, container lifecycle management (create/start/kill/delete), exec support, file operations via vsock, and automatic VM startup
• vsock Protocol: Length-prefixed JSON protocol over vsock for zero-overhead host-guest communication with ping/pong health checks and timeout handling
• Enhanced VmmManager: QEMU process management with serial console logging, KVM detection, version query, and graceful shutdown
• Dracula Theme System: Centralized theme.rs with full Dracula color palette, status colors, gauge colors, semantic style helpers, and 20+ pre-built style functions
• Zero Compiler Warnings: All Rust snake_case, dead_code, unused_import, and clippy warnings resolved across the entire workspace
• Improved Error Handling: All error constructors now follow Rust naming conventions (snake_case)
• TUI Refinements: Status bar uses darker background for visual separation, marketplace uses semantic status colors
• Cleaner Codebase: Removed unused imports, dead code annotated, proper variable scoping

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TUI Demo

The TUI provides a visual dashboard for managing containers, browsing files, editing configs, and managing extensions with mouse support and auto-refresh.

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Quick Start

Build from source

git clone https://github.com/farhanturu/qcker.git
cd qcker
cargo build --release

Run a container

# Simple command
sudo ./target/release/qcker run --rootfs /path/to/rootfs -- /bin/echo "Hello"

# Interactive shell
sudo ./target/release/qcker run --rootfs /path/to/rootfs -t -- /bin/sh

# With resource limits
sudo ./target/release/qcker run --rootfs /path/to/rootfs \
    --cpus 2 --memory 512 --pids-limit 256 \
    -- /bin/sh

# With GPU
sudo ./target/release/qcker run --rootfs /path/to/rootfs \
    --gpu --vram 1024 \
    -- /bin/sh

Open TUI

./target/release/qcker

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Features

Container Management

• Create, start, stop, kill, delete containers
• List running and stopped containers
• Execute commands inside running containers
• Container logs and state inspection
• Real-time stats (CPU, memory, PIDs)

Resource Limits

• --cpus <cores> - CPU cores (e.g., 1.5)
• --memory <MB> - Memory limit
• --pids-limit <n> - Max processes
• --gpu - Enable GPU access
• --vram <MB> - VRAM limit

Security

• Rootless by default
• PID, network, mount, UTS, IPC, cgroup namespace isolation
• Seccomp syscall filtering (BPF-based)
• Capability dropping (all caps removed by default)
• pivot_root container isolation (not chroot)
• Path traversal protection in tar extraction
• Cryptographic ID generation with getrandom

Error Handling

• Unique error codes (Q-C001, Q-I001, etc.)
• Source location tracking
• Suggestions for fixing errors
• JSON output for scripting
• Retryable error detection

TUI (Terminal UI)

• 7 tabs: Containers, Images, Networks, Volumes, Stats, Logs, Extensions
• Browse and edit files inside containers
• Real-time stats with CPU/memory bars
• Dracula-inspired dark theme with semantic color system
• Mouse support (click, scroll)
• Auto-refresh
• Container actions (stop, kill, delete) from TUI
• Vim-style navigation (j/k)

Docker-Compatible CLI

• qcker run, qcker ps, qcker images, qcker build, qcker exec
• qcker network, qcker volume, qcker compose, qcker extension
• qcker stats, qcker logs, qcker stop
• qcker system info/prune

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CLI Commands

Command	Description
qcker run	Run a container
qcker create	Create a container
qcker start	Start a container
qcker stop	Stop a container
qcker kill	Kill a container
qcker delete	Delete a container
qcker ps	List containers
qcker exec	Execute in container
qcker images	List images
qcker build	Build from Dockerfile
qcker pull	Pull image from registry
qcker logs	View container logs
qcker stats	View container stats
qcker network	Manage networks
qcker volume	Manage volumes
qcker compose	Manage compose apps
qcker extension	Manage extensions
qcker system	System info and prune

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Architecture

qcker/
├── crates/
│   ├── qcker-cli/          # CLI binary + TUI
│   ├── qcker-runtime/      # OCI runtime (namespaces, cgroups, seccomp)
│   ├── qcker-backend/      # Runtime backend (native, MicroVM)
│   ├── qcker-engine/       # Image, build, network, volume, compose, extension
│   ├── qcker-common/       # Shared utilities
│   ├── qcker-error/        # Error library with codes and suggestions
│   └── qcker-ext-api/      # Extension SDK
└── target/release/qcker    # Single binary (~7 MB)

Runtime Backends

Backend	Platform	Description
NativeBackend	Linux	Direct namespace/cgroup usage
MicroVmBackend	macOS/Windows	QEMU-based MicroVM

Backend selection is automatic based on platform.

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MicroVM Support

Qcker includes a real MicroVM backend for running containers on macOS and Windows without a full Docker Desktop installation.

How it works:

• On Linux: Uses native namespaces and cgroups (no VM needed)
• On macOS/Windows: Spawns a minimal MicroVM via QEMU (qemu-system-x86_64 -machine microvm)
• The MicroVM runs a guest agent that listens on vsock port 7421
• Host sends commands via vsock (length-prefixed JSON protocol)
• Container lifecycle: create → start → kill → delete (all via vsock)
• File operations: read/write/list/delete via exec through vsock
• Stats collection: CPU, memory, network, PIDs from guest agent
• Port forwarding: host ports mapped to guest VM ports
• Lazy VM startup: VM starts on first container creation
• Auto-shutdown on backend shutdown with graceful guest agent notification

Protocol:

Host → VM (HostToVm):
  ping | container.create | container.start | container.kill
  container.delete | container.exec | container.stats | vm.shutdown

VM → Host (VmToHost):
  vm.ready | pong | container.created | container.started
  container.exited | container.stats | container.log | error

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Extensions

Browse and manage extensions in the TUI Extensions tab.

Extension	Category	Status
bridge	network	Built-in
overlayfs	storage	Built-in
trivy	security	Available
cilium	network	Available
zfs	storage	Available
loki	logging	Available
buildkit	build	Available

Request new extensions: https://github.com/farhanturu/qcker-extensions/issues

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Comparison

Feature	Docker	Podman	Qcker
Daemon	Yes	No	No
Rootless	Optional	Yes	Yes
Language	Go	Go	Rust
Binary size	200 MB	100 MB	~7 MB
TUI	No	No	Yes
GPU support	Manual	Manual	Built-in
Extensions	Limited	Limited	Full SDK
Error codes	No	No	Yes
MicroVM	No	No	Yes

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Requirements

• Linux kernel 5.3+ (for native backend)
• QEMU (for MicroVM backend on macOS/Windows)
• Rust 1.70+ (for building)

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Build

cargo build --release    # Release build
cargo test               # Run tests
cargo clippy             # Lint

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License

Apache License 2.0 - see LICENSE

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Author

PaongLabs

• GitHub: https://github.com/farhanturu
• Email: paongtech@gmail.com