Open-source alternatives to Coreos Rkt

crun is a low-level container runtime that implements the Open Container Initiative specification for managing the lifecycle of isolated processes. It provides the core mechanisms for container creation, execution, and deletion, ensuring compatibility across platforms through standardized lifecycle management. The project distinguishes itself by offering a shared C library that allows container runtime operations to be embedded directly into other compiled applications. It further extends execution capabilities through specialized handlers that enable the deployment of containers within isola

Moby is an OCI container engine and runtime manager designed for building, running, and managing isolated containers based on Open Container Initiative standards. It functions as a container daemon and image builder, providing a core engine to orchestrate the full lifecycle of containers and the packaging of source code into portable images. The project provides a standardized HTTP interface that allows for programmatic container management, enabling external clients to control daemon settings and container operations. It supports a rootless security model, allowing the engine daemon to execu

Pouch is a Linux container runtime and OCI container engine designed to execute containerized applications. It functions as a Kubernetes container runtime, integrating with orchestrators to manage the lifecycle of pods and isolated application environments. The project features a peer-to-peer image distribution system to deliver large container images across large-scale clusters while reducing bandwidth load. It also provides support for legacy Linux kernel versions, allowing modern container runtimes to maintain compatibility with older hardware. The runtime implements application isolation

Docker CE is an OCI compliant container platform and runtime engine used for building and running applications within isolated environments. It functions as a Linux container orchestrator and provides a command-line interface to manage the entire lifecycle of running application instances. The platform enables containerized application deployment and cross-platform software distribution by packaging software with its dependencies. It supports microservices architecture management and the creation of reproducible local development environments. The system includes capabilities for application

CRI-O is an open-source container runtime that implements the Kubernetes Container Runtime Interface (CRI) to manage container images, pods, and containers on cluster nodes using OCI-compatible runtimes. It serves as a node-level container manager that handles image pulling, container lifecycle, and resource monitoring for Kubernetes clusters, running containers according to the Open Container Initiative specifications. The runtime distinguishes itself through live configuration reloading that applies changes to runtime definitions, registry mirrors, and TLS certificates without restarting th

Incus is a unified orchestration platform for managing system containers, OCI application containers, and virtual machines through a single control plane. It brings together cluster infrastructure management, secure multi-tenancy, software-defined networking, and pluggable storage backend orchestration into one cohesive system exposed via a full REST API and command-line interface. What distinguishes Incus is its ability to run multiple instance types side by side—full Linux system containers, OCI application containers, and QEMU virtual machines—all managed with consistent tooling. Networkin

This is an educational repository that teaches container orchestration fundamentals through hands-on guides and practical examples. It covers core Kubernetes concepts including Pods, Services, Deployments, and Namespaces, providing step-by-step exercises that demonstrate how to manage containerized applications across a cluster. The tutorials walk through essential Kubernetes capabilities such as decoupling configuration from application code using ConfigMaps and Secrets, exposing Pods with stable network endpoints via Services, and routing external traffic with Ingress controllers. The mater

This project is a Docker educational resource and a collection of practical examples designed for learning containerization technologies. It serves as a guide for understanding container fundamentals, including the creation and management of custom images and the use of registries. The repository provides specialized references for container security hardening, such as managing kernel privileges and implementing supply chain security. It also includes tutorials for multi-container orchestration and a DevOps guide focused on CI/CD automation and image optimization. The material covers a broad

Finch is a virtual machine-based container runtime and OCI container management CLI used for local container development. It operates by running container workloads inside a background virtual machine to isolate them from the host operating system. The project serves as an OCI image builder and a multi-container service orchestrator for simulating complex production environments on a workstation. The runtime functions as a cross-platform container engine, utilizing emulation layers to execute container images built for foreign CPU architectures. It distinguishes its image distribution through

Libpod is a container management library for running and controlling the lifecycle of Open Container Initiative compliant containers and images across different storage backends. It provides a programmatic interface for the remote control and automation of container environments. The project enables the coordination of multiple containers into pods that share network namespaces and other shared resources. It supports rootless container execution by using user namespaces to launch containers without administrative privileges. The library covers a broad range of system operations, including im

LXC is an OS-level virtualization framework and Linux container manager used to run multiple isolated Linux systems on a single host. It functions as a kernel namespace orchestrator and unprivileged container runtime, allowing for the creation and management of system containers without the overhead of a hypervisor. The project provides unprivileged container execution by mapping container root users to unprivileged host users to prevent host system access. It ensures security through system call filtering and root user isolation, enabling containers to run without requiring host root privile

Youki is an OCI container runtime written in Rust. It implements the Open Container Initiative runtime specification to manage the lifecycle of containerized processes and ensure compatibility with standard container images and engines. The runtime is designed for memory safety and supports rootless container execution, allowing containers to run as non-root users to reduce security risks and limit privilege escalation. It provides core container management capabilities, including spawning and managing OCI containers. This is achieved through Linux namespace isolation, cgroup-based resource

Containerd is a daemon-based container runtime that manages the complete lifecycle of containers on a host system. It functions as a core orchestration backend, handling image distribution, storage, and process execution while adhering to industry-standard specifications for container execution and configuration. The project is distinguished by its modular, plugin-based architecture, which allows for the extension of storage, runtime, and networking capabilities without requiring a full daemon recompile. It utilizes a shim-based execution model to delegate low-level operations, ensuring isola

Buildkit is a programmable container build toolkit and OCI container image builder that converts build definitions into concurrent dependency graphs for image construction. It functions as an OCI image distribution engine, capable of generating container images and exporting artifacts to local storage or remote registries. The project is distinguished by its use of a low-level binary intermediate representation to decouple high-level build languages from the execution engine. It supports multi-platform image builds through user-mode architecture emulation and provides a distributed build cach

Kata Containers is an OCI container runtime that launches containers inside lightweight virtual machines to combine hardware-level isolation with container operational speed. It functions as a hardware-isolated container engine and lightweight VM hypervisor, providing a virtual machine monitor interface that abstracts multiple hypervisors to optimize for performance or specific hardware emulation. The project distinguishes itself through a confidential computing runtime that leverages hardware-backed trusted execution environments, such as Intel TDX and AMD SEV-SNP, to protect data in use. It

This project is a collection of curated and standardized Docker base images that serve as reliable starting points for building containerized applications. It functions as an OCI container image repository and a build template library, providing a central source of truth for images that adhere to Open Container Initiative standards for portability. The project utilizes an automated image lifecycle pipeline to build, tag, and push images, ensuring that dependencies remain current and security patches are applied. It specifically supports cross-platform distribution by providing a multi-archite

Docker is an OCI container engine and runtime orchestrator used to build, run, and manage isolated applications. It functions as a container image builder for creating portable snapshots of applications and a registry manager for storing, versioning, and distributing those images across environments. The platform provides a centralized daemon to control the creation, execution, and termination of containerized workloads. It allows for the assembly of modular container systems by combining build tools, registries, and runtimes. Its core capabilities cover container image creation, registry ad

LXD is a system container manager and virtual machine manager that provides a unified interface for running full Linux systems. It acts as a container cluster orchestrator, an image format converter, and an infrastructure manager that exposes control through a REST API and language-specific SDKs. The project distinguishes itself by providing a unified container and virtual machine abstraction, treating both as generic instances within a single management layer. It supports distributed cluster coordination to synchronize state and distribute workloads across multiple physical nodes. The syste

This project is an OCI-compatible container runtime that executes workloads within lightweight virtual machines. By leveraging hardware-based virtualization, it provides strong security isolation between containerized processes and the host operating system, serving as a drop-in replacement for traditional container execution environments. The runtime distinguishes itself through a hypervisor-agnostic architecture that abstracts underlying virtualization operations, allowing for consistent container lifecycle management across different backends. It integrates directly with standard container

This project is a secure container runtime that provides strong isolation for application workloads by implementing a userspace kernel. By intercepting system calls and executing them within a memory-safe, restricted environment, it minimizes the attack surface exposed to the host kernel. It functions as a drop-in engine for standard container orchestration platforms, ensuring compatibility with industry-standard runtime specifications while maintaining a hardened execution boundary. The runtime distinguishes itself through its ability to virtualize core system resources, including an indepen

Falco is an eBPF runtime security monitor and cloud native detection engine that identifies abnormal behavior and security threats across hosts and containers. It functions as a Linux kernel event auditor, capturing system calls and kernel events in real-time to detect malicious activity. The system distinguishes itself through a rule-based threat detection model that evaluates system activity against a library of community-maintained rules and custom security definitions. It enriches raw kernel events with container and Kubernetes metadata to provide observability into isolated environments

This project provides strategic roadmaps and guides detailing the evolution and deployment patterns of managed container orchestration and security services. It serves as a public tracking document for upcoming features and development priorities for EKS, ECS, ECR, and Fargate. The resource includes a cloud container orchestration guide and a Kubernetes and ECS strategy, outlining the development of managed Kubernetes and proprietary orchestration services for cloud infrastructure. It also provides a security and monitoring plan focused on scanning malicious activity and tracking workload hea

Sysdig is a Linux system observability tool and kernel event analyzer designed for capturing and analyzing kernel-level system calls and operating system events. It functions as a system call tracer and container security monitor, providing deep visibility into the activity of machines, virtual machines, and containers. The project specializes in non-invasive container inspection, allowing for the monitoring of container activity and resource usage without modifying the container environment or adding instrumentation. It enables the recording of detailed system traces into binary files for re

Buildah is a tool for creating OCI-compliant container images without requiring a background daemon process. It functions as a daemonless image constructor and distribution tool, allowing users to build, push, and pull images between local storage and remote registries. The project distinguishes itself by supporting unprivileged image building through the use of user namespaces and rootless mode. It enables direct modification of container root filesystems by mounting them to the host, allowing images to be treated as directories that can be manipulated via standard shell commands or scripts.

This project is a security compliance tool and configuration auditor designed to evaluate Docker deployments against industry security benchmarks. It functions as a script-based scanner that identifies misconfigurations and vulnerabilities within both the host operating system and container settings. The tool specifically implements the Center for Internet Security standards for Docker to verify host and container configurations. It enables a hardening workflow by comparing system states against these standards to identify security gaps and document compliance status. The audit engine suppor

The CNCF Curriculum is an open-source repository that organizes exam domains and learning paths for CNCF certification courses covering Kubernetes and cloud-native technologies. It structures certification content into weighted domains that reflect exam question distribution, providing a structured study guide for candidates preparing for CNCF certifications. The curriculum is organized around multiple cloud-native domains including networking, security, GitOps, platform engineering, and certification preparation. It teaches cloud-native concepts through the lens of building and operating int

This project is a comprehensive collection of tutorials and guided laboratories designed to teach containerization, networking, and security using Docker. It serves as a learning path for building portable images and executing isolated processes. The materials provide specific guides for managing container clusters and scaling services through Docker Swarm and overlay networks. It includes a security handbook for implementing image scanning and secret management, as well as laboratories dedicated to modernizing legacy applications by wrapping older software installers into containers. The co