Youki
youki is an open source container runtime written in Rust that implements the OCI runtime specification as a memory-safe alternative to runc, with rootless container support, cgroups v1 and v2, seccomp filtering, and systemd integration. Maintained as a CNCF sandbox project under the youki-dev organization, youki is adopted by container engines such as containerd, Podman, and Docker for executing OCI-compliant workloads.
Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.
API Evangelist profiles Youki the way a machine reads it — 101 machine-readable artifacts across 2 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.
Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Youki scores 45.7/100 (developing), with a separate agent-readiness read of 7/100 (human only). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.
Kin Score
This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.
Kin Score
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Youki
Each block below is one kind of artifact we hold for Youki. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.
APIs 2
Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.
Individual APIs this provider publishes, each with its own machine-readable definition.
Youki Container Runtime
youki is a container runtime written in Rust that implements the OCI runtime specification, providing a memory-safe and high-performance alternative to runc. It supports rootles...
OCI Spec for Rust
oci-spec-rs is a Rust implementation of the OCI Runtime, Image, and Distribution Specifications, providing the data structures and types consumed by youki and other Rust-based c...
Pricing Plans 1
Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.
Published pricing tiers and plan structures.
Youki Plans Pricing
PLANSRate Limits 1
Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.
Documented rate limits and quota policies.
Youki Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.
Cost, billing, and metering signals for API financial operations.
Youki Finops
FINOPSFeatures 9
The notable capabilities this provider advertises, captured as structured features so they can be searched and compared instead of read one landing page at a time.
Notable capabilities this provider offers.
OCI Runtime Spec Compliance
Implements the Open Container Initiative (OCI) runtime specification, allowing youki to run any OCI-compliant container alongside or in place of runc.
Memory-Safe Rust Implementation
Written entirely in Rust to deliver memory safety and stronger isolation guarantees than C-based container runtimes.
Rootless Containers
Enables running containers without root privileges to reduce host attack surface for development and multi-tenant scenarios.
Cgroups v1 and v2 Support
Supports both legacy cgroups v1 and modern cgroups v2 hierarchies for resource management on Linux.
Seccomp Filtering
Applies seccomp BPF filters to restrict syscalls available to containers and harden the runtime surface.
Systemd Integration
Integrates with systemd as a cgroup manager and supports systemd-managed container processes.
Linux Namespaces and Capabilities
Manages mount, UTS, IPC, user, PID, network, and cgroup namespaces and supports capabilities such as CAP_BPF, CAP_PERFMON, and CAP_CHECKPOINT_RESTORE.
Performance
Benchmarks show youki performing roughly twice as fast as runc for container create-to-delete cycles.
CNCF Sandbox Project
Maintained as a Cloud Native Computing Foundation sandbox project with open governance, public roadmap, and community contributors.
Scroll within the panel for all 9 ·
Semantic Vocabularies 2
JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.
JSON-LD contexts and semantic vocabularies used across these APIs.
Youki Oci Image Context
JSON-LDYouki Oci Runtime Context
JSON-LDSpectral Rules 1
Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.
Youki API Rules
SPECTRALJSON Schema 23
Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.
Standalone JSON Schema definitions for this provider's data models.
Oci Image Config
JSON SCHEMAOci Image Content Descriptor
JSON SCHEMAOci Image Defs Descriptor
JSON SCHEMAOci Image Defs
JSON SCHEMAOci Image Index
JSON SCHEMAOci Image Layout
JSON SCHEMAOci Image Manifest
JSON SCHEMAOci Runtime Config Freebsd
JSON SCHEMAOci Runtime Config Linux
JSON SCHEMAOci Runtime Config
JSON SCHEMAOci Runtime Config Solaris
JSON SCHEMAOci Runtime Config Vm
JSON SCHEMAOci Runtime Config Windows
JSON SCHEMAOci Runtime Config Zos
JSON SCHEMAOci Runtime Defs Freebsd
JSON SCHEMAOci Runtime Defs Linux
JSON SCHEMAOci Runtime Defs Vm
JSON SCHEMAOci Runtime Defs Windows
JSON SCHEMAOci Runtime Defs Zos
JSON SCHEMAOci Runtime Defs
JSON SCHEMAOci Runtime Features Linux
JSON SCHEMAOci Runtime Features
JSON SCHEMAOci Runtime State
JSON SCHEMAScroll within the panel for all 23 ·
JSON Structure 23
JSON Structure captures the data shapes in a form built for tooling — a complement to JSON Schema that keeps the model machine-legible.
JSON Structure definitions describing this provider's data shapes.
Oci Image Config Structure
JSON STRUCTUREOci Image Content Descriptor Structure
JSON STRUCTUREOci Image Defs Descriptor Structure
JSON STRUCTUREOci Image Defs Structure
JSON STRUCTUREOci Image Index Structure
JSON STRUCTUREOci Image Layout Structure
JSON STRUCTUREOci Image Manifest Structure
JSON STRUCTUREOci Runtime Config Freebsd Structure
JSON STRUCTUREOci Runtime Config Linux Structure
JSON STRUCTUREOci Runtime Config Solaris Structure
JSON STRUCTUREOci Runtime Config Structure
JSON STRUCTUREOci Runtime Config Vm Structure
JSON STRUCTUREOci Runtime Config Windows Structure
JSON STRUCTUREOci Runtime Config Zos Structure
JSON STRUCTUREOci Runtime Defs Freebsd Structure
JSON STRUCTUREOci Runtime Defs Linux Structure
JSON STRUCTUREOci Runtime Defs Structure
JSON STRUCTUREOci Runtime Defs Vm Structure
JSON STRUCTUREOci Runtime Defs Windows Structure
JSON STRUCTUREOci Runtime Defs Zos Structure
JSON STRUCTUREOci Runtime Features Linux Structure
JSON STRUCTUREOci Runtime Features Structure
JSON STRUCTUREOci Runtime State Structure
JSON STRUCTUREScroll within the panel for all 23 ·
Examples 23
Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.
Example request and response payloads for these APIs.
Oci Image Config Example
EXAMPLEOci Image Defs Example
EXAMPLEOci Image Index Example
EXAMPLEOci Image Layout Example
EXAMPLEOci Image Manifest Example
EXAMPLEOci Runtime Config Example
EXAMPLEOci Runtime Defs Example
EXAMPLEOci Runtime Defs Vm Example
EXAMPLEOci Runtime Defs Zos Example
EXAMPLEOci Runtime Features Example
EXAMPLEOci Runtime State Example
EXAMPLEScroll within the panel for all 23 ·
Use Cases 5
What developers actually build with this provider — captured so the catalogue answers 'what is this for', not just 'what does this expose'.
What developers build with this provider.
Drop-In runc Replacement
Use youki as a drop-in replacement for runc in container engines to gain memory safety and performance benefits with no workload changes.
Rootless Container Workflows
Run containers as a non-root user for development, CI, or multi-tenant environments where elevated privileges are not desirable.
Kubernetes Workloads via containerd
Use youki under containerd to execute Kubernetes pods and workloads in production clusters.
Podman and Docker Container Execution
Configure Podman or Docker to invoke youki as the low-level OCI runtime for image execution.
Container Runtime Research and Education
Explore and prototype container runtime features in a memory-safe codebase suitable for systems research, security analysis, and teaching.
Integrations 7
Pre-built integrations with other platforms tell you where this provider already fits in a stack.
Pre-built integrations with other platforms and tools.
containerd
containerd has passed end-to-end testing against youki, enabling its use as the OCI runtime for Kubernetes and other workloads orchestrated by containerd.
Podman
Podman can be configured to use youki as its OCI runtime for both rootless and rootful container execution.
Docker
Docker can call youki as the low-level OCI runtime in place of runc for compatible workloads via daemon.json configuration.
Kubernetes
Kubernetes clusters can run youki indirectly through container runtimes such as containerd or CRI-O.
crun
youki sits alongside crun as a modern alternative to runc, focused on memory-safe systems programming in Rust.
systemd
Integrates with systemd for cgroup management and lifecycle control of container processes.
oci-spec-rs
Built on oci-spec-rs, the Rust implementation of the OCI Runtime, Image, and Distribution specifications maintained by the same organization.
Scroll within the panel for all 7 ·
Solutions 3
Packaged solutions the provider offers on top of the raw API surface.
Packaged solutions this provider offers.
Cloud Native Container Platforms
Provides a CNCF sandbox container runtime for cloud-native platforms looking to adopt a memory-safe OCI runtime under containerd or CRI-O.
Secure Multi-Tenant Hosts
Pairs rootless containers, seccomp filtering, and Rust memory safety to harden multi-tenant container hosts against runtime exploits.
Edge and Embedded Workloads
A lightweight, high-performance runtime suitable for edge and embedded deployments where resource use and predictable performance matter.
Resources
Every other property we hold for Youki — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.
Documentation 1
Reference material describing how the API behaves
Design & Contract 1
Pagination, idempotency, versioning, errors, and events
Build 2
SDKs, sample code, and the tooling you integrate with
Operate 3
Status, limits, changes, and where to get help
← All providers · Data indexed from github.com/api-evangelist/youki · machine-readable index on apis.io