[Sandbox] Unbounded

### Project summary

Unbounded extends any conformant Kubernetes control plane with worker nodes across clouds, on-premises infrastructure, bare metal, and edge locations through integrated provisioning and cross-site networking.

### Project description

Unbounded helps organizations use computing capacity spread across public clouds, private data centers, bare-metal infrastructure, and edge locations as part of one Kubernetes cluster.

Today, teams often cannot run workloads because their primary cloud region has reached a quota limitation, a required machine type is unavailable, or GPUs are scarce. They may also own useful hardware in other locations that is difficult to connect to an existing cluster. The usual response is to create and operate additional clusters, introducing more deployment, networking, security, and maintenance work.

Unbounded addresses this pain point by connecting suitable machines from different environments, joining them to the existing Kubernetes cluster as worker nodes, and establishing the networking needed for workloads to communicate across locations. Developers can continue using familiar Kubernetes applications and workflows rather than adopting a separate workload model.

By bringing machine management and cross-location networking together, Unbounded helps platform teams make better use of available infrastructure, reach specialized or geographically distributed computing resources, and reduce the operational burden of managing separate clusters solely because capacity exists in different places.

### Project vs Reference Architecture/Implementation

- [x] This is a reusable open source project designed for broad adoption, not a reference architecture, reference implementation, or demonstration of patterns

### Org repo URL (provide if all repos under the org are in scope of the application)

_No response_

### Project repo URL in scope of application

https://github.com/Azure/unbounded

### Additional repos in scope of the application

_No response_

### Website URL

https://unbounded-cloud.io/

### Roadmap

https://github.com/Azure/unbounded/blob/main/ROADMAP.md

### Roadmap context

Unbounded's roadmap is focused on enabling users to treat compute across clouds, specialized GPU providers, on-premises environments, and edge sites as one accessible Kubernetes resource pool. Near-term work improves reliable provisioning and networking across those locations, while subsequent work in the roadmap adds GPU-aware capacity selection, simpler upgrades and recovery, stronger security and scalability. Together, these priorities aim to reduce the operational cost of fragmented infrastructure while giving users more choice over where workloads run.

### Contributing guide

https://github.com/Azure/unbounded/blob/main/CONTRIBUTING.md

### Code of Conduct (CoC)

https://github.com/Azure/unbounded/blob/main/CODE_OF_CONDUCT.md

### Adopters

_No response_

### Maintainers file

https://github.com/Azure/unbounded/blob/main/MAINTAINERS.md

### Security policy file

https://github.com/Azure/unbounded/blob/main/SECURITY.md

### Standard or specification?

N/A

### Business product or service to project separation

Unbounded is an open-source, Apache 2.0 licensed project currently sponsored by Microsoft and hosted in the Azure GitHub organization. It is designed for any conformant Kubernetes distribution and for infrastructure across cloud, specialized compute, on-premises, and bare-metal, giving users freedom to choose and combine environments without dependence on a Microsoft product. The upstream project has its own public governance, roadmap and release process, while Microsoft and other cloud providers may build separate downstream integrations with their own branding and service commitments. Ultimately, no vendor's product or infrastructure determines Unbounded project's architecture or access to its features.

### Why CNCF?

Unbounded spans Kubernetes node lifecycle, networking, runtimes, observability, and accelerator infrastructure. CNCF offers the neutral governance and cross-project forum needed to develop those interfaces of Unbounded without favoring a single cloud provider or hardware vendor. Membership in the CNCF will enable Unbounded users and operators to have a stronger voice in priorities, providers an equal basis for integrations, and contributors a well-supported path for deeper involvement in the project ecosystem.
In turn, Unbounded in its early stage will contribute a practical testbed for treating fragmented compute as Kubernetes capacity and for defining interoperability with adjacent CNCF projects.

### Benefit to the landscape

Unbounded addresses a gap between provisioning nodes within a single infrastructure domain and orchestrating workloads across multiple clusters. Its differentiator is the combination of heterogeneous remote-node lifecycle and intra-cluster networking - multiple enrollment path and network fabric are managed together, while workloads continue to use standard Kubernetes APIs.
Unbounded enables operators to maintain their known model for distributed capacity, provides developers access to locality-sensitive compute without a new workload API, and standardizes on a declarative machine and network lifecycles that platform teams maintain. It also gives the Kubernetes ecosystem a way to test a single cluster's limitations around failure domains and control-plane reachability to inform users on their choice to either extend their cluster or federate several clusters.

### Cloud native 'fit'

Unbounded makes capacity outside a cluster's primary infrastructure available as native Kubernetes nodes, and accessible to users via standard Kubernetes APIs. The project uses declarative Kubernetes resources and controllers while preserving standard pods, scheduling, and operational tooling across conformant distributions.
Its primary cloud native fit is **Provisioning / Automation and Configuration**, with a secondary fit in **Runtime / Cloud Native Network**, and a strong alignment with **TAG infrastructure**.

### Cloud native 'integration'

Unbounded integrates with the following CNCF projects:

- Kubernetes: Unbounded depends on Kubernetes APIs, custom resource definitions (CRDs), kubelet and kubeadm bootstrap, and controller runtime for its control and node model.
- containerd: Unbounded depends on containerd as the worker node runtime and integrates with its APIs for image distribution.
- Prometheus: This project complements Prometheus by exposing component and networking metrics in Prometheus format.
- ORAS: This project uses ORAS libraries to consume and publish OCI artifacts used by release and image-distribution workflows.
- Cilium: Unbounded complements Cilium by adding cross-location connectivity while allowing clusters to retain Cilium as their existing container networking interface (CNI).

### Cloud native overlap

OpenYurt (https://openyurt.io/): This project and Unbounded both extend a Kubernetes cluster to remote notes while preserving Kubernetes API access. OpenYurt emphasizes edge autonomy and disconnected operation, while Unbounded focuses on heterogeneous capacity through multiple enrollment paths with integrated cross-location networking.
KubeEdge (https://kubeedge.io/): Both projects connect remote or edge compute to a Kubernetes control plane. KubeEdge focuses on cloud-edge synchronization and device management and Unbounded highlights bringing together external machines, sometimes from various locations, and connecting them as worker nodes.

### Similar projects

The closest projects in similarity are [OpenYurt](https://openyurt.io/) and [KubeEdge](https://kubeedge.io/).

### Landscape

No, this project is not yet listed in the Cloud Native Landscape.

### Insights

No, this project is not yet listed on LFX Insights.

### Trademark and accounts

- [x] If the project is accepted, I agree to donate all project trademarks and accounts to the CNCF

### IP policy

- [x] If the project is accepted, I agree the project will follow the CNCF IP Policy

### Will the project require a license exception?

N/A - Unbounded uses the Apache 2.0 license.

### Does the project utilize any dependencies with licenses not on the allowlist or an approved exception?

N/A - All licenses are on the allowlist.

### Project "Domain Technical Review"

The Unbounded project team plans to attend and present at the next TAG Infrastructure meeting on 9/25/2026, and completed General Technical Review questionnaire will be completed and attached here shortly.

### Application contact email(s)

sachidesai@microsoft.com, jawilder@microsoft.com

### Contributing or sponsoring entity signatory information

If an organization:
| Name | Address | Type (e.g., Delaware corporation) | Signatory name and title | Email address |
|-----------|-----------|-----------|-----------|-----------|
| Microsoft Corporation | 1 Microsoft Way, Redmond, Washington, 98052 | US Corporation | Brendan Burns
Technical Fellow and Corporate Vice President | bburns@microsoft.com |

Or, if an individual or individual(s):
| Name | Country | Email address |
|-----------|-----------|-----------|
| | | |
| | | |
| | | |

### CNCF contacts

Bridget Kromhout (Microsoft) can help answer questions about the Unbounded project.

### Additional information

_No response_