Independent and Affordable Cloud Infrastructure
In the age of AI and rising virtualization licensing costs, we believe that old hardware should not be thrown away or cycled out. Instead, it should be racked and turned into a hypervisor for compute workloads. To learn more about this vision, read our origin story.
Guestlet
Guestlet is a virtualization platform built on open source foundations: PostgreSQL, Debian, and QEMU/KVM. It has an easy-to-use web interface, API, and Terraform provider.
To see a complete list of Guestlet functionality, checkout the project page.
All-in-one compute and virtualization platform
From Dell PowerEdges to Raspberry Pis, Guestlet supports x86_64 and ARM CPUs. We built a custom driver to interface with QEMU so that virtual machine management is controlled and predictable. This predictability allows for seemlessly hot-plugging devices such as network cards, block devices, and live migration.
Namespaced and isolated networking
Virtual machines are deployed into a VPC Network. This is an isolated network namespace that supports NAT Gateways, Public IPs (Elastic IPs), Physical IPs (local physical network IPs), and firewalls (Security Groups). Networking is seemless between different architectures and does not require configuration.
Secure by design
From the beginning, Guestlet was designed to ensure that virtual machines and the networks they reside in are sandboxed. To achieve this, all virtual machines run with the latest security mitigations, in a SECCOMP sandbox, least privilege, and network namespace. Because virtual machines are running in a sandboxed VPC Network, all network traffic can be logged with packet captures. The VPC Network also caches and logs DNS queries. Lastly, all communication in the control plane is encrypted with mTLS.
Built for automation
Automation is a critical component for running and managing cloud infrastructure. Guestlet is a 100% API driven control plane. All communication in the control plane is with JSON + REST, no exceptions. This approach allows us to offer essential automation functionality such as a Terraform provider, API access keys, and RBAC. Provisioning of virtual machines is also automatable with cloud-init.
Platform Observability, Dashboards, and Metrics
What is a virtualization platform without dashboards, metrics, and observability? Guestlet ensures complete insight into the platform by collecting metrics on virtual machines, hypervisors, the network, and more. For maximum flexibility, the Prometheus remote_write 1.0 specification is used; this allows for metrics to be stored in any system that supports it.
Easy to deploy
One of the primary goals with Guestlet is to make it easy to deploy. To make this a reality, it was designed to have no C dependencies and a static binary. This reduces the attack surface and makes it easier to deploy. Our target platform is Linux KVM, specifically Debian 13, but any distribution that supports KVM will work (see docs for details).
Actively maintained documentation
We believe that it's important to understand the platform that you're using or potentially evaluating. To help you achieve this, we have clear documentation on the architecture and installation process. We also maintain and regularly update our documentation. If something is not clear, please let us know so that we can fix it.
Recent blog posts
How to use authorization to secure REST APIs
October 23, 2026 by J. Wubben
Phantom is a go-fiber v3 middleware that uses authorization callbacks to secure REST APIs. Rate limiting, fuzzing, IP ACLs, and Token Bucket are explored.
Distro hopping is still one of the best online hobbies
August 24, 2026 by J. Wubben
Distro hopping is still one of the easiest ways to farm XP, level up your technical skills, grow a badass beard, and take back control over your operating system.
Mountlet: How to Fabricate and Assemble a 6U Server Rack
August 17, 2026 by J. Wubben
Using the designs from the previous blog post, a 6U Server Rack is fabricated and assembled.
Mountlet: How To Design a Server Rack that Supports Cage Nuts
Updated October 7, 2026 by J. Wubben
Using the original 24U server rack post, new 6U, 8U, 12U, and 24U server rack posts are created that support cage nuts.
Questions
Currently, Guestlet is in private beta and access is granted on a case-by-case basis. Testers and users will be needed soon, so if you are interested, please contact us explaining your use case, amount of systems, desired outcome, etc.
We regularly post updates to our blog. You can also follow us on Mastodon, and Bluesky.
A newsletter will be launching soon, if you want to get on that list in the mean time feel free to contact me letting me know. When I have it ready, I'll automatically put you on the list.
Guestlet is being developed by Minnesota-based indie developer, Invirtuate! All of our art and illustrations are made by Fanciful Realities.
Yes, demos are scheduled by appointment. Feel free to contact us if interested.
