FAQ

FAQ

Questions people evaluating Kryton actually ask, before they've decided to adopt it. Already decided? docs/USER-GUIDE.md is a better starting point.

Licensing & cost

Is it really free? Yes. Apache-2.0 — use, modify, and run it for personal, lab, and commercial production use at no charge, subject to preserving notices (see NOTICE). No Windows media or license keys are shipped — that stays the operator's responsibility. See the README's License section.

What does "Enterprise" mean here? Production support, SLAs, and Zyvor's other commercial products are licensed separately. Contact sales@zyvor.dev. Nothing in this repository requires it.

Support

What if I find a bug? Open a GitHub issue.

What if I find a security vulnerability? See SECURITY.md — private reporting via GitHub Security Advisories. Note its own text: "Kryton does not yet maintain long-term-support branches. Security fixes land on main and the latest tagged release; older tags are not backported."

Production readiness

Is this production-ready? It depends which provider. Per docs/GA.md: the KubeVirt provider is the GA path. The dockur lab provider "remains a lab installer, not GA." Also explicitly out of GA scope today: running more than one krytond replica — docs/ARCHITECTURE.md documents a single-writer TTL reconciler and in-process event/SSE bus, so multi-replica isn't safe yet. Read docs/GA.md's full checklist before a production go-live decision.

What Kryton explicitly doesn't do: it's not a Windows installer, activation service, or media distributor, and not a raw KubeVirt YAML factory for callers — see the README's "What Kryton is not" section.

Architecture

How does the provider abstraction work? One Go provider.Provider interface; callers only ever see REST+CloudEvents, never backend-specific detail. Four providers translate the same contract: demo (in-memory), dockur (real Windows via dockur/windows on Docker/Podman+KVM, lab-grade), libvirt (Linux cloud images on a KVM host, initial backend), and kubevirt (production Windows and Linux VMs on Kubernetes). See docs/ARCHITECTURE.md.

Does Kryton run Linux? Yes. Linux guests use the same machine API as Windows ones, on the libvirt provider (a single KVM host) or on kubevirt (cloud-init). Guests are configured with a username and SSH public keys and are password-locked. See docs/LINUX-TEMPLATES.md.

Which Linux images? Eleven amd64 cloud images: Ubuntu 22.04, 24.04 and 26.04, Debian 12 and 13, Rocky Linux 9 and 10, AlmaLinux 9 and 10, CentOS Stream 10, and Fedora 44. Kryton ships no images; kryton-image fetch downloads them from the distribution and only accepts them against an operator-approved SHA-256.

Does it integrate with other Zyvor products? Yes — see docs/ATLAS.md for the Zyvor Atlas storage control plane integration.

Hardware & platform

What do I need to run it? Go 1.27.1+; for the dockur provider, Docker/Podman with KVM; for the libvirt provider, KVM with libvirt, qemu-img and genisoimage; for the kubevirt provider, a Kubernetes cluster with KubeVirt and CDI installed (see docs/DEPLOYMENT.md and docs/STORAGE.md for storage-class requirements).

Windows licensing? Not Kryton's concern by design — "Microsoft media, activation, and entitlement remain the operator's responsibility" (README).