Sylve

Sylve is an open-source control panel for FreeBSD virtualization and storage — and the capstone product of Alchemilla Ventures, created under the sponsorship of the FreeBSD Foundation. It brings Bhyve hypervisor management, FreeBSD Jail orchestration, and ZFS storage administration into a unified, modern web interface.

What Sylve Delivers

Sylve provides a comprehensive virtualization platform purpose-built for FreeBSD, offering:

• Bhyve Management: Create, start, stop, snapshot, and console into VMs. Configure CPU, memory, PCI passthrough, VNC, and serial access — all from the web UI. Bhyve is FreeBSD’s native hypervisor, offering near-native performance for Linux, Windows, and FreeBSD guests.

• Jails with VM-Like Workflows: FreeBSD Jails are lightweight OS-level containers that predate Docker by over a decade. Sylve treats Jails with the same lifecycle model as VMs — networking, datastores, resource limits, and console/shell access — making container orchestration on FreeBSD intuitive.

• ZFS-First Storage: Manage ZFS pools, datasets, disks, and datastores in one interface with clear VM/Jail storage mapping. ZFS provides snapshots, clones, compression, deduplication, and self-healing data integrity — all natively integrated into Sylve’s storage layer.

• Network & Service Controls: Configure physical interfaces, virtual switches, and DHCP scopes. Optional integrations include Samba for file sharing and libvirt for API-level compatibility with existing management tooling.

Architecture at a Glance

Sylve is structured into four domains:

Domain	Function
Storage	ZFS-driven with S.M.A.R.T. visibility, pool monitoring, and snapshot operations
Networking	Physical NICs paired with user-defined virtual switches published to guests
Virtualization	Bhyve VMs and FreeBSD Jails sharing the same datastore and virtual-switch primitives
Orchestration	Go backend with REST API (documented in OpenAPI/Swagger), Svelte/SvelteKit frontend

The backend is written in Go, delivering high concurrency and low memory footprint. The frontend uses Svelte/SvelteKit for a fast, reactive UI. All orchestration flows through the REST API, making it straightforward to generate clients and build integrations.

Why Sylve vs. Proxmox, TrueNAS, or Others

Attribute	Sylve	Proxmox	TrueNAS
Base OS	FreeBSD	Debian Linux	FreeBSD (Core) / Linux (Scale)
Hypervisor	Bhyve	KVM	Bhyve (Core) / KVM (Scale)
Containers	FreeBSD Jails / OCI Containers	LXC	Jails (Core) / Docker (Scale)
Storage	ZFS-native	ZFS, Ceph, NFS, LVM	ZFS-native
Clustering	Raft-based, self-contained	Corosync	TrueCommand (Scale)
Memory Footprint	~384 MB	2+ GB recommended	8+ GB recommended
License	BSD-2-Clause	AGPLv3	BSD (Core) / GPL (portions)
Deployment	Single binary (pkg install sylve)	ISO install	ISO install

Sylve’s standout characteristics:

• Extremely lightweight: Runs in ~384 MB RAM even with all major features enabled in a multi-node cluster
• Self-contained clustering: Raft-based coordination avoids heavy external clustering stacks
• Fast deployment: Single application bundle — pkg install sylve on FreeBSD >= 15
• Focused scope: Targets the application layer, leaving the underlying FreeBSD OS untouched
• UI-first workflows: VM/Jail creation, networking, DHCP, cloud-init, TPM-backed disks, and console access all from the web UI
• Permissive license: BSD-2-Clause — use, modify, and integrate without restrictive terms

Our Sylve Services

• Sylve Deployment & Configuration: We deploy Sylve on FreeBSD >= 15 bare metal servers — Dell, HPE, Supermicro, or custom hardware. Our engineers handle:

  • FreeBSD installation and hardening (CIS benchmarks, kernel tuning)
  • Sylve installation and initial configuration
  • ZFS pool design — mirror, RAID-Z1/Z2/Z3 based on your redundancy requirements
  • Network configuration — physical interfaces, virtual switches, VLANs, DHCP
  • SSL certificate setup for the web UI

• Multi-Node Sylve Clusters: Deploy Sylve’s Raft-based clustering for high availability:

  • 3+ node clusters with quorum-based failover
  • Shared storage via ZFS replication for VM/Jail migration
  • Load balancing and service distribution across nodes
  • Cluster health monitoring and automated failover validation

• Migration to Sylve: Migrate existing workloads to Sylve-managed FreeBSD:

  • From VMware/Hyper-V: Convert VMDK/VHDX to raw/qcow2 for Bhyve, import with Sylve
  • From Docker/Linux Containers: Convert Docker workloads to FreeBSD Jails with equivalent networking and storage
  • From bare metal: P2V migration using ZFS send/receive for data, then PXE-boot to FreeBSD/Sylve

• ZFS Storage Engineering: Deep ZFS expertise as part of Sylve deployments:

  • Pool design with appropriate vdev types (mirror, RAID-Z) for your workload I/O profile
  • SSD special/metadata devices and SLOG/ZIL for synchronous write acceleration
  • Snapshot schedules and retention policies
  • ZFS send/receive for replication to off-site FreeBSD/ZFS+SSH capable nodes
  • S.M.A.R.T. monitoring, scrub scheduling, and predictive failure detection

• Sylve Management & Monitoring: Ongoing management services:

  • 24/7 health monitoring — host, VM, Jail, and ZFS pool status
  • Prometheus + Grafana dashboards with Sylve and FreeBSD node exporters
  • Automated patching — FreeBSD base system, Sylve updates, and package upgrades
  • Backup integration — ZFS snapshots to remote Sylve or PBS instances
  • Capacity planning and performance optimization

Ideal Use Cases for Sylve

• Edge & Branch Infrastructure: Sylve’s ~384 MB RAM footprint makes it ideal for edge servers, branch offices, and remote sites where resources are constrained
• Development & Staging Environments: Fast-provisioned Bhyve VMs and Jails for CI/CD, test environments, and developer sandboxes — all ZFS-backed with instant cloning via snapshots
• Hosting & Colocation: Multi-tenant hosting platforms with per-customer Jails, ZFS quotas, and resource limits — BSD licensing means no per-core or per-socket licensing costs
• Security-Hardened Workloads: FreeBSD’s security track record combined with Sylve’s clean management layer provides a robust platform for security-sensitive applications
• ZFS-Native Storage Servers: Build high-integrity storage servers with Sylve’s ZFS management, Samba/NFS exports, and snapshot-based backup workflows

Why FreeBSD?

Sylve inherits FreeBSD’s strengths:

• ZFS — the gold standard for data integrity, with over 15 years of production use
• Jails — OS-level virtualization that predates and inspired Linux containers
• Bhyve — a mature, high-performance Type-2 hypervisor with broad guest OS support
• Security — Capsicum sandboxing, mandatory access control, and a stellar advisory track record
• Network Stack — pf firewall, netgraph, and advanced TCP congestion control
• Ports & Packages — 30,000+ ready-to-install applications

For organisations seeking virtualization independence with a lightweight, BSD-licensed platform, Sylve on FreeBSD is a compelling choice. Contact us to discuss your Sylve deployment or migration.