High-performance block storage caching for modern data centers
We build, maintain, and commercially support OpenCAS — the open-source framework for accelerating block storage with intelligent caching. From kernel-level engineering to enterprise integration.
The team behind OpenCAS
Unvertical is a Poland-based company founded by the core maintainers of the Open Cache Acceleration Software (OpenCAS) project. We've been building CAS technology since 2016 — first inside Intel, then as the lead open-source maintainers and commercial partners for organizations worldwide after Intel CAS reached end-of-life in 2023.
Our expertise sits at the intersection of Linux kernel development, storage systems architecture, and NVM technology. We know this codebase intimately because we wrote it, and we understand the workloads it serves because we've deployed it across production environments worldwide.
We operate on an open-core model: the foundational caching engine remains fully open source under the BSD-3 license, while we offer enterprise tooling, professional services, and custom development to organizations that need production-grade support and integration.
Kernel-Level Expertise
Deep experience with Linux kernel storage subsystem, out-of-tree module development, and performance optimization at the block layer.
Open Source First
Core caching engine (OCF) and Linux adapters are and will remain open source. We build trust through transparency.
Global Reach, European Roots
Based in Poland, serving data center operators and enterprise teams across Europe, North America, and Asia-Pacific.
Unvertical OpenCAS
Open Cache Acceleration Software — a mature, battle-tested block-level caching framework that accelerates backend storage using higher-performance local media.
Accelerate your storage, transparently
OpenCAS sits between your applications and backend storage devices, caching frequently accessed data on faster local media (NVMe SSDs, Intel Optane, or any high-performance block device). It operates at the block level as a Linux kernel module, which means it's transparent to applications — no code changes, no API integrations, no filesystem dependencies.
At the core is the Open CAS Framework (OCF), a high-performance caching meta-library written in C. OCF is modular and embeddable: it powers both the Linux kernel adapter (Open CAS Linux) and an SPDK block device adapter for user-space storage applications.
OpenCAS supports multiple cache modes (write-through, write-back, write-around, pass-through), flexible I/O classification by block size, file path, directory, or metadata type, and ships with a comprehensive test framework for validation and CI/CD integration.
The entire project is licensed under BSD-3 — no vendor lock-in, no usage restrictions, no surprises.
Key Capabilities
- Block-level caching — transparent to all applications and filesystems
- Multiple cache modes: write-through, write-back, write-around, pass-through
- Flexible I/O classification by block size, file, directory, or metadata
- Linux kernel module with active maintenance for current kernel versions
- SPDK adapter for user-space storage applications
- Modular OCF core — embeddable in custom storage stacks
- Comprehensive test framework and CI/CD tooling
- BSD-3 license — fully open, no restrictions
Where OpenCAS makes the difference
OpenCAS serves environments where the latency or throughput of accessing backend storage directly limits business outcomes.
Virtualization Platforms
KVM/QEMU, Proxmox, OpenStack — accelerate virtual disk I/O with transparent block-level caching. No guest OS modifications required.
Database Acceleration
Reduce query latency for databases running on SAN or shared storage. Effective for mixed OLTP/OLAP workloads where hot dataset fits in cache.
HCI & Software-Defined Storage
Storage vendors can embed OCF directly into their products. OEM licensing available for ISVs building HCI or SDS solutions.
SAN & Direct-Attached Acceleration
Cache frequently accessed blocks from slower SAN or DAS backends on local NVMe. Transparent to applications, no storage rebuild needed.
From evaluation to production
Whether you need help evaluating OpenCAS, integrating it into a custom kernel, or tuning it for your workload — we're the team that wrote it.
Consulting
Architecture review and workload analysis for your storage stack. We assess whether caching is the right approach, recommend configuration strategies, and design integration plans for your infrastructure.
Configuration Validation
OpenCAS runs as an out-of-tree kernel module. We build, test, and certify releases for your specific kernel version, OS distribution, and hardware — including custom or modified kernels.
Custom Development
Need a new integration layer for your storage platform? A custom caching policy? We develop features in the core engine and build dedicated plugins for your environment.
Premium Support
SLA-backed technical support with guaranteed response times. Direct access to the engineers who maintain the codebase. Priority issue resolution and root cause analysis.
Training
Hands-on programs for your infrastructure team. Covers OpenCAS architecture, deployment best practices, performance tuning, troubleshooting, and operational runbooks. On-site or remote.
Benchmarking & PoC
We run OpenCAS on your actual workloads, produce detailed performance reports, and help you make informed decisions with real data — not vendor marketing numbers.
Subscription plans and service levels
The caching engine stays free and open source. Every plan is delivered by the engineers who have built and maintained CAS since 2016, so the packages, tooling, and support you pay for come from the experts.
Starter
- Complete OpenCAS caching functionality (open source)
- Linux kernel modules and CLI management tools (open source)
- SPDK integration (open source)
- Self-service / community support
- Access to packages for major Linux distributions
- OpenCAS documentation and getting-started guides
Basic
Everything in Starter, plus:
- Access to the package repository with official, tested installation packages
- Automatic metadata migration between OpenCAS versions
- Advanced telemetry and monitoring dashboards
- SLA-backed support provided directly by maintainers
- 5 support tickets per year
- Initial support response time: 2 business days (9-5 CET/CEST)
Premium
Everything in Basic, plus:
- Solution engineering, deployment support and performance tuning
- Access to Long-Term Support OpenCAS versions
- Custom kernel support
- Integration layers for enterprise storage platforms
- Custom features / integrations development and support
- Unlimited support tickets
- Initial support response time: 1 business day (9-5 CET/CEST)
- IM and phone support within business hours (9-5 CET/CEST) for high severity tickets
Pricing is per node and depends on the plan and the size of your deployment — request a quote and we'll tailor it to you.
The maintainers are the vendor
You're not buying from a company that packages someone else's open-source project. You're working directly with the people who architect, maintain, and evolve the technology.
Years on CAS
Building caching technology since 2016 — from Intel CAS to OpenCAS and now NVMC.
Layers of Indirection
Your support tickets are handled by the people who write the code. No outsourced L1 chains.
No Lock-In
The core is open source. You can fork, audit, or self-support. We earn your business on quality.
Products, One Stack
OpenCAS and NVMC share the OCF foundation. Expertise in one deepens the other.
Got a storage question? Just ask.
No sales pitch, no chatbot, no scripted support rep. Your message lands with the engineers who wrote the code. Tell us what you're running and we'll take it from there.