What is Varnish?
The HTTP acceleration engine at the center of your delivery stack.
The engine that keeps your origin out of the equation.
Varnish is an HTTP accelerator and reverse proxy that serves data at near-memory speed, shielding your infrastructure from traffic it should never have to handle.
When a request arrives, Varnish answers it from cache in under half a millisecond. The origin only gets involved when it has to. At scale, that distinction is the difference between infrastructure that holds and infrastructure that buckles.
For two decades, the world's most demanding web properties, streaming platforms, and enterprise pipelines have relied on Varnish to sit between their users and their backends. The same engine that handles a global broadcaster's live stream also accelerates AI data pipelines, Kubernetes ingress, and software supply chains.
One engine. Every data challenge
Varnish isn't built for one workload. The same core acceleration engine handles:
Web & API delivery
Dynamic application servers, legacy CMS platforms, and high-concurrency API traffic.
Video & media streaming
Linear live streams, VoD package servers, and high-volume asset delivery.
AI & data infrastructure
Object storage, S3-compatible data lakes, and GPU training pipelines at exabyte scale.
Software supply chains
Public and private registries including Docker Hub, npm, PyPI, and JFrog Artifactory.
Whatever the workload, the challenge is the same: serve the right bytes at speed without hammering the infrastructure behind it.
Open source or Enterprise?
Varnish Software continues to actively develop, maintain, and evolve Varnish Cache as the cloud-native, open-source distribution built for modern infrastructure.
Varnish Cache
A cloud-native foundation providing core HTTP acceleration and reverse-proxy functionality with key community features built-in.
Core Included Features
- In-process TLS termination
- Official container images & Helm chart
- Dynamic backends with TLS to origin
Varnish Enterprise
Engineered for high-concurrency workloads and massive data footprints, extending the core engine with specialized storage, security, and edge compute capabilities.
Enterprise Capabilities
Storage & Routing
- MSE 4 Storage Engine
- VHA Cache Clustering
- Intelligent Traffic Router
- Tag-Based Invalidation
Security & Compliance
- Perimeter WAF & JWT Auth
- Software Supply Chain Security
- Distributed Rate Limiting
Programmability & Ops
- 50+ Native Enterprise VMODs
- WASM Edge Compute
- Varnish Controller UI
Whether deploying community open-source instances or powering critical infrastructure with Varnish Enterprise, Varnish remains the definitive engine for serving data at memory speeds without origin strain.
How Varnish fits into your stack
Varnish Enterprise sits as a unified delivery layer between your data sources and your end consumers. The architecture adapts to your environment rather than requiring you to adapt to it.
Web app backends
Application APIs, legacy CMS platforms, and dynamic application servers.
HTTP/HTTPSVideo & media origins
Linear streams, VoD package servers, and high-volume assets.
HTTP/HTTPSObject storage / S3
Exabyte-scale cloud storage, data lakes, and AI datasets.
S3 protocolSoftware repositories
Public and private registries: Docker Hub, npm, PyPI, JFrog.
Package manager protocolsVarnish Enterprise
One extensible platform
Multi-tier architecture moving data at near-memory speeds.
Caching & acceleration
Sub-millisecond hash lookups, request coalescing, MSE 4 storage.
Clustering, HA & load balancing
Active-active replication, origin shielding, L7 backend directors.
Perimeter security
In-process TLS, JWT authentication, edge WAF, supply chain filters.
Programmable edge compute
Atomic VCL routing, per-request header control, WebAssembly execution.
Observability & telemetry
Real-time streaming, JSON logs, OpenTelemetry traces, Prometheus metrics.
Global portals & APIs
Web users, banking API clients, and retail consumers.
OTT streaming devices
Smart TV platforms, connected devices, and live media audiences.
AI & compute clusters
GPU training arrays, HPC simulation nodes, and analytical systems.
S3 + POSIX
What makes it fast
Three things determine whether infrastructure holds under pressure or buckles under it.
Speed
When a request arrives, Varnish answers from memory. Sub-0.5ms cache hits mean the origin never sees traffic it shouldn't have to handle. At scale, that's the difference between infrastructure that performs and infrastructure that strains.
Resilience
Cache state survives restarts and software updates intact. There's no cold-start origin storm after maintenance, no rebuild period after a node change. Clustered deployments absorb failures without traffic disruption.
Control
Every routing decision, header manipulation, and access rule is expressed in code, compiled to native execution, and swappable at runtime without dropping a single active connection. The platform does exactly what you tell it to, at the speed you need it to.
Built for workloads that can't afford to fail
Varnish Enterprise powers a purpose-built product family for the highest-demand use cases:
Trusted infrastructure, openly built
Open-source heritage
Varnish has its roots in open source, and that heritage shapes how the commercial product is built and maintained. Verified binaries, signed packages, visible release pipelines, and predictable upgrade paths are not afterthoughts, they are how the engineering team operates.
Support & stability
Commercial deployments come with SLA-backed vendor support, validated software streams, and upgrade pathways that don't require a rearchitect. Storage failures isolate without restart penalties. Clustered deployments absorb node changes without traffic disruption.
Battle tested
When infrastructure teams ask whether they can depend on Varnish for critical production workloads, twenty years of deployments at global scale is the answer.
Engineering principles
Architectural choices for absolute performance
Infrastructure depends on more than a standard proxy layer. These are the engineering decisions that make Varnish behave differently under load.
CORE ARCHITECTUREVarnish is built around storage performance. Every request follows a rapid hash lookup straight into system memory, shielding origin infrastructure from traffic it should never see. Concurrent requests for the same object are coalesced into a single upstream fetch. Cache-to-cache clustering means a peer absorbs the fetch if a node misses, so the backend never takes unnecessary load.
STORAGE ENGINEMSE 4 manages terabyte-class caching without exhausting system resources.
Hybrid memory + disk architecture
Pins high-demand hot objects inside RAM while cold data automatically falls back to low-cost disk arrays under a self-regulating Memory Governor.
The Varnish Configuration Language (VCL) is a domain-specific execution engine designed to manage per-request behavior programmatically.
VCL compiles to native code via C and swaps atomically at runtime without dropping a single active connection.
TLS termination runs directly inside the multi-threaded cache runtime rather than through an external proxy hop.
Eliminates internal proxy-hop latency to hit benchmarks clear of 150+ Gbps.
MSE 4 metadata indexing maps and storage structures survive hardware restarts and software updates completely intact.
Provides immediate hot-state recovery, eliminating cold-cache origin storms.
MODULARITYSupports over 50 built-in Varnish Modules (VMODs) alongside high-performance edge compute add-ons like WebAssembly functions to inject complex request logic and enterprise security controls right at the perimeter.
Core capabilities
Engineered for enterprise scale
An extended capability breakdown for teams conducting a detailed evaluation
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Storage architecture and delivery performance
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Edge security engineering and secure transport
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High availability, invalidation, and edge compute
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Enterprise observability and integrations
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Open source tooling for compute and cloud-nativity
Gateway API
A full Kubernetes Gateway API implementation backed by the world's fastest HTTP accelerator. Delivers standards-compliant ingress routing with Varnish's legendary performance.
tinyKVM
Designed for high-performance computing and CDN edge servers, tinyKVM allows standard Linux binaries to run securely in micro-VMs with near-native execution speeds.
Get started
Where to go next
Running serious traffic?
Talk to the team about Varnish Enterprise.
Deploying on Kubernetes?
Install the Gateway API implementation directly into your cluster.
Building a CDN or streaming platform?
Explore Ora Streaming and Varnish CDN.
Try Open Source
Spin up Varnish Cache using official project container configurations.