# Migrate from Fastly to Azion | Full Guide
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A platform migration usually begins long before the first service is cloned or the first domain is cut over. It starts when a team notices that delivery, compute, cache, security, and observability workflows are spread across too many configuration surfaces.
For teams using Fastly, this moment often appears after years of accumulated delivery logic: services with multiple origins, VCL snippets, Compute packages, dictionaries, cache overrides, TLS automation, WAF policies, logging endpoints, and inspector dashboards. Each layer may work independently, but the combined operational model can slow releases and make changes harder to validate.
For teams currently using Fastly Full-Site Delivery, Compute, Edge Data Storage, Object Storage, Image Optimizer, Fastly Next-Gen WAF, DDoS Protection, Bot Management, Platform TLS, High Volume Logging, Domain Inspector, Origin Inspector, or Log Explorer & Insights, Azion provides equivalent capabilities through Applications, Functions, KV Store, Object Storage, Image Processor, Firewall, Web Application Firewall, DDoS Protection, Bot Manager, Certificate Manager, Data Stream, Real-Time Events, and Real-Time Metrics.
The strongest reason to migrate is not simply to replace one vendor with another. It is to consolidate application delivery, compute, storage, security, and observability into a unified platform designed for globally distributed applications.
## How Fastly to Azion Migration Works
Traditional platform migrations often require rewriting service logic, reconfiguring origins from scratch, and recreating security and logging behavior under pressure. This approach creates operational risk, extends timelines, and makes rollback harder.
The Azion migration approach preserves your application behavior while transitioning to a unified platform:
1. **Incremental migration path.** Start with one representative Fastly service, validate delivery and security behavior on Azion, and expand to additional services only after the pattern is proven.
2. **Preserved application logic.** Origins, cache policies, redirects, headers, security controls, and data access patterns map to Azion Applications, Rules Engine, Functions, Connectors, KV Store, and Object Storage with focused configuration changes.
3. **Unified platform model.** Instead of managing delivery, compute, storage, security, and observability as disconnected products, Azion brings these capabilities together with consistent APIs, Console workflows, and deployment patterns.
## Feature Mapping
The following table provides a comprehensive mapping of Fastly products and configuration areas to their Azion equivalents. A dash (`-`) indicates that Azion does not currently offer a direct equivalent.
| Fastly Product or Feature | Description | Azion Equivalent |
| :------------------------ | :---------- | :--------------- |
| **Full-Site Delivery** | Website, application, API, and mobile delivery through Fastly services. | [Applications](https://www.azion.com/en/documentation/products/build/applications/) |
| **Fastly services** | Main delivery resource for domains, origins, caching, request handling, and service versions. | [Applications](https://www.azion.com/en/documentation/products/build/applications/) + [Workloads](https://www.azion.com/en/documentation/products/secure/workloads/) |
| **Domains** | Hostnames associated with Fastly services. | [Workloads](https://www.azion.com/en/documentation/products/secure/workloads/) |
| **Hosts and origins** | Backend origin configuration for Fastly delivery services. | [Connectors](https://www.azion.com/en/documentation/products/secure/connectors/) |
| **Origin Shield / shielding patterns** | Reduce origin traffic by routing cache misses through an intermediate shield location. | [Origin Shield](https://www.azion.com/en/documentation/products/secure/connectors/origin-shield/) + [Tiered Cache](https://www.azion.com/en/documentation/products/build/applications/cache/tiered-cache/) |
| **Conditions** | Request, cache, and response conditions in Fastly service configuration. | [Rules Engine for Applications](https://www.azion.com/en/documentation/products/build/applications/rules-engine/) |
| **Request settings** | Request manipulation, forwarding, and handling behavior. | [Rules Engine for Applications](https://www.azion.com/en/documentation/products/build/applications/rules-engine/) + [Functions](https://www.azion.com/en/documentation/products/build/applications/functions/) |
| **Response settings** | Response header and delivery behavior. | [Rules Engine for Applications](https://www.azion.com/en/documentation/products/build/applications/rules-engine/) |
| **VCL snippets / custom VCL** | Custom delivery logic for redirects, headers, cache keys, origin selection, and request control. | [Rules Engine for Applications](https://www.azion.com/en/documentation/products/build/applications/rules-engine/) + [Functions](https://www.azion.com/en/documentation/products/build/applications/functions/) |
| **Compute** | Serverless compute platform that runs custom code on Fastly's network. | [Functions for Applications](https://www.azion.com/en/documentation/products/build/applications/functions/) |
| **Compute packages** | Packaged application code deployed to Fastly Compute. | [Functions](https://www.azion.com/en/documentation/products/build/applications/functions/) + [Azion CLI](https://www.azion.com/en/documentation/products/azion-cli/overview/) |
| **Edge Data Storage** | Key-value data used by Fastly Compute services. | [KV Store](https://www.azion.com/en/documentation/products/store/kv-store/) |
| **Object Storage** | S3-compatible object storage integrated with delivery and compute services. | [Object Storage](https://www.azion.com/en/documentation/products/store/object-storage/) |
| **Cache Reservation** | Reserved cache capacity for content on Fastly. | [Cache](https://www.azion.com/en/documentation/products/build/applications/cache/) + [Tiered Cache](https://www.azion.com/en/documentation/products/build/applications/cache/tiered-cache/) |
| **Cache APIs** | Programmatic cache interaction patterns for Compute applications. | [Functions](https://www.azion.com/en/documentation/products/build/applications/functions/) + [Cache](https://www.azion.com/en/documentation/products/build/applications/cache/) + [Real-Time Purge](https://www.azion.com/en/documentation/products/build/applications/real-time-purge/) |
| **Streaming Delivery** | Delivery of live and video-on-demand streaming content. | [Applications](https://www.azion.com/en/documentation/products/build/applications/) + [Cache](https://www.azion.com/en/documentation/products/build/applications/cache/) + [Object Storage](https://www.azion.com/en/documentation/products/store/object-storage/) |
| **Media Shield for Live** | Reduces origin traffic for live video workflows. | [Tiered Cache](https://www.azion.com/en/documentation/products/build/applications/cache/tiered-cache/) + [Origin Shield](https://www.azion.com/en/documentation/products/secure/connectors/origin-shield/) |
| **Media Shield for VOD** | Reduces origin traffic for video-on-demand workflows. | [Tiered Cache](https://www.azion.com/en/documentation/products/build/applications/cache/tiered-cache/) + [Origin Shield](https://www.azion.com/en/documentation/products/secure/connectors/origin-shield/) |
| **Image Optimizer** | Real-time image transformation and optimization service. | [Image Processor](https://www.azion.com/en/documentation/products/build/applications/image-processor/) |
| **WebSockets** | Long-lived, bidirectional communication for real-time applications. | [WebSocket Proxy](https://www.azion.com/en/documentation/products/build/applications/websocket/) + [WebSocket API](https://www.azion.com/en/documentation/runtime/api-reference/websocket/) |
| **Fanout** | Publish-subscribe messaging patterns on Fastly. | [Functions](https://www.azion.com/en/documentation/products/build/applications/functions/) + [WebSocket Proxy](https://www.azion.com/en/documentation/products/build/applications/websocket/) |
| **AI Accelerator** | Semantic caching and traffic acceleration for generative AI APIs. | [AI Inference](https://www.azion.com/en/documentation/products/ai/ai-inference/) + [Cache](https://www.azion.com/en/documentation/products/build/applications/cache/) |
| **Fastly Next-Gen WAF** | Web application firewall for suspicious traffic detection and application protection. | [Web Application Firewall](https://www.azion.com/en/documentation/products/secure/firewall/web-application-firewall/) |
| **Edge Rate Limiting** | Count requests and apply actions when limits are exceeded. | [Rules Engine for Firewall](https://www.azion.com/en/documentation/products/secure/firewall/rules-engine/) + [Functions for Firewall](https://www.azion.com/en/documentation/products/secure/firewall/functions/) |
| **Fastly DDoS Protection** | DDoS visibility and mitigation. | [DDoS Protection](https://www.azion.com/en/documentation/products/secure/firewall/ddos-protection/) + [Network Shield](https://www.azion.com/en/documentation/products/secure/firewall/network-shield/) |
| **Bot Management** | Detect and respond to automated traffic. | [Bot Manager](https://www.azion.com/en/documentation/products/secure/firewall/bot-manager/) + [Bot Manager Lite](https://www.azion.com/en/documentation/products/secure/firewall/bot-manager-lite/) |
| **Certainly** | Fastly certificate authority for TLS certificates. | [Certificate Manager](https://www.azion.com/en/documentation/products/secure/firewall/certificate-manager/) |
| **Platform TLS** | API-driven TLS certificate and key management. | [Certificate Manager](https://www.azion.com/en/documentation/products/secure/firewall/certificate-manager/) + [Azion API](https://www.azion.com/en/documentation/products/overview-azion-api/) |
| **TLS Service Options** | TLS configuration for serving sites and applications over HTTPS. | [Certificate Manager](https://www.azion.com/en/documentation/products/secure/firewall/certificate-manager/) + [Workloads](https://www.azion.com/en/documentation/products/secure/workloads/) |
| **High Volume Logging** | Real-time log streaming to external destinations. | [Data Stream](https://www.azion.com/en/documentation/products/observe/data-stream/) |
| **Log Explorer & Insights** | Inspect and monitor log data on the Fastly platform. | [Real-Time Events](https://www.azion.com/en/documentation/products/observe/real-time-events/) |
| **Domain Inspector** | Domain-level traffic visibility and reporting. | [Real-Time Metrics](https://www.azion.com/en/documentation/products/observe/real-time-metrics/) |
| **Origin Inspector** | Origin response visibility and reporting. | [Real-Time Metrics](https://www.azion.com/en/documentation/products/observe/real-time-metrics/) + [Real-Time Events](https://www.azion.com/en/documentation/products/observe/real-time-events/) |
| **Observability features** | Traffic, security, performance, and origin visibility. | [Real-Time Metrics](https://www.azion.com/en/documentation/products/observe/real-time-metrics/) + [Real-Time Events](https://www.azion.com/en/documentation/products/observe/real-time-events/) + [Data Stream](https://www.azion.com/en/documentation/products/observe/data-stream/) |
| **Fastly API** | Programmatic management of Fastly resources. | [Azion API](https://www.azion.com/en/documentation/products/overview-azion-api/) |
| **Fastly CLI** | Command-line workflow for Fastly services and Compute projects. | [Azion CLI](https://www.azion.com/en/documentation/products/azion-cli/overview/) |
| **Fastly Terraform Provider** | Infrastructure as Code for Fastly resources. | [Terraform Provider](https://www.azion.com/en/documentation/products/terraform-provider/) |
## Migration Strategy
The migration is organized around Azion's four product categories, allowing teams to plan and execute each layer independently:
- **Build**: migrate delivery services, origins, VCL behavior, Compute code, cache policies, image optimization, streaming, WebSocket, and AI acceleration patterns.
- **Secure**: migrate domains, certificates, WAF policies, DDoS protection, bot controls, and rate limiting.
- **Store**: migrate object storage and edge key-value data to Object Storage and KV Store.
- **Observe**: migrate logging, inspectors, metrics, dashboards, and external log destinations to Azion's real-time observability stack.
:::note
If you do not need near-zero downtime, you can migrate in phases with maintenance windows. This allows stopping writes during each migration step without requiring parallel data synchronization.
:::
## Build
The Build category covers application deployment, delivery configuration, compute, routing, cache, and media optimization. Start here to recreate the application behavior users see before moving security, data, and observability layers.
### 1. Project Setup on Azion
The first step brings your application into Azion in a way that is familiar to teams that already manage Fastly services and Compute projects. If you have used Fastly service versions, Compute packages, and CLI deployments, you already understand the pattern: define configuration, deploy a version, validate behavior, and promote traffic when ready.
Azion follows a similar workflow but consolidates application delivery, Functions, rules, security, and observability in the same platform context.
#### Key Differences
| Aspect | Fastly | Azion |
| :----- | :----- | :---- |
| **Primary delivery resource** | Service | Application + Workload |
| **Config file** | `fastly.toml`, VCL, service version config | `azion.config.js` and Console configuration |
| **Compute deployment** | Compute package | Function + Function Instance |
| **Routing and behavior** | VCL, conditions, request/response settings | Rules Engine + Functions |
| **Observability** | Inspectors, logging endpoints, Log Explorer | Real-Time Metrics, Real-Time Events, Data Stream |
#### Connect Your Repository
1. Open [Azion Console](https://console.azion.com/).
2. Click **+ Create** > **Import from GitHub**.
3. Authorize the Azion GitHub App.
4. Select the repository you want to migrate.
:::note
Keep the first deployment intentionally small. Do not try to migrate every Fastly service, domain, VCL snippet, Compute package, storage dependency, security policy, and logging endpoint at once. Start by proving one representative service can run on Azion.
:::
#### Configure Your Build
Azion auto-detects your framework and configures build settings. Override the detected preset in `azion.config.js`:
{
event.respondWith(handleRequest(event.request));
});
async function handleRequest(request) {
const url = new URL(request.url);
return new Response('Path: ' + url.pathname, {
status: 200,
headers: { 'Content-Type': 'text/plain' }
});
}
// After: Azion Functions
export default {
async fetch(request) {
const url = new URL(request.url);
return new Response('Path: ' + url.pathname, {
status: 200,
headers: { 'Content-Type': 'text/plain' }
});
}
};
`} />
#### Update Configuration Access
{
socket.send('received: ' + event.data);
});
return response;
}
return new Response('Expected WebSocket upgrade', { status: 400 });
}
};
`} />
#### Reference documentation
* [WebSocket Proxy](https://www.azion.com/en/documentation/products/build/applications/websocket/)
* [WebSocket API](https://www.azion.com/en/documentation/runtime/api-reference/websocket/)
* [Tiered Cache](https://www.azion.com/en/documentation/products/build/applications/cache/tiered-cache/)
* [Origin Shield](https://www.azion.com/en/documentation/products/secure/connectors/origin-shield/)
### 11. Migrating AI Accelerator Patterns
Fastly AI Accelerator focuses on semantic caching and acceleration for AI API traffic. On Azion, AI workloads can combine AI Inference, Functions, Cache, Real-Time Events, and Data Stream depending on whether the goal is inference execution, traffic control, observability, or response caching.
#### Key Differences
| Aspect | Fastly AI Accelerator | Azion |
| :----- | :-------------------- | :---- |
| **Primary pattern** | Semantic caching for AI API traffic | AI Inference + Functions + Cache |
| **Request control** | Service and Compute logic | Rules Engine + Functions |
| **Observability** | Logging and inspectors | Real-Time Events + Data Stream + Real-Time Metrics |
| **Model execution** | External AI APIs accelerated by Fastly | AI Inference or external AI APIs called from Functions |
#### Function Integration Example