What Are Virtual Webhooks? How They Differ From Sync-Based Webhooks
January 22, 2026
When SaaS teams say 'webhooks,' they often mean very different things. Virtual webhooks emit events when a change is detected, while sync-based webhooks emit events when a data sync completes.
That difference affects freshness, complexity, and whether you still need polling logic in your app.
This post breaks down:
- what virtual webhooks actually are,
- how they differ from sync-based webhooks, and
- why the distinction matters for product architecture.
Native webhooks (the baseline)
A native webhook is simple:
- The source system detects a change
- It pushes an event to your endpoint
- Your app reacts immediately
Stripe payments, GitHub commits, Shopify orders. This is the ideal model.
The problem is coverage. Most SaaS APIs don't offer native webhooks for many (or any) objects.
Virtual webhooks: poll, detect, deliver
A virtual webhook simulates native webhook behavior for systems that don't support it.
Under the hood, the platform:
- Polls the source API on a schedule
- Detects changes (timestamps, deltas, cursors, etc.)
- Pushes a webhook event to your app when changes are found
From your app's perspective:
- You subscribe once
- You receive webhook events
- You don't run cron jobs or polling infrastructure
Crucially, a virtual webhook is designed to replace polling, not disguise it.
Sync-based webhooks: sync first, notify later
Many platforms also emit webhook events, but their model is different.
In a sync-based webhook architecture:
- The platform runs a scheduled sync
- Data is written into a vendor-hosted store
- A webhook is emitted based on that stored copy
Often, the webhook:
- signals that something changed, and
- requires your app to fetch updated data in a follow-up call
A simple comparison
| Aspect | Virtual webhooks | Sync-based webhooks |
|---|---|---|
| Trigger | Change detection | Sync completion |
| Requires vendor data store | Not inherently | Yes |
| Requires follow-up fetch | Often no | Often yes |
| Freshness tied to | Polling interval | Sync schedule |
| Replaces polling jobs | Yes | Not fully |
This is common in systems built around replication, warehousing, or cached APIs.
The key difference: Virtual webhooks deliver change events directly; sync-based webhooks notify you that a sync occurred.
Why this difference matters
1. Extra API calls
With sync-based webhooks, a notification often triggers another read to fetch the actual data.
Virtual webhooks can deliver updated records directly in the webhook payload, depending on the platform's architecture.
2. Data freshness
Sync-based webhooks are bounded by:
- sync frequency
- queue delays
- storage lag
Virtual webhooks are bounded only by the polling interval and detection logic.
3. Architecture complexity
Sync-based models require you to reason about:
- sync state
- replica consistency
- 'did this webhook reflect the latest sync?'
Virtual webhooks collapse this into a single event stream.
4. Data ownership
Sync-based systems depend on vendor-hosted replicas.
Virtual webhooks can be implemented without storing customer data at rest, depending on the platform's architecture.
When virtual webhooks are the better fit
Virtual webhooks are a better choice when:
- the source API lacks native webhooks
- your product depends on timely updates
- you want to eliminate polling infrastructure
- you don't want to reason about sync state or replicas
The takeaway
Not all 'webhooks' are the same.
If a webhook is emitted because data was synced, you're still building on a batch model.
If a webhook is emitted because a change was detected, you're much closer to real-time behavior—even when the source system doesn't support webhooks at all.
That's the difference virtual webhooks are meant to solve.