What a Real Guarantee Requires

The minimum requirements

To prevent duplicate side effects, a system must:

1. Establish durable state before executing effects

• The system must remember what it has seen
• Memory is not enough
• Logs are not enough

2. Bind execution to that state atomically

• Either the effect happens and state updates
• Or neither happens
• No in-between

3. Reject or short-circuit replays deterministically

• Every retry must hit the same decision point
• No timing-based logic
• No best-effort checks

4. Operate outside application process memory

• Processes crash
• Containers restart
• Horizontal scaling is normal

Why middleware alone fails

Most webhook handlers run:

• inside web servers
• behind frameworks
• with business logic interleaved

This makes it extremely hard to:

• reason about atomicity
• guarantee ordering
• control execution boundaries

Idempotency bolted onto handlers is fragile by default.

Where a gateway fits

A gateway sits before application logic and:

• absorbs retries
• deduplicates events
• establishes durable intake state
• controls execution flow

This is not an implementation detail.
It is a boundary decision.

Once retries pass into business logic, safety is already compromised.

What WebhookGate guarantees

WebhookGate guarantees:

• no duplicate side effects for the same webhook event
• regardless of retries, concurrency, or crashes

WebhookGate does not:

• promise exactly-once delivery
• fix unsafe downstream code
• run business logic for you

It enforces the boundary that makes safety possible.

What to do next

If webhook failures matter in production:

• read how teams integrate WebhookGate
• evaluate it in a pilot
• test it against real failure modes

Understanding the problem is step one.
Eliminating it requires a system designed for reality.