# IMQOptions.safeDeliveryTtl property · @imqueue/core

Source: https://imqueue.org/api/core/latest/core.imqoptions.safedeliveryttl/
Published: 2026-08-04
Author: @imqueue maintainers (https://github.com/imqueue)
Package: @imqueue/core 3.3.2 — generated reference, not hand-written

Lease deadline (in milliseconds) stamped onto the worker key when safeDelivery moves a message out of the queue, and the interval on which the watcher sweeps for expired keys. A worker key still present once its deadline has passed is treated as abandoned, and its message is moved back onto the main queue.

This is a recovery deadline for an abandoned hand-off, not a processing deadline. The key is released when the message is dispatched, so a slow handler is neither interrupted nor re-queued for taking too long, and raising this value extends no protection over long-running work — tune it for how quickly an abandoned message should come back.

**Signature:**

```typescript
safeDeliveryTtl?: number;
```

## Default Value

5000

## Remarks

This value applies whether or not [IMQOptions.safeDelivery](https://imqueue.org/api/core/latest/core.imqoptions.safedelivery/) is on: it always sets the period of the watcher's maintenance sweep, which also drives the [IMQOptions.cleanup](https://imqueue.org/api/core/latest/core.imqoptions.cleanup/) pass. Setting it to `null` or `undefined` disables that interval altogether, so neither lease recovery nor cleanup runs.

In safe-delivery mode it additionally sets the reader's blocking-pop timeout to half the TTL, with a 100 ms floor, after which the reader regenerates the lease and blocks again. Very small values therefore increase Redis round-trips without further reducing latency.