Outpost

What is Outpost?

Outpost is open-source infrastructure for delivering events to user-preferred destinations such as outbound webhooks and several event/queue systems. It’s designed to help applications send event notifications reliably, with a focus on reducing operational complexity compared with building and maintaining webhook delivery logic yourself.

Outpost can be used either as a managed service by Hookdeck or self-hosted from open-source code. Its core purpose is outbound event delivery: you publish events and Outpost routes them to configured destinations using topics/subscriptions and delivery guarantees.

Key Features

• At-least-once delivery guarantees: Messages are delivered at-least-once, aiming to prevent lost events.
• Topic-based subscriptions: Publish/subscribe patterns to make it easier to map event types to destinations.
• Automatic and manual retries: Configure automatic retries, or trigger retries via an API or the user portal.
• Multiple delivery destinations: Support for webhook delivery plus event destinations such as AWS SQS, RabbitMQ, Pub/Sub, EventBridge, Kafka, and more (as listed on the page).
• Multi-tenant support: Run multiple tenants on a single Outpost deployment.
• Developer portal and destination controls: View metrics and manage, debug, and observe event destinations.
• OpenTelemetry support: Includes OpenTelemetry traces, metrics, and logs.
• Idempotency and delivery headers: Provides idempotency headers, timestamps, and signatures (including signature rotation), with an opt-out mechanism.
• Deploy your way (managed or self-hosted): Delivered as a Go binary or Docker image for self-hosting; the same Outpost is used whether managed or self-hosted.

How to Use Outpost

1. Choose a deployment model: Start with the managed service (“Get started”) or run the open-source self-hosted version using the provided distribution (Go binary or Docker image).
2. Define destinations: Configure one or more delivery targets (for example, a webhook endpoint, or a queue/bus destination).
3. Set up topics and subscriptions: Create mappings between event topics (event types) and which destinations should receive them.
4. Publish events: Send events using the Outpost API or by publishing into a queue that Outpost can read from.
5. Operate and troubleshoot: Use the user portal to observe delivery metrics, manage destinations, and trigger retries when needed.

Use Cases

• Reliable outbound webhook delivery for app events: Route application events (e.g., user.created, order.created) to webhook destinations with at-least-once delivery and retries.
• Queue-based publishing to decouple producers from delivery: Publish events into a queue and configure Outpost to read from it, then deliver to downstream systems.
• Fan-out across multiple event destinations: Send the same or related event topics to different destinations (e.g., a webhook plus a message queue/bus) using topic/subscription configuration.
• Multi-tenant event delivery: Serve multiple tenants from one Outpost deployment, isolating delivery configuration per tenant.
• Debugging and operational visibility for event plumbing: Use the portal to track destination status and delivery outcomes, and use manual retries when failures occur.

FAQ

• Can I run Outpost myself, or do I need the managed service? Outpost is available as both a managed service and as open-source software for self-hosting.

• How does Outpost handle retries? It supports automatic retries and also allows manual retries via an API or the user portal.

• What delivery guarantee does Outpost provide? The page states that messages are delivered at-least-once.

• Does Outpost provide observability features? Yes. It includes OpenTelemetry support for traces, metrics, and logs, and it provides a developer portal for metrics and destination observation.

• How does Outpost sign and secure deliveries to webhooks? The page mentions timestamp and signature headers (with signature rotation) and idempotency headers, along with an opt-out mechanism.

Alternatives

• Roll your own webhook dispatcher: Build custom webhook delivery, retries, and security. This shifts the operational and reliability burden onto your application team.
• Generic event/queue systems without an outbound delivery layer: Use platforms that store/transport events (queues or buses) and implement your own consumer logic to push to webhooks/destinations.
• Other managed webhook/event delivery services: Use a hosted service that routes events to webhook endpoints; compare based on how they handle retries, delivery guarantees, and multi-destination delivery.
• Self-hosted event routing components: Look for open-source or self-hostable components focused on event routing from producers to destinations, especially those with subscription/topic semantics and operational tooling.