Outpost is an open-source outbound webhooks and event destinations infrastructure that provides a scalable, reliable way to deliver events to users' infrastructure without needing to build the capability from scratch. It acts as an event relay between backend systems and user-defined event destinations such as webhooks, queues, and event buses, with at-least-once delivery guarantees and full observability. Outpost is self-hostable, open source under the Apache 2.0 license, and compatible with existing event models, making it a solution for SaaS and API platforms that need to push events to customer-defined destinations while maintaining reliability, retry logic, and great developer experience out of the box.