Webhooks are a powerful tool for automating workflows and integrating different applications by sending data from one app to another on certain events. However, they require a public URL which can be problematic for testing or development purposes. Smee.io is a payload delivery service that proxies payloads from the webhook source and transmits them to a locally running application. While it was designed for GitHub, customizing it for other services may be necessary. This article discusses how to customize smee.io for use with Slack webhooks, which includes addressing limitations such as lack of path forwarding support and inability to respond with a challenge during the ownership verification phase. The author recommends forking or cloning the smee.io repo and building upon it locally before deploying any changes.