Send is a web service for sharing files through a link that expires automatically. According to the project, files are end-to-end encrypted and what you share does not stay online indefinitely. It is a Node.js server application with optional Redis and S3-compatible storage, aimed at people and organisations that want to run their own file-sharing service. The ffsend command-line client is also compatible.
Send is a community fork of Firefox Send, which Mozilla discontinued. The fork removes the Mozilla and Firefox branding so the software can be self-hosted. The project is maintained by an individual developer in the Netherlands, with no legal entity behind it, and is licensed under the Mozilla Public License 2.0. The developer also runs a public instance and publishes a list of instances run by others. Because you can install Send on your own servers, you decide where files are stored and for how long. No formal organisation or support contract stands behind the project, which is a consideration for business-critical use.