Ask HN: A software for forwarding data to a remote server?

Looking for a local agent (software) that would forward data to a remote endpoint (https etc), and/or act as a proxy to connect a local database to a remote api/server.

Needs to work behind a NAT firewall and not require a static ip/typical VPN.

Example, sending any new files in a directory, or forwarding data from a connected serial/usb device, such as a sensor.

Kind of similar to Elastic Beats, or a DataDog agent, but wasn't sure if those would be the best solution.

Semi-technical users would install and run, so prefer not to use manual solutions, (configuring ssh server or rsync directly etc).

Preferably open source so can make changes as needed. But would consider a closed source/retail agent if it was configurable and lightweight. Would also consider two different agents to handle different use cases.