ColdStorage

ColdStorage is a Mac app for files that need to be kept but rarely opened. Files dragged into it are encrypted on the Mac and uploaded to S3 Glacier Deep Archive. Getting a file back starts with a request, and the app quotes the wait and the retrieval fee before anything moves.

A Swift daemon does the work in the background. It scans the files, encrypts them and uploads them as resumable multipart uploads, so an interrupted upload skips the parts that already made it to S3. The window is an Electron and React control panel that talks to the daemon over a local socket. The app never sees the encryption key, and the two source files that make that true are published so anyone can check.

It exists because Deep Archive is about the cheapest reliable storage available, but using it directly means setting up and running AWS. ColdStorage puts an app in front of it for people who don't work in AWS.

V1 works and is in private use while the multi-user paid layer gets built. The code is source-available under a Functional Source License, and every version becomes Apache-2.0 two years after release.