rownarts.
en

work/s3tow/

s3tow

A native macOS file manager for S3 and SFTP.

  • Native app
  • Engineering
  • Interface
  • 2026
A stack of translucent frosted acrylic slabs edge-lit against a graphite backdrop, one slab pulled slightly out

The brief

Every S3 client is either a web console that fights you or a desktop app that ships an entire browser in order to draw a list of files. We wanted the Mac app: something that opens instantly, behaves like the Finder, and stays inside the sandbox.

What we did

  • SwiftUI throughout — a Mac app that looks and behaves like one
  • AWS SigV4 signing and the S3 REST protocol implemented directly on URLSession
  • SFTP alongside S3, because real work spans both
  • No bundled CLI, no embedded browser, no background daemon

Where it landed

0third-party storage SDKs
2protocols, one interface
1process, sandboxed

Writing the protocol ourselves cost a fortnight. It bought an app that opens in under a second.

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