Description:

A practical look at how Mac developers can add license keys, device activation, and offline validation without building the whole licensing system from scratch.

Keylight

Tags:

swift macos indiedev licensing security saas programming

I build Mac apps, and one thing I kept running into was licensing.

Not the fun part.

The annoying part.

You ship a paid app outside the App Store, then suddenly you need to answer questions like:

How do I issue license keys?

How do I know if a key is valid?

How do I stop one key from being shared everywhere?

What happens when the user is offline?

What happens after a refund?

Where do I store the license on macOS?

How do I support trials without building a second system?

At first, licensing looks simple.

You imagine a table like this:

license_key | email | status

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Then your app sends the key to your server and gets back:

{ "valid" : true }

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That works for a…