Yea, it's exactly like MongoDB which is also AGPL.

Using the database doesn't impose any restrictions on your software.

Even hacking on juju to add API'S you for your client software doesn't impose restrictions on the client -- it just means you are subject to the AGPL licence source distribution rules on the patched version of Juju.

Mongo is a different beast, because the mongo client has a GPL exception which allows your code, that is linked to the mongo client, to use a different license. This is a friendly exception, that the mongo developers allowed. Without that exception everything using mongo even over the Internet would automatically also be AGPL licensed.

IADNAL, but its a matter of risk. If one uses juju in operations scripts to implement proprietary services, do you have to make those scripts available to end users? At what point does your software become "derivative" of juju? This interpretation definitely borders on FUD, buts its easier not to take the risk when other options are available.

GPL is viral and imposes restriction which you can't foresee. A recent example is the AppStore fiasco VLC had. It required a complete rewrite and additional development years to get it in the store just because the original code was GPL. Please think twice before using (A)GPL and make sure you have checked all consequences.

GPL is indeed viral, however it's viral under certain circumstances, not all. AGPL changes some of those circumstances.

I do not believe that _running_ your software on top of AGPL-licensed Juju makes one iota of difference.

The App Store is different: the restrictions the App store adds are at odds with GPL's defined freedoms. Not the same issue here.

Everything you program that uses Juju's API, automatically also gets AGPL licensed and that's a big no-go for any commercial development.