I have been thinking about using Sleepycat Software's Berkeley DB XML (BDBXML), the speedy open source XML database behind Kimbro Staken's XPath-happy prototype blogware, Syncato.  BDBXML license was confusing to me, particularly the word "redistribution", so I contacted them yesterday to find out if I could use it for free.

My situation is a common one in that I will have a single server driving several websites and web services, some of which will be commercial.  More servers might be added later, but still located at a single data center (ServerMatrix).  BDBXML license allows free use under this situation.  But the software that runs on my server(s) is being written at home which is in a different state.  Since my development machine is in California and my production server(s) are in Texas, I am in fact redistributing whenever I upload my software to the server(s), violating free use under BDBXML license.

Liz Pennell, Account Executive at Sleepycat Software, confirmed this but, recognizing that this might discourage developers from developing software based-on their new product, they graciously granted me free license.

Hi, Don,

I'm sorry for the delay in responding to you, but I wanted to discuss your case with some of my colleagues here.

In fact, if the development is at your home address and the hosting server is at a different postal address, the use you contemplate would typically be considered a redistribution event under the terms of our public license. As such, in the interests of applying the rules even-handedly across our user base, we'd need to specifically permit that use rather than just wink at it, if that makes sense.

However, I agree with you that this sort of use at least in spirit comports with the public license terms, as the software is only installed and performing useful work at a single physical site. It's also true that DB XML is still a young product, and we'd like to do what we can to promote its wider adoption.

Therefore, in this specific case given all the circumstances as detailed, I'd be willing to grant you a limited single-site exception to clause 3 of Sleepycat's public license, and permit your use, as described below, at no charge.

Since I knew my situation is far from unique, I asked Liz whether this exception was a general exception (?!?).  Her reply was:

I'm reluctant to commit to making this exception broadly into the future, but it's not something you need to keep secret. If an individual web site developer came to us at this point in the product's life, and described the kind of use that you're considering, we would be very likely to make the same call for the same reasons.

However, it wouldn't be prudent to assume that this will always be so, and we'd need to make the explicit judgment on a case-by-case basis every time.

There you have it, a Selective Early-Bird Special of sort.  If you are a developer in a similar siutation as me, you know what you should be doing right now.  Here is the e-mail address.

I have a feeling that Sleepycat's mailboxes will be full by Monday.  Sorry to wake you, Sleepycat.  Heehee.

Update – 2004/02/19:

Here is an update from Liz on the license which made a lot of sense to me:

Since nothing ever dies on the Net, I thought it was important to get back to you on the subject of qualification for free use of our software under Sleepycat's public license. My interpretation of the public license when you and I had our original e-mail exchange was actually too strict.

In fact, "redistribution" happens when a copy of Berkeley DB is installed *for actual use* on more than one physical site. In practice, this means that developers may build apps at multiple sites, or at a different site from where the application will be installed, because during the development cycle the application is not installed for actual use. If the application is installed for actual use at a single physical site, it qualifies for free use of Berkeley DB under the public license, regardless of where it may have been developed.