Therefore I think if I use the GPL the ideas will flourish but my project will become a footnote in the history of that, whereas if I use BSD license I think it would live long and prosper. I think the Boost guys went with BSD style license instead of GPL style license because it gave them the best chance at being the de-facto libs for the things it covers. For example, you certainly found it useful to be able to choose your own license, and I suppose may not have used Boost graph libs if their license terms forced you to use Boost's own license (as you want a GPL style license).

Ideally my project could receive the support of proprietary vendors as well as the public community, as I think this gives it the best chance. 
* Metasploit had a BSD license and when bought by Rapid7 the source remains open and the community very active (although there is an extra closed source component - pro version). A pentester can still use everything they need for free.
* Nessus had a GPL license and when bought by Tennable they closed the whole thing and the community died, A pentester can't get any functionality from it without a very expensive license.
* Nipper was written by one of my friends/colleagues and released under GPLv3. Most of the security community use it to analyse firewalls but no-one contributed code or even money for new devices so he can support them etc. (even though a huge amount of money was being made by using it). Because of this he had the choice of either stagnating the project or turning it into a company, which is now very successful and all the developments he dreamed of are being done. I believe he would have had more code support and therefore perhaps have stayed open if he had originally released with a BSD license, but no-one really knows what alternative histories would have looked like.


I will have to think a bit more about this. Its quite likely that in future I'd want to share datastructures with the graph service in future, or even expose a direct API whereupon the GPL might start to 'infect' the rest of the project.
Given what we have discussed I therefore have to decide between 3 options:
1. Don't worry about all the above thoughts, just go ahead and GPL the lot so as to go back to not worrying about which components have which license

2. Do worry about the above, maintain two versions of the graph service with different licenses, hope future architectural decisions don't land me in the GPL trap.
3. Do worry about the above, write my own BGL wrapper and hope its not too hard to make/maintain, but still retain ability to choose the license for all my code (and not worry about which bits have which license).

As the only person I know of who has written a python wrapper for BGL, would you be able to give me a few words about how 'hard' it is? Was this a fairly trivial part of graph-tool or a pretty huge part of the work?

Thanks very much for your time,

Tim