Fréderic, Hal, Nicolas, Thank you for taking the time to educate me. I agree that this solution doesn't scale or maintain well in the general case. As distribution maintainers you certainly have my respect. Now let me make the instrument-side problem clearer: Instrument makers don't necessarily want invisible bug fixes. Say I have an instrument and I run acceptance tests on it. What I am guaranteeing to the customer is that all the instruments of this function match. If there is a bugfix somewhere in the chain, (or worse a BUG!) that creeps in via the shared library mechanism, then the semantics of the library change, and suddenly various instruments on different systems with and without the fix may not match anymore. How can I avoid fixes to shared libraries affecting the behavior of an instrument ? Static linking seems a solution, albeit an ugly one. Edmund On Sun, Jul 27, 2008 at 9:15 PM, Hal V. Engel <hvengel@xxxxxxxxxxx> wrote: > On Sunday 27 July 2008 11:25:32 am Frederic Crozat wrote: >