= Packaging =

We want to package Tahoe-LAFS for people to download and use and we want to use
3rd-party libraries. The following are our current desiderata:

 * For certain deployment targets (namely, recent Debian and recent or Long-Term Support Ubuntu), we produce a Tahoe-LAFS binary package for
   that platform, ship that package to a user using that platform, they can
   install that package, and it will work. That is: user doesn't have to
   manually satisfy any dependencies by building other packages.

   This is accomplished by adding the following clause to
   {{{/etc/apt/sources.list}}} and then running
   {{{apt-get install allmydata-tahoe}}}:

{{{
deb http://allmydata.org/debian  $DIST  main tahoe
}}}

For libraries that Tahoe uses, we have these desiderata:

 * We use the source code as it is written by upstream. That is: no patching
   required.

 * Use it as it is packaged by upstream. That is: we prefer to get a copy of
   the source code of the package as upstream prefers to distribute such
   source code, rather than by pulling from their revision control tool or so
   on.  (But we strongly prefer source packages to binary.)

 * The user doesn't have to manually resolve any conflicts (this means that
   we either have to automatically use a 3rd-party library if it is already
   installed or else we have to automatically force Tahoe to use the copy
   that it came bundled with).

 * Make it convenient for someone to use other versions of the packages that
   we use e.g. system-wide packages or newer or alternate versions, etc..

 * Bundle required libraries with the Tahoe distribution so that if someone
   downloads the distribution, moves to a desert island without a net
   connection, and then installs, it works.


== setuptools ==

We use a Python packaging tool named [http://cheeseshop.python.org/pypi/setuptools setuptools].

Advantages:

 * management of dependencies (even on platforms that don't have a native package manager);  This is the important feature.

 * integration with http://cheeseshop.python.org/ -- with setuptools we can update the [http://cheeseshop.python.org/pypi/allmydata-tahoe allmydata-tahoe metadata at the cheeseshop] automatically, and also upload packages to be distributed from cheeseshop

 * for hackers who like setuptools, this makes using Tahoe convenient and pleasant for them

Possible advantages:

 * perhaps in the future we will replace "build/configure/package/distribute/test/develop" code written in the Make language with code written in Python;  One specific instance of this is {{{./setup.py test}}} which runs the unit tests