git-annex/doc/install/fromsource.mdwn

So you want to build git-annex from source. This is encouraged for
users with experience building code from source. But the build may
require some care and feeding. This page will start with the easy
methods and work up to the harder ones.

## prerequisites

Start by installing the 
[Haskell Platform](http://hackage.haskell.org/platform/).

In Debian, this is as simple as:

	sudo apt-get install haskell-platform

## downloading the source code

The easiest way is using git; see [[download]] or just:

	git clone git://git-annex.branchable.com/ git-annex

Or, you can use cabal to get the source code:

	cabal update; cabal unpack git-annex

## building from source on Debian

This is the method used by git-annex's author, and so it's the one most
likely to work without problems.

First, install everything git-annex needs to build:

	sudo apt-get build-dep git-annex

Now you can build git-annex by running either `make` or `cabal build`
inside the source tree.

## minimal build with cabal

This can be done anywhere, and builds git-annex without some features that
require C libraries, that can be harder to get installed. This is plenty to
get started using it, although it does not include the assistant or webapp.

Inside the source tree, run:

	cabal configure -f"-assistant -webapp -webdav -pairing -xmpp -dns"
	cabal install --only-dependencies
	cabal build
	PATH=$HOME/bin:$PATH
	cabal install --bindir=$HOME/bin

Be warned that this involves building a lot of Haskell libraries from
source, and so it has a lot of moving parts, and it's not uncommon for it
to be broken from time to time.

## full build with cabal

To build with all features enabled, including the assistant and webapp,
you will need to install several C libraries and their headers,
including libgnutls, libgsasl, libxml2, and zlib. How to do that for
your OS is beyond the scope of this page. 

Once the C libraries are installed, run inside the source tree:

	cabal configure
	cabal install --only-dependencies
	cabal build
	PATH=$HOME/bin:$PATH
	cabal install --bindir=$HOME/bin

## EKG

When building with cabal, you can optionally enable the 
[[EKG monitoring interface|ekg]]. This is great for debugging resource
usage problems. Just pass `-f+EKG` to `cabal configure`