Your package manager of choice might be a little bit behind for the version of leveldb we're using. Specifically, Ubuntu prior to 13.04 is behind. To install manually:
Make sure you are using at least go1.1.1.
Download leveldb version 1.9 or higher:
wget https://leveldb.googlecode.com/files/leveldb-1.9.0.tar.gz
tar xzvf leveldb-1.9.0.tar.gz
cd leveldb-1.9.0 && make
This directory is your LEVELDB_HOME.
Then add the following lines to your .bashrc so go can use them to link leveldb code
export CGO_CFLAGS="-I$LEVELDB_HOME/include"
export CGO_LDFLAGS="-L$LEVELDB_HOME"
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$LEVELDB_HOME
Now run
go get github.com/jbooth/maggiefs/mfs go install github.com/jbooth/maggiefs/mfs
and you'll have the maggiefs binary installed.