Using the Herwig bootstrap script

Out of the box

For a fully automated installation, download the current bootstrap script from, then run

chmod +x herwig-bootstrap
./herwig-bootstrap /where/to/install/herwig

In the following we will call the location of the installation ${HERWIGPATH}. For a quicker installation you can supplement the -j option, for example

./herwig-bootstrap -j 4 ${HERWIGPATH}

After the bootstrap script completes, you can

source ${HERWIGPATH}/bin/activate

to set all required environment variables consistently. To go back to your default environment, run


To see a full list of options for the installation process run

./herwig-bootstrap --help

Selectively rebuild

The script will skip over packages that it has already installed successfully. To update a package anyway, you can remove the lock file for package NNNNN from the source location

rm ${HERWIGPATH}/src/herwig_bootstrap_NNNNN_done

and re-run

./herwig-bootstrap -j 4 ${HERWIGPATH}

Use your own pre-installed packages

Herwig builds on a number of freely available libraries and programs from 3rd parties. If you want to install some of these packages on your own or you might not need them for your Herwig build you can switch them off during installation. To switch off a package use the


switch. If you have any package already installed you can tell the bootstrap script its location by adding


to the former switch. Your installation now may look like the following

./herwig-bootstrap -j 4 --without-boost --boost-location=where/boost/is --without-vbfnlo ${HERWIGPATH}

If you chose to link against any pre-installed packages make sure that you have read Prerequisites of the Herwig program.