Clone the git repo with some git client
Download and install the latest installer build
Go to setup.py in the git checkout and run C:\Program Files\Gaphor\bin\python.exe setup.py run.

2. Use a Full MSYS2 Environment

Download msys2 64-bit from https://msys2.org
Follow instructions on https://msys2.org
Execute C:\msys64\mingw64.exe
Run pacman -Syu to update packages
Run pacman -S git to install git
Run git clone https://github.com/gaphor/gaphor.git
Run cd gaphor/win_installer to end up where this README exists.
Execute ./bootstrap.sh to install all the needed dependencies.
Now go to the source code cd ../
To run Gaphor execute python3 setup.py run

Creating an Installer

Simply run ./build.sh and both the installer and the portable installer should appear in this directory.

You can also run the build using a specific git version:

Pass a git tag with: ./build.sh release-1.0.0
Pass a git commit hash with: ./build.sh a5d3e53406fadd1fe089aa995b650949256d4981
Pass nothing to build master

Note: build.sh clones from the local repository and not from GitHub so any commits present locally will be cloned as well.

Updating an Existing Installer

We directly follow msys2 upstream so building the installer two weeks later might result in newer versions of dependencies being used. To reduce the risk of stable release breakage you can use an existing installer and just install a newer Gaphor version into it and then repack it:

./rebuild.sh gaphor-1.0.0-installer.exe [git tag / commit]