Installation from a zip file within PowerShell
$latest_rel = invoke-restMethod https://gitlab.com/api/v4/projects/graphviz%2Fgraphviz/releases/permalink/latest
$version = $latest_rel.tag_name
#
# Download ZIP
# TODO: Should probably be using $latest_rel.assets to determine download link:
#
$progressPreference = 'SilentlyContinue'
invoke-webRequest "https://gitlab.com/api/v4/projects/4207231/packages/generic/graphviz-releases/$version/windows_10_cmake_Release_Graphviz-$version-win64.zip" -outFile $env:temp\graphviz.zip
tar.exe xf $env:temp\graphviz.zip -C $env:temp
mv "$env:temp\Graphviz-$version-win64\bin" $home\bin\graphviz
#
# Set PATH temporarily ‥
$env:path="$home\bin\graphviz;$env:path"
# ‥ or, alternatively permanently:
# add-dirToPath add-dirToPath $home\bin\graphviz