Debug Taskgraph

Debug Taskgraph

There are several approaches you could take when you need to debug changes in Taskgraph.


It’s also possible to use the built-in Python debugger, pdb. Simply add calls to pdb.set_trace() and run the taskgraph binary as normal. Note that as with print debugging, you’ll want to ensure that breakpoints are only triggered on the tasks you are aiming to debug:

def some_transform(config, tasks):
    import pdb
    for task in tasks:
        # Note "name" is not a standard field, use whatever field
        # is appropriate here.
        if task["name"] == "my-task":


Debugpy is the Python debugger that comes bundled with VSCode. But it can be used with other editors as well, such as Neovim via the nvim-dap-python plugin. The advantage of debugpy is that you can set breakpoints directly via your editor (so you don’t need to edit your source). You can trigger new runs from within your editor as well.

How to setup debugpy varies editor by editor and is out of scope for these docs. But typically there will be a way of defining a “launch config”. For taskgraph it should look similar to:

    "name": "Taskgraph Full",
    "type": "python",
    "request": "launch",
    "program": "/path/to/bin/taskgraph",
    "args": ["full"],
    "console": "integratedTerminal",
    "justMyCode": false

Make sure to adjust “program” to point to your taskgraph binary. Also be sure to tweak args as you see fit. See Useful Arguments for more information on available arguments.