Install

Prove and Tasks are Python packages on PyPI. Each installs with pip into a virtual environment and runs on macOS or Linux. Every other page in these docs starts from here.

Python

Tool	Package	Python
Prove	`poisson-prove`	3.11 or later
Tasks	`poisson-tasks`	3.11 to 3.13

Check yours with python3 --version. Python 3.11, 3.12 or 3.13 runs both.

A virtual environment

Make a virtual environment first: Homebrew’s Python and current Debian and Ubuntu refuse a pip install into the system Python.

python3 -m venv .venv && source .venv/bin/activate

Install

Install the tool you need. Each is one package.

pip install poisson-prove

pip install poisson-tasks

Some routes need an extra, and the page for that route gives it:

Extra	What it adds	Where it is used
`poisson-prove[modal]`	the Modal client, for sweeps in containers on your own Modal account	Modal
`poisson-prove[agent]`	OpenTelemetry capture of your agent’s spans	Your own agent
`poisson-tasks[prove]`	Prove beside Tasks, for the route that runs tasks under Prove	Under Prove

Installing Tasks also installs verifiers, and verifiers installs commands of its own beside poisson-tasks. A bare init is verifiers’ command. This package’s is poisson-tasks init.

Trace is not installed from PyPI yet. Its own page gives the install from a clone.

Check

Tasks prints its version, the version of verifiers it runs on, and Python’s.

poisson-tasks --version

Output1 line · exit 0

poisson-tasks 0.4.1 (verifiers 0.3.1, Python 3.11.7)

Prove’s first command writes the spec of its keyless example, which is where its first run starts.

poisson-prove init --example

Output2 lines · exit 0

ok  wrote prove.toml: a sweep of the keyless mock agent, 9 conditions x 194 replicates
  next: poisson-prove sweep

Next is the first run: Prove’s quickstart, or the first run that opens Tasks.