pyvenv.cfg reference

Every environment contains pyvenv.cfg at its root. CPython’s site machinery reads it at startup to detect the environment and locate the base installation. tn-venv writes the standard keys plus a small set of documented extensions; unknown keys are ignored by consumers.

Example

home = C:\Python314
implementation = cpython
version_info = 3.14.7
include-system-site-packages = false
version = 3.14.7
prompt = 'my-project'
executable = C:\Python314\python.exe
base-executable = C:\Python314\python.exe
command = C:\Python314\python.exe -m tn_venv .venv --prompt my-project
tn-venv = 0.1.1

Standard keys

Key	Meaning
`home`	directory containing the base interpreter’s executable; the runtime resolves the stdlib from here
`include-system-site-packages`	`true` when created with `--system-site-packages`
`version`	`major.minor.micro` of the base interpreter
`prompt`	only written when `--prompt` was given; `repr()`-quoted, matching stdlib venv
`executable`	realpath of the base executable (stdlib venv writes this since 3.12)

Extension keys written by tn-venv

Key	Meaning
`implementation`	`sys.implementation.name` of the base interpreter (`cpython`, `pypy`, …)
`version_info`	full `major.minor.micro` (mirrors virtualenv’s key of the same name)
`base-executable`	path to `sys._base_executable` — the binary that was actually copied or linked
`command`	the full command line that created the environment, for forensics and reproduction
`tn-venv`	the version of tn-venv that created the environment

Note

home points at the directory of the base executable, per PEP 405; executable / base-executable point at the executable file. Tools that parse pyvenv.cfg (including CPython itself) rely on home first, so tn-venv never deviates from the standard there.