We have a poetry project with a pyproject.toml file like this: [tool.poetry] name = "daisy" version = "0.0.2" description = "" authors = [""] [tool.poetry.dependencies] python = "^3.9" pandas = "^1.5.2" DateTime = "^4.9" names = "^0.3.0" uuid = "^1.30" pyyaml = "^6.0" psycopg2-binary = "^2.9.5" sqlalchemy = "^2.0.1" pytest = "^7.2.0" [tool.poetry.dev-dependencies] jupyterlab = "^3.5.2" line_profiler = "^4.0.2" matplotlib = "^3.6.2" seaborn = "^0.12.1" [build-system] requires = ["poetry-core>=1.0.0"] build-backend = "poetry.core.masonry.api" When I change the file to use Python 3.11 and run poetry update we get the following error: Current Python version (3.9.7) is not allowed by the project (^3.11). Please change python executable via the "env use" command. I only have one env: > poetry env list daisy-Z0c0FuMJ-py3.9 (Activated) Strangely this issue does not occur on my Macbook, only on our Linux machine. Continue reading...