Managing dependencies Dependency groups Poetry provides a way to organize your dependencies by groups. For instance, you might have dependencies that are only needed to test your project or to build the documentation. To declare a new dependency group, use a tool.poetry.group.<group> section where <group> is the name of your dependency group (for instance, test): [tool.poetry.group.test] # This part can be left out [tool.poetry.group.test.dependencies] pytest = "^6.0.0" pytest-mock = "*" Note All dependencies must be compatible with each other across groups since they will be resolved regardless of whether they are required for installation or not (see Installing group dependencies).