Authoring a fyr-package

A sibling fyr-package composes the two halves of the pyro contract: declare a dependency group, then materialize it.

my_initialize <- function() {
  pyro::write_group_to_pyproject(
    name = "mypkg",
    deps = c("pillow==11.1.0", "requests==2.31.0")
  )
  pyro::initialize_python(groups = "mypkg")
}

The split between the two calls is deliberate. write_group_to_pyproject() declares intent and stops there, it returns without touching uv, Python, or the network, so it is safe to call repeatedly and cheap to compose. Nothing is installed until initialize_python() runs. That separation is what lets several wrappers each register a group and then sync exactly once, instead of every wrapper triggering its own resolve mid-chain.

deps is where pin ownership is decided. For a group pyro already blesses (reportifyr, presentifyr), omit it and the pins are read straight from the bundled reference spec, the wrapper inherits whatever pyro ships and stays in lockstep with it. Pass deps explicitly and those become the project’s pins, with pyro staying out of the way. A third-party app has no blessed entry to fall back on, so it must always supply deps.