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Since in newer versions of uv (specifically uv 0.10.5+, which we haven't yet updated to) the default link mode has changed from `hardlink` to `clone` (aka reflink), and reflinks are slower in some environments (such as Heroku's build system). See: astral-sh/uv#18259 Even if the uv default ends up being changed back to hard links again, it seems worth us explicitly requesting that link mode, given that we know it's the best mode for our use-case. GUS-W-21429394.
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## heroku/python ### Changed - Updated pip from 25.3 to 26.0.1. ([#508](heroku/buildpacks-python#508)) - Updated uv from 0.10.1 to 0.10.7. ([#518](heroku/buildpacks-python#518)) - Explicitly configured uv to use hard links to maintain the behaviour of previous versions. ([#519](heroku/buildpacks-python#519))
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Since in newer versions of uv (specifically uv 0.10.5+, which we haven't yet updated to) the default link mode has changed from
hardlinktoclone(aka reflink), and reflinks are slower in some environments (such as Heroku's build system).See:
Even if the uv default ends up being changed back to hard links again, it seems worth us explicitly requesting that link mode, given that we know it's the best mode for our use-case.
GUS-W-21429394.