package opam-lock

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Locking of development package definition dependency versions


Dune Dependency





opam-lock: restrict opam file to describe a precise build environment

This small opam plugin can rewrite opam package definition files to emulate the behaviour of so-called "lock files" present in many package managers.

It reads opam files, extracts the precise set of their dependencies that is currently installed, as well as pins and non-installed optional dependencies, and writes back a <name>.opam.locked file that enforces this set and has the corresponding pin-depends:.

You can then use opam install <name>.opam.locked to get the package installed with the precise dependencies, including transitive dependencies, that it had in the original system.

Option --direct-only can be used to only lock direct dependency versions rather than the whole tree.

Note that the locked opam file adds conflicts to uninstalled optional dependencies, but not recursively: it therefore guarantees the same dependencies get installed, up to potentially some of their optional dependencies.

This project is currently in early beta.


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