What’s lockfile in the context of dependency

content

a file automatically generated by package manager to record the exact versions of dependencies that are installed (or, dependencies needed to build something in the context of build systems)
process:
- define desired versions in manifest files (like pyproject.toml, package.json)
- build system or package manager resolves manifest files
- the exact versions of dependencies are written into lockfiles
lockfiles could be committed into version control