# Store Julia version in Manifest?

**URL:** <https://discourse.julialang.org/t/store-julia-version-in-manifest/65575>\
**Category:** Internals & Design\
**Created:** [July 30, 2021, 11:51pm UTC](https://discourse.julialang.org/t/store-julia-version-in-manifest/65575 "2021-07-30T23:51:25Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![marius311](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/marius311/32/3953_2.png) [@marius311](https://discourse.julialang.org/u/marius311)\
**Post date:** [July 30, 2021, 11:51pm UTC](https://discourse.julialang.org/t/store-julia-version-in-manifest/65575/1 "2021-07-30T23:51:26Z")

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I wonder whether it would make sense to store the Julia version in the Manifest.toml as well? I’m aware one can put a Julia compat entry in the Project.toml, but my understanding is compat entries kind of serve a different purpose, whereas the Manifest is supposed to provide an entirely specified and reproducible environment, in which case I think you’d want the Julia version in there too.

Eg I just ran into a case where I was revisiting some old code, and even with the exact package versions instantiated from the Manifest I had saved back in the day, I had to downgrade Julia to the version I was using then for it to work without error, which in this case I had to do by guessing since it wasn’t recorded anywhere.

I guess one question is what should happen if you load a Manifest with a different Julia version? Perhaps a warning should be issued but otherwise things should continue, since most likely it should still work (my case is probably an exception, not the rule). Then perhaps a `resolve` should actually update the Manifest with the currently running Julia version?

Couldn’t find this discussed anywhere so figured I ask here before maybe filing an issue.

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**Author:** ![giordano](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/giordano/32/2166_2.png) [@giordano](https://discourse.julialang.org/u/giordano)\
**Post date:** [July 31, 2021, 12:39am UTC](https://discourse.julialang.org/t/store-julia-version-in-manifest/65575/2 "2021-07-31T00:39:02Z")

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> [@marius311](#):
>
> I wonder whether it would make sense to store the Julia version in the Manifest.toml as well?

I think Julia v1.7 does it?

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**Author:** ![marius311](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/marius311/32/3953_2.png) [@marius311](https://discourse.julialang.org/u/marius311)\
**Post date:** [July 31, 2021, 2:23am UTC](https://discourse.julialang.org/t/store-julia-version-in-manifest/65575/3 "2021-07-31T02:23:44Z")

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So it does, love when my issues are resolved before I even ask them 🙂