# Why a package (Pluto here) can precompile twice in \`add\` and \`using\`?

**URL:** <https://discourse.julialang.org/t/why-a-package-pluto-here-can-precompile-twice-in-add-and-using/94699>\
**Category:** General Usage\
**Created:** [February 15, 2023, 5:53pm UTC](https://discourse.julialang.org/t/why-a-package-pluto-here-can-precompile-twice-in-add-and-using/94699 "2023-02-15T17:53:37Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![lmiq](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/lmiq/32/18314_2.png) [@lmiq](https://discourse.julialang.org/u/lmiq)\
**Post date:** [February 15, 2023, 5:53pm UTC](https://discourse.julialang.org/t/why-a-package-pluto-here-can-precompile-twice-in-add-and-using/94699/1 "2023-02-15T17:53:37Z")

</div>

Here is the example. I just created an empty new environment. Then `add Pluto` to it, which triggered precompilation. The next command `using Pluto` triggered precompilation again.

Why this can happen? I’ve seen this sort of frequently with Plots.

```julia
(@v1.9) pkg> activate .
  Activating new project at `~/Drive/Palestras/2023_CellListMap`

(2023_CellListMap) pkg> add Pluto
   Resolving package versions...
    Updating `~/Drive/Palestras/2023_CellListMap/Project.toml`
  [c3e4b0f8] + Pluto v0.19.22
    Updating `~/Drive/Palestras/2023_CellListMap/Manifest.toml`
  [d1d4a3ce] + BitFlags v0.1.7
  [944b1d66] + CodecZlib v0.7.1

... many packages

  [3f19e933] + p7zip_jll v17.4.0+0
        Info Packages marked with ⌅ have new versions available but compatibility constraints restrict them from upgrading. To see why use `status --outdated -m`
Precompiling environment...
  10 dependencies successfully precompiled in 92 seconds. 26 already precompiled.
  1 dependency had warnings during precompilation:
┌ Pluto [c3e4b0f8-55cb-11ea-2926-15256bba5781]
│ ┌ Info: 
│ │ 
│ │ Welcome to Pluto v0.19.22 🎈
│ │ Start a notebook server using:
│ │ 
│ │ julia> Pluto.run()
│ │ 
│ │ Have a look at the FAQ:
│ │ https://github.com/fonsp/Pluto.jl/wiki
│ └ 
└  

julia> using Pluto
[Info: Precompiling Pluto [c3e4b0f8-55cb-11ea-2926-15256bba5781]
┌ Info: 
│ 
│ Welcome to Pluto v0.19.22 🎈
│ Start a notebook server using:
│ 
│ julia> Pluto.run()
│ 
│ Have a look at the FAQ:
│ https://github.com/fonsp/Pluto.jl/wiki
└ 

julia> 

```