# When does a package activation/instantiation trigger a build?
**URL:** https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649
**Category:** General Usage
**Tags:** package
**Created:** [July 25, 2020, 12:52am UTC](https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649 "2020-07-25T00:52:00Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)
#### Post date: [July 25, 2020, 12:52am UTC](https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649/1 "2020-07-25T00:52:00Z")
When is a build triggered for a package that has a deps/build.jl?
It is not triggered when I do activate/instantiate. Is there an automatic build?
Or is an explicit `build()` required?
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### Author:  [@Tamas\_Papp](https://discourse.julialang.org/u/Tamas_Papp)
#### Post date: [July 25, 2020, 7:45am UTC](https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649/2 "2020-07-25T07:45:45Z")
[https://julialang.github.io/Pkg.jl/dev/managing-packages/#Building-packages-1](https://julialang.github.io/Pkg.jl/dev/managing-packages/#Building-packages-1)
> The build step of a package is automatically run when a package is first installed. The output of the build process is directed to a file. To explicitly run the build step for a package, the `build` command is used:
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### Author:  [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)
#### Post date: [July 25, 2020, 3:07pm UTC](https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649/3 "2020-07-25T15:07:46Z")
That is correct information for a “local” install. But on [mybinder.org](http://mybinder.org) the mechanism appears to be different.
I had to use a special script: [Mechanism for build() in mybinder? - #2 by PetrKryslUCSD](https://discourse.julialang.org/t/mechanism-for-build-in-mybinder/43644/2)
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### Author:  [@PetrKryslUCSD](https://discourse.julialang.org/u/PetrKryslUCSD)
#### Post date: [July 25, 2020, 3:17pm UTC](https://discourse.julialang.org/t/when-does-a-package-activation-instantiation-trigger-a-build/43649/4 "2020-07-25T15:17:48Z")
Perhaps the process of opening a package on mybinder is not really a “package installation”?
That would explain why build is not run. Could be that it is more like activating a local repository without
it being added as a package.