# Upgrade from pre 1.0 PackageCompiler

PackageCompiler.jl got significantly changed for the 1.0 release. This page is intended to provide some guidance in transitioning from the previous PackageCompiler to PackageCompiler 1.0. PackageCompiler 1.0 has quite extensive documentation which, in addition to this page, contains useful information when upgrading.

If you want to keep using the older version of PackageCompiler you can add an entry

[compat]
PackageCompiler = "0.6"

### General notes

• PackageCompiler.jl now requires Julia 1.3.1.
• There is no command-line interface anymore

### Sysimages

• The function to create a sysimage is now called create_sysimage instead of compile_incremental.
• The tests of packages are no longer automatically run to gather precompile statements. If you wish to keep using package tests you can see an example of that in the documentation for creating a sysimage.

### Executables

• The function to create an executable is now called create_app instead of build_executable.
• The julia_main function for executables should no longer take any arguments (just access the global ARGS) and no longer need to be annotated with Base.@ccallable.
• The code for an executable need to be structured as a package, that is, with a Project.toml file and a src/Package.jl file etc.
• See https://github.com/JuliaLang/PackageCompiler.jl/tree/master/examples/MyApp for an example of the source code for an executable.