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creating-julia-app

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Use when you create a CLI written in Julia packages or MCP servers

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How to use this skill

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  1. Open your project in Codex.
  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
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Source SKILL.md: https://github.com/hashgraph-online/awesome-codex-plugins/blob/HEAD/plugins/AtelierArith/atelier-arith-julia-development-skills/skills/creating-julia-app/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/creating-julia-app/. Do not write files or run scripts until I approve.

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Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Creating a Julia app

Apps are Julia packages that are intended to be run as "standalone programs" (by e.g. typing the name of the app in the terminal possibly together with some arguments or flags/options). This is in contrast to most Julia packages that are used as "libraries" and are loaded by other files or in the Julia REPL.

A Julia app is structured similar to a standard Julia library with the following additions:

A @main entry point in the package module (see the Julia help on @main for details) An [apps] section in the Project.toml file listing the executable names that the package provides. A very simple example of an app that prints the reversed input arguments would be:

# src/MyReverseApp.jl
module MyReverseApp

function (@main)(ARGS)
    for arg in ARGS
        print(stdout, reverse(arg), " ")
    end
    return
end

end # module

# Project.toml

# standard fields here

[apps]
reverse = {}

The empty table {} is to allow for giving metadata about the app.

After installing this app one could run:

$ ~/.julia/bin/reverse some input string
 emos tupni gnirts

directly in the terminal. See the following link to learn more: