The JavaRush installer asks for administrator rights and puts about a dozen programs on your computer. Getting suspicious at that moment is normal, and it's the right reaction. Anyone who cares about their machine has every right to ask: what exactly is this program about to do to it?
This article answers that question in full, with nothing glossed over. What gets installed, where it lands, what we don't touch, what data is collected and how to undo all of it.
If you'd rather not use the installer, don't use it. The course works fine without it: the lectures walk you through installing everything you need by hand, step by step. The installer just takes the busywork off your hands.
1. Why it exists
The course needs a fair number of tools: Claude Code itself, an IDE, languages, build utilities. Each one installs differently, each has its own settings, and some of them still have to be wired together and signed in.
You can walk that path by hand, but it's a few hours of work where a small mistake is easy to make and then takes a long time to find when something refuses to start. The installer does the same thing in one run. Boring, but predictable.
2. What gets installed
Below is the full list of what will appear on your computer.
Claude Code and voice input
Claude Code CLI - the main tool of the course, the AI agent itself. It's installed by the official Anthropic installer from claude.ai, always the latest version.
Handy - a speech recognition utility. You need it to dictate tasks to the agent by voice instead of typing them. The Parakeet V3 recognition model (about 456 MB) is downloaded along with it: the model runs on your own computer, no internet required.
Two Claude Code extensions - superpowers and frontend-design from the official Anthropic catalog.
Development environments
IntelliJ IDEA - the main environment of the course. It comes with three plugins: Python support, the JavaRush plugin (submitting tasks) and the Claude Code plugin (the agent panel right inside the IDE).
Visual Studio Code - the second environment, installed alongside as an option. With two plugins from the same set: JavaRush (beta) and the official Claude Code.
Languages and utilities
- Node.js 24 - the course projects and the result checks run on it.
- Python 3.14 - for scripts and some of the tasks.
- Java 25 (Eclipse Temurin) - the base of the JavaRush platform.
- Gradle 9.5.1 - building Java projects.
- Git - keeping the history of your project; you'll need it later in the course. On Windows, Git Bash is installed together with it.
Settings and sign-in
A settings file for access to the course AI server, the configuration of the JavaRush plugins and the course profile for Claude Code: the agent's working rules, supporting techniques and starter setups for games and web projects. All of it is filled in for you already, so there are no keys to type and nothing to sign into.
How the systems differ
On macOS, if you don't have Homebrew (the package manager) installed, the installer will add it too: Git, Python and VS Code are installed through it.
On Linux, the Node.js, Python and Microsoft repositories (the last one for VS Code) are added. On Debian, Python 3.14 isn't installed: the installer says so plainly in the report, and you'll have to install it yourself.
3. Where everything lands
The installer doesn't scatter files across your system. Everything sits in predictable places, so if you later want to see what went where, you'll find it without digging around.
Programs
| System | Where |
|---|---|
| Windows | Program Files, C:\Gradle |
| macOS | /Applications, /opt |
| Linux | /opt |
Three directories in your home folder
.claude-javarush - the course profile for Claude Code: settings, the agent's working rules, supporting techniques.
.javarush - sign-in settings for the JavaRush plugins and two launch commands (more on those below).
.javarush-backups - backups of the files the installer changed, plus a log of the changes. The last 10 runs or 30 days are kept.
Separately: Claude Code itself goes into ~/.local/bin, and the speech recognition model goes into the Handy data folder.
What changes in system settings
The PATH variable - so the course commands run from the terminal. On Windows the edit goes into the registry, on macOS into the .zprofile file, on Linux into /etc/profile.d/javarush.sh and .profile.
On macOS and Linux our lines are wrapped in the markers # JAVARUSH START and # JAVARUSH END: you can see them with your own eyes, and a rollback removes exactly those lines without touching your own settings.
The Windows registry - three entries, no more: the path to Gradle, the path to the course commands and the accepted IntelliJ IDEA license agreement.
4. Two commands: claude and claude-native
This is an important detail, and it's worth knowing up front.
The course has its own Claude Code settings: the connection to the course server, the agent's working rules, the course characters. Mixing those with your personal settings isn't an option, so we keep the two apart.
claude - starts Claude Code with the course profile. This is what you work with in class.
claude-native - starts your personal Claude Code, as if we weren't here at all. Your own settings, your own account.
Here is how it works: both commands are small scripts in the .javarush/bin folder that launch the same real Claude Code but point it at different settings folders. I keep both within reach myself: the course one for class, my own for everything else.
The installer does not read, change or delete your personal Claude Code profile. If you had one, it stays exactly as it was.
One practical note: the commands show up in a new terminal window. If you type claude in an already open window right after the install, that window doesn't know about these commands yet, so just open a new one.
5. What we do not do
This is probably the most important section. The installer follows the "do no harm" principle, and here's what follows from that.
We do not delete or overwrite what you already have. If your computer already has a different version of Java, Python, Node or Git, it stays where it is. The course version is installed next to it.
We do not touch version managers. If you work through nvm, pyenv, sdkman or asdf, the installer leaves them alone and warns you in the report that it installed a version alongside. Breaking someone else's pyenv is the last thing we want.
We do not reinstall what is already at the right version. A repeat run won't break what's installed: the installer checks each tool and skips whatever is ready.
We do not touch an IntelliJ IDEA that is not ours. If your IDEA came from JetBrains Toolbox, we leave it alone: we install a separate one for the course and tell you about it.
We do not overwrite your consents. If you've already accepted the IDEA license or configured usage statistics, those settings stay yours.
We do not get into startup items, services or system policies. The installer doesn't add itself to startup, doesn't create services or scheduled tasks, doesn't install certificates, and doesn't touch the firewall, hosts or DNS.
We do not widen the AI agent's permissions. The course profile lifts none of Claude Code's restrictions: the agent runs with the usual security settings and asks for permission exactly as it always does.
6. What data is collected
Your personal key
When you download the archive, a personal access key tied to your account is written into it. The JavaRush and Claude Code plugins use that key to sign in on their own, which is why you never have to type any keys yourself. It doesn't reach the log: the same filter that hides passwords hides it too. And it's the reason the archive isn't something to pass on to other people.
The install log
During the install, a detailed log is kept: which steps ran, what was already on the computer, what worked and what didn't. This log stays on your disk. It isn't sent anywhere.
If something goes wrong, you send it yourself, and only if you choose to. On Windows it sits in the temp folder (%TEMP%\javarush-install.log), on macOS and Linux next to the installer itself, in a file called install.log.
Passwords and keys never reach the log: before a line is written, it goes through a filter that replaces tokens and passwords with the marker [SECRET]. The contents of your settings files aren't written there either, only the names of the parameters.
If automatic error reporting ever does appear, we'll say so in advance and leave you a way to switch it off.
The course session log
This one needs to be said plainly.
The course profile for Claude Code is set up to keep a work log. When you solve a course task, a .javarush/cc-transcript.txt file is created in the project folder, and a record of the work goes into it: your requests to the agent, the first lines of its answers, which files it changed, which commands it ran.
Why this is needed: the platform uses this log to check your solution. It's your "show your work" notebook: it shows not just the answer, but how you got there. Sounds unnerving, I know. It's just that without the log the platform only sees what came out at the end.
What matters here:
- the log sits in your project folder, and you can open it and read it;
- it is not sent anywhere on its own - the files that keep the log make no network calls at all;
- passwords and keys in it are masked the same way as in the install log;
- it's kept only in the course profile. Run
claude-nativeand nothing is logged.
Which server the AI work goes through
Another fact that's more useful said out loud than left out.
JavaRush pays for AI access in the course, and it works through our server: llm.javarush.com. That means requests to the model and its answers physically pass through JavaRush infrastructure.
That's what makes free access for students possible. If you want to work directly with your own personal account, that's exactly what the claude-native command is for.
7. How to check and how to undo
You don't have to take this article's word for anything. The installer has modes that let you look first and roll back afterward.
Look without installing anything
The --dry-run flag (-DryRun on Windows) runs the installer in "show only" mode. It prints the full list of what it would do: which files it would download, where it would put them, what it would write into PATH, and then exits without installing anything.
An honest caveat: this mode isn't entirely "hands-off". It overwrites the log file from the previous run, creates service folders and clears out stale backups. No program is installed in the process, and neither your settings nor PATH change.
Leave PATH alone
The --minimal flag (-Minimal on Windows) installs all the programs but writes no paths into system settings: instead it prints the lines for you to add yourself. It's a mode for people who have tuned their environment to their own taste (not sure whether you need it? then you don't).
On Windows this mode is currently incomplete: the path to the course commands does still get added to the user PATH. The edit is reversible, but for now the flag doesn't quite do what it promises. We know, and we'll fix it.
Undo the changes
The --rollback flag (-Rollback on Windows) restores the settings the installer changed: PATH, shell profile files, configurations, registry entries. Every change is written into an operations log, and the rollback follows it strictly.
An extra safeguard: if you edited a file after the install, the rollback will not touch it. It tells you so and shows you where the backup is.
What the rollback does not do: it does not uninstall the programs. IntelliJ IDEA, Java, Node and the rest stay where they are. Instead, the installer prints a list of them with ready-made uninstall commands, and you decide what to remove.
One more honest detail: on Windows, the Java, Node and Python installers write their own paths themselves, bypassing our operations log. The rollback can't undo those entries.
On Windows, the installer prints the ready-made rollback command at the end of the install. Here's how to run it:
- Open PowerShell as administrator: right-click the PowerShell icon, then "Run as administrator".
- Go to the installer folder.
- Run the command:
powershell -NoProfile -ExecutionPolicy Bypass -File .\resources\Windows_install.ps1 -RollbackSee what was done
When it finishes, the installer prints a report listing every step with its status: done, skipped, warning, error or "do it manually". Failures aren't hidden: if something didn't install, it says so directly and gives the reason.
Everything the installer couldn't do on its own is gathered into a separate "Finish manually" block with the exact commands.
8. What you will have to do by hand
Some things can't be automated at all.
Permissions for Handy. On first launch the system will ask for microphone access (on macOS, for Accessibility as well). Without that, voice input won't work. Only a person can grant a permission: no program will do it for you.
The IntelliJ IDEA dialogs that may appear on first start. The installer accepts the license in advance, but if a dialog shows up anyway, accept it.
9. Common questions
How long does the install take?
20-40 minutes, with about a gigabyte downloaded. Most of the time goes on IntelliJ IDEA and the speech recognition model.
Why does it need administrator rights?
The programs go into system folders (Program Files, /opt, /Applications), and without administrator rights nothing can be written there. The settings and the profile, meanwhile, go into your user folder and stay yours.
Can I run the installer twice?
You can. Nothing will break. Anything already installed is skipped. There's a guard against an accidental double launch: the second copy sees that an install is already running and simply closes.
What happens to my Claude Code settings?
Nothing. The course profile lives in a separate folder, and your personal one is neither read nor changed. For your own work there's the claude-native command.
The system shows a warning when I launch it. Is that normal?
Yes. That's how operating systems greet any program downloaded from the internet, and our installer doesn't have a signing certificate yet. On Windows, click "More info", then "Run anyway". On macOS, if the system says it "cannot verify the developer", right-click the file, choose "Open", and confirm once more.
The installer removes the "downloaded from the internet" mark from files. Why?
Otherwise the system blocks the nested files from running and the install breaks off halfway. On Windows this is done for the unpacked folder, on macOS it's the Gatekeeper quarantine cleared from that same folder. The mark is removed only from the installer's own files, and the installer doesn't touch the rest of your files.
Why should I not pass the archive on to anyone?
Your personal sign-in data is inside it. Whoever gets the archive can work under your account. Sharing the download link is fine: everyone gets an archive of their own.
Something went wrong. What do I do?
Look at the report at the end and at the install.log file: they show which step failed and why. If it isn't clear, send that file to support. That's the normal route, not a last resort.
10. If you would rather not install everything at once
The installer isn't a required step of the course; it's a way to save time. Everything it does is walked through step by step in the lectures: Claude Code installs with one command, the settings are copied as one file.
You connect the rest of the tools as you need them, and by the time you do, you'll understand what each one is for. They stick better that way than as a list of ten lines.