Offline Hedy

We also provide Hedy as an application which can be run locally. This might be a nice alternative to our online service in case of poor internet connectivity in the classroom, or if you or your school has privacy concerns around having students use online tools.

Offline Hedy is currently available for:

• Windows x64
• MacOS Intel and Silicon
• Ubuntu x64 and arm64

There are two ways you can use Offline Hedy: you can either download the application on the laptops of every student (individual hosts) or you can use one machine to host the application and let each student connect to the host machine via a (local) network (single host).

If you simply want your students to have access to and be able to work on the problems, it is recommended to use this first mode where you download Offline Hedy on every laptop. This is slightly more tedious to set up as you have to download it on every computer, but will be easier during 'everyday use'. This does come with the downside that you, the teacher, cannot check the work of your students. (This mode is also recommended for use in outreach-like events where access to the problems is more important than checking the code and determining a grade.)

The single host mode might be preferred if you want to enjoy the full capabilities our online service offers or if the operating system of the student machines is not supported. In this mode the host computer acts as the server on which the website is hosted. So, your students can easily connect to Offline Hedy using only their browser and you will be able to use it as you would our online service. You can create classes, alter which exercises are shown to your students, and check the submitted code. However, to do this you must still have a (local) network set up to which all laptops are connected.

In the following steps How to download and Installing and launching Offline Hedy, we shall provide instructions on how to install Offline Hedy on a single machine. This has to be repeated for every machine on which you want to set up Offline Hedy. How to use Offline Hedy in these two different modes will be explained in Using Offline Hedy.

How to download

To download Offline Hedy, visit our Releases page, click on the latest release, and scroll down to find a series of zip files under 'Assets' (e.g. offlinehedy-x.y.z-macos-intel.zip). The names of these zip files are structured in the following way: offlinehedy-[Release Name]-[Operating System]-[Architecture].zip. Please choose the file which fits your operating system.

• offlinehedy-x.y.z-windows-x64.zip should work for most Windows systems.
• To find whether you need the Intel or Silicon build as a MacOS user, please take a look at which processor/chip your system has by going to About This Mac found in the dropdown menu from the Apple logo in the top-left corner. If the chip is made by Intel please choose the Intel build, otherwise (if the chip is an M-series processor, like Apple M4) please choose the Silicon build.
• For Ubuntu users the architecture can be found using uname -m. Please note that x86_64 needs the x64 build.

If your operating system and/or architecture is not supported please let us know!

Installing and launching Offline Hedy

In the following section the installation instructions shall be split up for each operating system:

• Windows
• MacOS
• Ubuntu

Installing on Windows

1. Unpack the downloaded zip-file in the desired location by right-clicking the file, selecting 'Extract All...', and selecting the correct folder.
2. Open the extracted folder and launch the Hedy executable.

3. (On first launch) you will probably get a security warning from Microsoft Defender SmartScreen warning you about the unrecognised app.

4. Press More info and click Run anyway.

5. This shall then open a Command Prompt window, which, in turn, will open a browser window.
6. You will most likely also get a notification from Windows Firewall asking whether or not you want Hedy to be able to access the local network. It is necessary to allow this if you want to use the aforementioned single host setup. For the individual hosts, it does not matter if you allow this or not.
7. If everything worked correctly you should now see the Hedy homepage. If no browser window was opened you can either ctrl+click one of the hyperlinks in the Command Prompt or go to http://localhost/ in your browser manually.

Installing on MacOS

1. Unpack the downloaded zip-file and move it to the desired location.
2. Open the extracted folder and launch the Hedy executable.

3. (On first launch) you will probably get an error that "hedy" could not be opened. Please press 'Done' ($${\color{red}not}$$ 'Move to Trash').

4. Open the System settings of your Mac and go to Privacy and Security. Scroll down to Security where you will see a notification "hedy" was blocked to protect your mac. Press 'Open Anyway'.

5. You will get a pop-up reminding that Apple could not verify that the software is free from malware. Press 'Open Anyway' once more.

6. This will be followed by another pop up where you can use touch-id or the password of the system to verify you want to open Hedy.

7. This will finally open a Terminal window which launches Hedy, which is probably followed by a pop-up asking for access to the folder in which hedy is located. Please allow this.

8. If everything went well, this should now open a browser window which shows the Hedy homepage. If no browser window was opened you can either command+click one of the hyperlinks in the Command Prompt or go to http://localhost/ in your browser manually.

Installing on Ubuntu

1. Unpack the downloaded zip-file in the desired location using e.g. unzip file.zip -d destination_folder.
2. Go to the extracted folder and launch the Hedy executable with sudo rights using sudo ./hedy.
3. This shall open a browser window if possible which shows the Hedy homepage. If no browser window was opened you can either ctrl+click one of the hyperlinks in the Command Prompt or go to http://localhost/ in your browser manually.

Using Offline Hedy

Individual hosts

If every student machine has a copy of Offline Hedy installed, launching Hedy, going to http://localhost/ in their browser (which should happen automatically) and pressing Let's get started! on the homepage is enough to get started with Hedy! If the browser is accidentally closed, reopening the browser and going back to http://localhost/ should reopen Hedy. To fully close Hedy please use ctrl+C in the command prompt/terminal and close the terminal window if this did not happen automatically.

Usage at outreach-like events.

At outreach-like events if you connect to Offline Hedy using a private browser window, you can reset progress made on the computer by simply closing the private window and reopening it (the terminal/command prompt can keep running and does not need to be relaunched). User progress is stored in the cookies, so reopening the private window should forget any progress made.

Single host

When launching Offline Hedy, the terminal will list some websites from which you will be able to access the hosted service.

http://localhost/ will only work on this machine, but the other links should be accessible from other computers on your local network. Make sure the student laptops and the host machine are on the same network, your students will then be able to connect to the hosted Offline Hedy just as they would be able to connect to the online service. Please keep in mind that the address might change each time you re-launch Offline Hedy.

Setting up a teacher account

Since the host computer is simply replacing our servers, you still need to follow all the steps of setting up a teacher account, creating student accounts for your class and distributing them among your students, just as you would on online Hedy.

You can set up a teacher account by going to http://localhost/invite/newteacher and selecting 'Create account'.

Then, select 'Teacher' and continue the sign-up process.

You can also use the built-in teacher account we have, with username teacher1 and password 123456.

Upgrading to a newer version

All data concerning the teachers, the students, and their submissions is stored in the database.json file which is located in the same folder as the executable.

If you wish to upgrade Offline Hedy to a newer version, you can simply download the newest version from our Releases page and follow this guide once again to properly install it. Finally, to transfer the data between versions, you should replace the database.json file in the folder containing the new version with the database.json from the folder containing the version you were previously using. After launching the new version, double-check if all data is still there by logging into your account. If this is not the case please try again!

If you wish to reset all data (for example when a new school year has begun), simply download Offline Hedy once again from our Releases page.