# shepherd-launcher

A child-friendly, parent-guided desktop environment *alternative* for Wayland,
allowing supervised access to applications and content that you define.

Its primary goal is to return control of child-focused computing to parents,
not software or hardware vendors, by providing:

* the ease-of-use of game consoles
* access to any application that can be run, emulated, or virtualized in desktop Linux
* with granular access controls inspired by and exceeding those in iOS Screen Time

While this repository provides some examples for existing software packages
(including non-free software and abandonware), `shepherd-launcher` is
*non-prescriptive*: as the end user, you are free to use them, not use them,
or write your own.

## Screenshots

### Home screen

`shepherd-launcher` presents a list of activities for the user to pick from.

![Home screen at 3:00 PM showing the following set of activities: Tux Math, Putt Putt Joins the Circus, Secret of Monkey Island, GCompris, Minecraft, Celeste, A Short Hike, Big Buck Bunny, and Lofi Beats.](./docs/readme/home-normal.png)

The flow of manually opening and closing activities should be familiar.

<video controls src="https://git.armeafamily.com/albert/shepherd-launcher/raw/branch/main/docs/readme/basic-flow.webm" alt="Happy path demo showing home screen --> GCompris --> home screen"></video>

Activities can be made selectively available at certain times of day.

![Home screen at 9:00 PM showing Lofi Beats as the only available activity.](./docs/readme/home-bedtime.png)

This example, shown at 9 PM, has limited activities as a result.

### Time limits

Activities can have configurable time limits, including:
* individual session length
* total usage per day
* cooldown periods before that particular activity can be restarted

<video controls src="https://git.armeafamily.com/albert/shepherd-launcher/raw/branch/main/docs/readme/tuxmath-expiring.webm" alt="TuxMath session shown about to expire, including warnings and automatic termination"></video>

### Anything on Linux

If it can run on Linux in *any way, shape, or form*, it can be supervised by
`shepherd-launcher`.

!["Big Buck Bunny" hosted within shepherd-launcher UI](./docs/readme/apps-media.jpg)

> [Big Buck Bunny](https://peach.blender.org/) playing locally via `mpv`

!["Putt Putt Joins the Circus" hosted within shepherd-launcher UI](./docs/readme/apps-puttputt.png)

> [Putt Putt Joins the Circus](https://humongous.fandom.com/wiki/Putt-Putt_Joins_the_Circus)
> running via [ScummVM](https://www.scummvm.org/)

!["The Secret of Monkey Island" hosted within shepherd-launcher UI](./docs/readme/apps-monkey.png)

> [The Secret of Monkey Island](https://en.wikipedia.org/wiki/The_Secret_of_Monkey_Island)
> running via [ScummVM](https://www.scummvm.org/)

![Minecraft hosted within shepherd-launcher UI](./docs/readme/apps-minecraft.jpg)

> [Minecraft](https://www.minecraft.net/) running via the
> [Prism Launcher Flatpak](https://flathub.org/en/apps/org.prismlauncher.PrismLauncher)

![Celeste hosted within shepherd-launcher UI](./docs/readme/apps-celeste.png)

> [Celeste](https://www.celestegame.com/) running via Steam

![A Short Hike hosted within shepherd-launcher UI](./docs/readme/apps-ashorthike.png)

> [A Short Hike](https://ashorthike.com/) running via Steam

## Core concepts

* **Launcher-first**: only one foreground activity at a time
* **Time-scoped execution**: applications are granted time slices, not unlimited sessions
* **Parent-defined policy**: rules live outside the application being run
* **Wrappers, not patches**: existing software is sandboxed, not modified
* **Revocable access**: sessions end predictably and enforceably

## Non-goals

1. Modifying or patching third-party applications
2. Circumventing DRM or platform protections
3. Replacing parental involvement with automation or third-party content moderation
4. Remotely monitoring users with telemetry
5. Collecting, storing, or reporting personally identifying information (PII)

### Regarding age verification

`shepherd-launcher` may be considered "operating system software" under the
[Digital Age Assurance Act][age-california] and similar legislation,
and therefore subject to an age verification requirement.

[age-california]: https://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=202520260AB1043

As legislated, such requirements are fundamentally incompatible with non-goals 3, 4, and 5.

`shepherd-launcher` will *never* collect telemetry or PII, and as such, it will never implement this type of age verification.

As a result, `shepherd-launcher` is not licensed for use in any region that requires OS-level age verification by law.
**If you reside in any such region, you may not download, install, or redistribute `shepherd-launcher`.**

This includes, but is not limited to:

* California
* Louisiana
* Texas
* Utah

[Many other states are considering similar legislation.](https://actonline.org/2025/01/14/the-abcs-of-age-verification-in-the-united-states/)

If you disagree with this assessment and you reside in an affected region, **please contact your representatives.**

## Installation

`shepherd-launcher` is pre-alpha and in active development. The helper at
`./scripts/shepherd` can be used to build and install a *fully functional*
local kiosk setup from source:

Check out this repository and run `./scripts/shepherd --help` or see
[INSTALL.md](./docs/INSTALL.md) for more.

## Example configuration

All behavior shown above is driven entirely by declarative configuration.

For the Minecraft example shown above:

```toml
# Prism Launcher - Minecraft launcher (Flatpak)
# Install: flatpak install flathub org.prismlauncher.PrismLauncher
[[entries]]
id = "prism-launcher"
label = "Prism Launcher"
icon = "org.prismlauncher.PrismLauncher"

[entries.kind]
type = "flatpak"
app_id = "org.prismlauncher.PrismLauncher"

[entries.availability]
[[entries.availability.windows]]
days = "weekdays"
start = "15:00"
end = "18:00"

[[entries.availability.windows]]
days = "weekends"
start = "10:00"
end = "20:00"

[entries.limits]
max_run_seconds = 1800  # 30 minutes (roughly 3 in-game days)
daily_quota_seconds = 3600  # 1 hour per day
cooldown_seconds = 600  # 10 minute cooldown

[[entries.warnings]]
seconds_before = 120
severity = "warn"
message = "2 minutes remaining - save your game!"

[[entries.warnings]]
seconds_before = 30
severity = "critical"
message = "30 seconds! Save NOW!"
```

See [config.example.toml](./config.example.toml) and 
[the Wiki](https://git.armeafamily.com/albert/shepherd-launcher/wiki)
for more.

## Development

Build instructions and contribution guidelines are described in
[CONTRIBUTING.md](./CONTRIBUTING.md).

If you'd like to help out, you can find potential work items on
[the Issues page](https://git.armeafamily.com/albert/shepherd-launcher/issues).
You may email me patch sets at <shepherd-launcher-patch@albertarmea.com>.

## Written in 2025, responsibly

This project stands on the shoulders of giants in systems software and
compatibility infrastructure:

* Wayland and Sway
* Rust
* Flatpak and Snap
* Proton and WINE

This project was written with the assistance of generative AI-based coding
agents. Substantial prompts and design docs provided to agents are disclosed in
[docs/ai](./docs/ai/).
