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src/apt/NOTES.md

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+# OS Support
+
+This feature supports recent versions of Debian and Ubuntu distributions with the `apt` package manager. It works with any base image using these distributions, like `ubuntu:focal` or `debian:buster`.
+
+`bash` is required to execute the `install.sh` script.

src/apt/README.md

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+# Aptfile Dependencies (apt)
+
+Install apt dependencies defined in an `Aptfile.dev` file. This feature is inspired by the approach found in [heroku-buildpack-apt](https://github.com/heroku/heroku-buildpack-apt) and [Aptfile Buildpack on App Platform](https://docs.digitalocean.com/products/app-platform/reference/buildpacks/aptfile/). It simplifies the process of managing and installing apt packages required for a development environment by specifying them in one file.
+
+## Example Usage
+
+```json
+"features": {
+  "ghcr.io/viktorianer/features/apt:1": {
+    "devFile": "../Aptfile.dev"
+  }
+}
+```
+
+## Options
+
+| Options Id | Description | Type   | Default Value |
+|------------|-------------|--------|---------------|
+| devFile    | Path to the Aptfile.dev file. This is where the list of apt packages is defined. | string | `../Aptfile.dev` |
+
+## How It Works
+
+- The feature reads the list of packages from the `Aptfile.dev` file and installs them during the container setup.
+- The default path is `Aptfile.dev`, but this can be customized using the `devFile` option.
+- It removes any commented or empty lines before installing the packages with `apt-get install`.
+
+Example `Aptfile.dev`:
+
+```bash
+# Video thumbnails
+ffmpeg
+libvips
+
+# PDF thumbnails
+poppler-utils
+# mupdf
+# mupdf-tools
+
+# PostgreSQL
+libpq-dev
+postgresql-client
+```