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+# `AddPackage`
+
+<!-- TOC -->
+- [Identification/Fetching](#identificationfetching)
+- [Hashing](#hashing)
+- [Other Options](#other-options)
+- [Extra Variables](#extra-variables)
+- [System/Bundled Packages](#systembundled-packages)
+- [Identification](#identification)
+<!-- /TOC -->
+
+## Identification/Fetching
+
+- `NAME` (required): The package name (must be the same as the `find_package` name if applicable)
+- `VERSION`: The minimum version of this package that can be used on the system
+- `GIT_VERSION`: The "version" found within git
+- `URL`: The URL to fetch.
+- `REPO`: The repo to use (`owner/repo`).
+- `GIT_HOST`: The Git host to use
+  * Defaults to `github.com`. Do not include the protocol, as HTTPS is enforced.
+- `TAG`: The tag to fetch, if applicable.
+- `ARTIFACT`: The name of the artifact, if applicable.
+- `SHA`: Commit sha to fetch, if applicable.
+- `BRANCH`: Branch to fetch, if applicable.
+
+The following configurations are supported, in descending order of precedence:
+
+- `URL`: Bare URL download, useful for custom artifacts
+  * If this is set, `GIT_URL` or `REPO` should be set to allow the dependency viewer to link to the project's Git repository.
+  * If this is NOT set, `REPO` must be defined.
+- `REPO + TAG + ARTIFACT`: GitHub release artifact
+  * The final download URL will be `https://github.com/${REPO}/releases/download/${TAG}/${ARTIFACT}`
+  * Useful for prebuilt libraries and prefetched archives
+- `REPO + TAG`: GitHub tag archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/tags/${TAG}.tar.gz`
+  * Useful for pinning to a specific tag, better for build identification
+- `REPO + SHA`: GitHub commit archive
+  * The final download URL will be `https://github.com/${REPO}/archive/${SHA}.zip`
+  * Useful for pinning to a specific commit
+- `REPO + BRANCH`: GitHub branch archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/heads/${BRANCH}.zip`
+  * Generally not recommended unless the branch is frozen
+- `REPO`: GitHub master archive
+  * The final download URL will be `https://github.com/${REPO}/archive/refs/heads/master.zip`
+  * Generally not recommended unless the project is dead
+
+## Hashing
+
+Hashing is used for verifying downloads. It's highly recommended to use these.
+
+- `HASH_ALGO` (default `SHA512`): Hash algorithm to use
+
+Hashing strategies, descending order of precedence:
+
+- `HASH`: Bare hash verification, useful for static downloads e.g. commit archives
+- `HASH_SUFFIX`: Download the hash as `${DOWNLOAD_URL}.${HASH_SUFFIX}`
+  * The downloaded hash *must* match the hash algorithm and contain nothing but the hash; no filenames or extra content.
+- `HASH_URL`: Download the hash from a separate URL
+
+## Other Options
+
+- `KEY`: Custom cache key to use (stored as `.cache/cpm/${packagename_lower}/${key}`)
+  * Default is based on, in descending order of precedence:
+    - First 4 characters of the sha
+    - `GIT_VERSION`
+    - Tag
+    - `VERSION`
+    - Otherwise, CPM defaults will be used. This is not recommended as it doesn't produce reproducible caches
+- `DOWNLOAD_ONLY`: Whether or not to configure the downloaded package via CMake
+  * Useful to turn `OFF` if the project doesn't use CMake
+- `SOURCE_SUBDIR`: Subdirectory of the project containing a CMakeLists.txt file
+- `FIND_PACKAGE_ARGUMENTS`: Arguments to pass to the `find_package` call
+- `BUNDLED_PACKAGE`: Set to `ON` to default to the bundled package
+- `FORCE_BUNDLED_PACKAGE`: Set to `ON` to force the usage of the bundled package, regardless of CPMUTIL_FORCE_SYSTEM or `<package>_FORCE_SYSTEM`
+- `OPTIONS`: Options to pass to the configuration of the package
+- `PATCHES`: Patches to apply to the package, stored in `.patch/${packagename_lower}/0001-patch-name.patch` and so on
+- Other arguments can be passed to CPM as well
+
+## Extra Variables
+
+For each added package, users may additionally force usage of the system/bundled package.
+
+- `${package}_FORCE_SYSTEM`: Require the package to be installed on the system
+- `${package}_FORCE_BUNDLED`: Force the package to be fetched and use the bundled version
+
+## System/Bundled Packages
+
+Descending order of precedence:
+- If `${package}_FORCE_SYSTEM` is true, requires the package to be on the system
+- If `${package}_FORCE_BUNDLED` is true, forcefully uses the bundled package
+- If `CPMUTIL_FORCE_SYSTEM` is true, requires the package to be on the system
+- If `CPMUTIL_FORCE_BUNDLED` is true, forcefully uses the bundled package
+- If the `BUNDLED_PACKAGE` argument is true, forcefully uses the bundled package
+- Otherwise, CPM will search for the package first, and if not found, will use the bundled package
+
+## Identification
+
+All dependencies must be identifiable in some way for usage in the dependency viewer. Lists are provided in descending order of precedence.
+
+URLs:
+
+- `GIT_URL`
+- `REPO` as a Git repository
+  * You may optionally specify `GIT_HOST` to use a custom host, e.g. `GIT_HOST git.crueter.xyz`. Note that the git host MUST be GitHub-like in its artifact/archive downloads, e.g. Forgejo
+  * If `GIT_HOST` is unspecified, defaults to `github.com`
+- `URL`
+
+Versions (bundled):
+
+- `SHA`
+- `GIT_VERSION`
+- `VERSION`
+- `TAG`
+- "unknown"
+
+If the package is a system package, AddPackage will attempt to determine the package version and append ` (system)` to the identifier. Otherwise, it will be marked as `unknown (system)`