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+# Modules
+
+Modules as they are used in `modules` exist primarily to check the shape and content of CUDA redistributable and feature manifests. They are ultimately meant to reduce the repetitive nature of repackaging CUDA redistributables.
+
+Building most redistributables follows a pattern of a manifest indicating which packages are available at a location, their versions, and their hashes. To avoid creating builders for each and every derivation, modules serve as a way for us to use a single `genericManifestBuilder` to build all redistributables.
+
+## `generic`
+
+The modules in `generic` are reusable components meant to check the shape and content of NVIDIA's CUDA redistributable manifests, our feature manifests (which are derived from NVIDIA's manifests), or hand-crafted Nix expressions describing available packages. They are used by the `genericManifestBuilder` to build CUDA redistributables.
+
+Generally, each package which relies on manifests or Nix release expressions will create an alias to the relevant generic module. For example, the [module for CUDNN](./cudnn/default.nix) aliases the generic module for release expressions, while the [module for CUDA redistributables](./cuda/default.nix) aliases the generic module for manifests.
+
+Alternatively, additional fields or values may need to be configured to account for the particulars of a package. For example, while the release expressions for [CUDNN](./cudnn/releases.nix) and [TensorRT](./tensorrt/releases.nix) are very close, they differ slightly in the fields they have. The [module for CUDNN](./modules/cudnn/default.nix) is able to use the generic module for release expressions, while the [module for TensorRT](./modules/tensorrt/default.nix) must add additional fields to the generic module.
+
+### `manifests`
+
+The modules in `generic/manifests` define the structure of NVIDIA's CUDA redistributable manifests and our feature manifests.
+
+NVIDIA's redistributable manifests are retrieved from their web server, while the feature manifests are produced by [`cuda-redist-find-features`](https://github.com/connorbaker/cuda-redist-find-features).
+
+### `releases`
+
+The modules in `generic/releases` define the structure of our hand-crafted Nix expressions containing information necessary to download and repackage CUDA redistributables. These expressions are created when NVIDIA-provided manifests are unavailable or otherwise unusable. For example, though CUDNN has manifests, a bug in NVIDIA's CI/CD causes manifests for different versions of CUDA to use the same name, which leads to the manifests overwriting each other.
+
+### `types`
+
+The modules in `generic/types` define reusable types used in both `generic/manifests` and `generic/releases`.