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README.md

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+# Fast `cargo install` action
+
+This GitHub Action installs a Rust crate using precompiled signed binaries built
+on GitHub and hosted as GitHub release artifacts.
+
+## Example workflow
+
+```yaml
+name: test suite
+on: [push, pull_request]
+
+jobs:
+  expand:
+    name: cargo expand
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: dtolnay/install@master
+        with:
+          crate: cargo-expand
+      - run: cargo expand --help
+```
+
+## Inputs
+
+| Name    | Required | Description                                  |
+| ------- | :------: | -------------------------------------------- |
+| `crate` | ✓        | Name of crate as published to crates.io      |
+| `bin`   |          | Name of binary; default = same as crate name |
+
+## Security considerations
+
+Check the `.github/workflows` directory of this repo for the GitHub Actions
+logic which compiles, signs, and publishes each binary.
+
+This Action downloads both the binary executable and its signature. The
+signature is verified using gpg and the public key available in
+`signing-key.asc`. The corresponding private key is provided to this repo's
+build jobs as a GitHub secret.
+
+## License
+
+The scripts and documentation in this project are released under the [MIT
+License].
+
+[MIT License]: LICENSE