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docs/guides/homebrew-install.md

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+# Installing RegShape with Homebrew
+
+RegShape is distributed through a [Homebrew](https://brew.sh) tap so you can
+install and update the CLI with a single command on macOS and Linux.
+
+## Install
+
+```bash
+brew install toddysm/regshape/regshape
+```
+
+This automatically taps `toddysm/regshape` and installs the `regshape` formula.
+You can also tap explicitly first:
+
+```bash
+brew tap toddysm/regshape
+brew install regshape
+```
+
+Verify the installation:
+
+```bash
+regshape --version
+regshape --help
+```
+
+## Upgrade
+
+```bash
+brew update
+brew upgrade regshape
+```
+
+## Uninstall
+
+```bash
+brew uninstall regshape
+brew untap toddysm/regshape
+```
+
+## How it works
+
+- The formula lives in the [toddysm/homebrew-regshape](https://github.com/toddysm/homebrew-regshape)
+  tap repository.
+- RegShape is installed into an isolated Python virtualenv with pinned
+  dependency resources, so it does not interfere with your system Python.
+- On every RegShape release, the project's release workflow publishes the new
+  version to PyPI and then opens a pull request in the tap to bump the formula
+  (source URL and checksum) to match. Once that PR is merged, `brew upgrade`
+  picks up the new version.
+
+## Troubleshooting
+
+- **`Error: No available formula`** — run `brew update` and ensure the tap is
+  present with `brew tap`.
+- **Stale version after a release** — the formula bump PR in the tap may not be
+  merged yet; check the [tap pull requests](https://github.com/toddysm/homebrew-regshape/pulls).