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README.md

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+# cdd
+
+A TUI that lets you jump to recent Projects.
+
+## Demo
+
+<!-- Maintainer: record a terminal-session GIF or asciinema cast of the
+     Picker in action and drop it here. No recording tool is available in
+     this environment. -->
+
+## Install
+
+### GitHub Releases
+
+Download a prebuilt binary from the [Releases](https://github.com/kryft-dev/cdd/releases)
+page. Archives are published as `tar.gz` for `linux` and `darwin`, each in
+`amd64` and `arm64`. Verify a download against the release's
+`checksums.txt`:
+
+```sh
+sha256sum --check --ignore-missing checksums.txt
+```
+
+Then extract the archive and put the `cdd` binary on your `PATH`.
+
+### go install
+
+```sh
+go install github.com/kryft-dev/cdd/cmd/cdd@latest
+```
+
+## Shell setup
+
+`cdd` needs a shell Wrapper so choosing a Project in the Picker can actually
+Jump your shell there — a subprocess cannot change its parent shell's
+working directory on its own.
+
+**fish** — add to `~/.config/fish/config.fish`:
+
+```fish
+cdd init fish | source
+```
+
+**bash** — add to `~/.bashrc`:
+
+```sh
+eval "$(cdd init bash)"
+```
+
+**zsh** — add to `~/.zshrc`:
+
+```sh
+eval "$(cdd init zsh)"
+```
+
+## First run
+
+Create a `config.toml` (see [Config reference](#config-reference)) with at
+least a `root`, then seed History with a Scan of everything already under
+Root:
+
+```sh
+cdd scan
+```
+
+## Usage
+
+```sh
+cdd            # open the Picker over History, ordered by recency
+cdd <query>    # open the Picker pre-filtered by query
+```
+
+### Keys
+
+Default key map:
+
+| Key | Action |
+| --- | --- |
+| type | filter the list |
+| `↑` / `ctrl+p` | move up |
+| `↓` / `ctrl+n` | move down |
+| `enter` | Jump to the selected Project |
+| `esc` / `ctrl+c` | cancel |
+| `ctrl+u` | clear the filter |
+
+Vim key map (`keys.vim = true`): the list is focused on open.
+
+| Key | Action |
+| --- | --- |
+| `j` | move down |
+| `k` | move up |
+| `g` / `G` | jump to first / last row |
+| `f` / `/` | focus the filter |
+| `esc` (filter) | return to the list, keeping the query |
+| `esc` / `q` | cancel |
+| `enter` | Jump to the selected Project |
+
+## Config reference
+
+`cdd` reads `config.toml` from `$XDG_CONFIG_HOME/cdd/config.toml`, falling
+back to `~/.config/cdd/config.toml` when `XDG_CONFIG_HOME` is unset.
+
+```toml
+root = "~/Developer"      # required, no default
+exclude = []              # paths relative to Root, glob-matched
+include_hidden = false
+[history]
+max_visits = 1000         # must be >= 1
+[keys]
+vim = false
+```
+
+- `root` (required): the top-level directory whose Kinds are searched for
+  Projects. A leading `~` is expanded to the user's home directory;
+  `$VAR` is left as-is.
+- `exclude`: paths relative to Root, matched with `path.Match` semantics,
+  that are skipped when discovering Kinds and Projects.
+- `include_hidden`: when `false` (the default), hidden directories are
+  excluded at both Kind and Project level.
+- `[history].max_visits`: the maximum number of Visits kept in History.
+  Must be at least 1; defaults to `1000`.
+- `[keys].vim`: when `true`, the Picker opens with the list focused and
+  uses the vim key map described above. Defaults to `false`, the default
+  key map.
+
+History is stored at `$XDG_DATA_HOME/cdd/history`, falling back to
+`~/.local/share/cdd/history` when `XDG_DATA_HOME` is unset.
+
+## How it works
+
+A Scan sweeps Root once and seeds History with a Visit per discovered
+Project, dated from evidence found inside the Project itself. The Picker
+lists Projects drawn from History, most recently visited first, and lets
+you choose one; choosing a Project records a new Visit and hands its path
+to the Wrapper, which turns it into a Jump in your shell.
+
+## Contributing
+
+See [CONTRIBUTING.md](CONTRIBUTING.md) for development setup, the
+[CONTEXT.md](CONTEXT.md) glossary, and the commit and pull request
+workflow.
+
+## License
+
+[MIT](LICENSE)