feat(herdr): declarative config with tmux prefix and repo/nav keymaps

- ctrl+s prefix to match tmux
- prefix+f: fzf ~/ghq repos into a workspace (twm replacement)
- prefix+shift+f: prompt for ghq get, clone, and open
- prefix+g: lazygit in the current repo
- prefix+j/k and shift+j/k: navigate spaces/agents

2 files changed, 86 insertions, 0 deletions

diff --git a/modules/home/default.nix b/modules/home/default.nix
index 7f3e820..f82d139 100644
--- a/modules/home/default.nix
+++ b/modules/home/default.nix
@@ -5,6 +5,7 @@
     ./claude.nix
     ./git.nix
     ./ghostty.nix
+    ./herdr.nix
     ./starship.nix
     ./tmux.nix
     ./lazygit.nix
diff --git a/modules/home/herdr.nix b/modules/home/herdr.nix
new file mode 100644
index 0000000..aa14d30
--- /dev/null
+++ b/modules/home/herdr.nix
@@ -0,0 +1,85 @@
+{ pkgs, ... }:
+
+let
+  # twm replacement: fuzzy-pick a repo under ~/ghq and open it as a herdr
+  # workspace, reusing an already-open workspace with the same name.
+  repoPicker = pkgs.writeShellApplication {
+    name = "herdr-repo-picker";
+    runtimeInputs = [ pkgs.ghq pkgs.fzf pkgs.jq pkgs.herdr ];
+    text = ''
+      sel=$(ghq list -p | fzf --prompt 'repo ❯ ' --reverse) || exit 0
+      [ -n "''${sel:-}" ] || exit 0
+
+      label=''${sel##*/}
+      existing=$(herdr workspace list \
+        | jq -r --arg l "$label" '.result.workspaces[] | select(.label == $l) | .workspace_id' \
+        | head -n1)
+
+      if [ -n "$existing" ]; then
+        herdr workspace focus "$existing" >/dev/null
+      else
+        herdr workspace create --cwd "$sel" --label "$label" --focus >/dev/null
+      fi
+    '';
+  };
+
+  # Prompt for a `ghq get` target, clone it, then open the clone as a workspace.
+  repoGet = pkgs.writeShellApplication {
+    name = "herdr-repo-get";
+    runtimeInputs = [ pkgs.ghq pkgs.herdr ];
+    text = ''
+      read -r -p 'ghq get ❯ ' q || exit 0
+      [ -n "''${q:-}" ] || exit 0
+
+      before=$(ghq list -p | sort)
+      ghq get "$q"
+
+      # Prefer the repo that appeared; fall back to matching the query.
+      dir=$(comm -13 <(printf '%s\n' "$before") <(ghq list -p | sort) | head -n1)
+      [ -n "$dir" ] || dir=$(ghq list -p "$q" | head -n1)
+      [ -n "$dir" ] || exit 0
+
+      label=''${dir##*/}
+      herdr workspace create --cwd "$dir" --label "$label" --focus >/dev/null
+    '';
+  };
+in
+{
+  home.packages = [ repoPicker repoGet ];
+
+  home.file.".config/herdr/config.toml".text = ''
+    [keys]
+    # Match the tmux prefix (see modules/home/tmux.nix).
+    prefix = "ctrl+s"
+
+    # Vim-style movement through the sidebar: j/k for spaces, shift+j/k for agents.
+    next_workspace = "prefix+j"
+    previous_workspace = "prefix+k"
+    next_agent = "prefix+shift+j"
+    previous_agent = "prefix+shift+k"
+
+    # prefix+f: fuzzy-pick a ~/ghq repo and open it as a workspace (replaces `twm`).
+    [[keys.command]]
+    key = "prefix+f"
+    type = "popup"
+    command = "${repoPicker}/bin/herdr-repo-picker"
+    width = "70%"
+    height = "60%"
+
+    # prefix+shift+f: prompt for `ghq get <input>`, clone it, and open it.
+    [[keys.command]]
+    key = "prefix+shift+f"
+    type = "popup"
+    command = "${repoGet}/bin/herdr-repo-get"
+    width = "70%"
+    height = "40%"
+
+    # prefix+g: lazygit in the current pane's repo (replaces tmux `bind g`).
+    [[keys.command]]
+    key = "prefix+g"
+    type = "popup"
+    command = "${pkgs.lazygit}/bin/lazygit -p \"$HERDR_ACTIVE_PANE_CWD\""
+    width = "90%"
+    height = "90%"
+  '';
+}