cmux-tui manual-IO data path: pipe-io relay + reconnecting pump (no attach subprocess in the pane)

Packages/macOS/CmuxSettings/Sources/CmuxSettings/Keys/BetaFeaturesCatalogSection.swift

@@ -102,6 +102,19 @@ public struct BetaFeaturesCatalogSection: SettingCatalogSection {
         userDefaultsKey: "terminal.beta.tuiBackend.enabled"
     )
 
+    /// Manual-IO variant of the cmux-tui terminal backend: instead of
+    /// running `cmux-tui attach` as the surface command (exec bridge), the
+    /// surface runs in Ghostty's manual-mirror IO mode and an app-side pump
+    /// relays bytes to/from the daemon through `attach --pipe-io`. The
+    /// surface parses the daemon terminal's own byte stream, so input
+    /// encodings always match the daemon's mode state. Requires
+    /// `tuiTerminalBackend`; defaults off (exec bridge).
+    public let tuiTerminalBackendManualIO = DefaultsKey<Bool>(
+        id: "terminal.beta.tuiBackend.manualIO",
+        defaultValue: false,
+        userDefaultsKey: "terminal.beta.tuiBackend.manualIO"
+    )
+
     /// Path to the cmux-tui binary used by the `tuiTerminalBackend` spike.
     /// Dev-only setting with a spike-only default pointing at a locally
     /// installed npm binary; there is no bundled artifact yet (that is build

Packages/macOS/CmuxSettingsUI/Sources/CmuxSettingsUI/Sections/BetaFeaturesSection.swift

@@ -14,6 +14,7 @@ public struct BetaFeaturesSection: View {
     @State private var customSidebars: DefaultsValueModel<Bool>
     @State private var remoteTmux: DefaultsValueModel<Bool>
     @State private var tuiTerminalBackend: DefaultsValueModel<Bool>
+    @State private var tuiTerminalBackendManualIO: DefaultsValueModel<Bool>
     @State private var workspaceTodoControls: DefaultsValueModel<Bool>
     @State private var workspaceTodosChecklistStyle: DefaultsValueModel<WorkspaceTodoChecklistStyle>
 
@@ -25,6 +26,7 @@ public struct BetaFeaturesSection: View {
         _customSidebars = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.customSidebars))
         _remoteTmux = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.remoteTmux))
         _tuiTerminalBackend = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.tuiTerminalBackend))
+        _tuiTerminalBackendManualIO = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.tuiTerminalBackendManualIO))
         _workspaceTodoControls = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.workspaceTodoControls))
         _workspaceTodosChecklistStyle = State(initialValue: DefaultsValueModel(store: defaultsStore, key: catalog.betaFeatures.workspaceTodosChecklistStyle))
     }
@@ -51,6 +53,8 @@ public struct BetaFeaturesSection: View {
                 SettingsCardDivider()
                 tuiTerminalBackendRow
                 SettingsCardDivider()
+                tuiTerminalBackendManualIORow
+                SettingsCardDivider()
                 workspaceTodoControlsRow
                 SettingsCardDivider()
                 workspaceTodosChecklistStyleRow
@@ -68,6 +72,7 @@ public struct BetaFeaturesSection: View {
             customSidebars,
             remoteTmux,
             tuiTerminalBackend,
+            tuiTerminalBackendManualIO,
             workspaceTodoControls,
             workspaceTodosChecklistStyle,
         ]
@@ -234,6 +239,23 @@ public struct BetaFeaturesSection: View {
         }
     }
 
+    @ViewBuilder
+    private var tuiTerminalBackendManualIORow: some View {
+        SettingsCardRow(
+            configurationReview: .settingsOnly,
+            searchAnchorID: "setting:betaFeatures:tuiTerminalBackendManualIO",
+            String(localized: "settings.betaFeatures.tuiTerminalBackendManualIO", defaultValue: "cmux-tui Manual-IO Data Path"),
+            subtitle: tuiTerminalBackendManualIO.current
+                ? String(localized: "settings.betaFeatures.tuiTerminalBackendManualIO.subtitleOn", defaultValue: "Daemon-backed terminals feed bytes straight into the Ghostty surface (no attach subprocess in the pane). Requires the cmux-tui Terminal Backend toggle.")
+                : String(localized: "settings.betaFeatures.tuiTerminalBackendManualIO.subtitleOff", defaultValue: "Daemon-backed terminals keep running the attach client as the surface command.")
+        ) {
+            Toggle("", isOn: Binding(get: { tuiTerminalBackendManualIO.current }, set: { tuiTerminalBackendManualIO.set($0) }))
+                .labelsHidden()
+                .controlSize(.small)
+                .accessibilityIdentifier("SettingsBetaTuiTerminalBackendManualIOToggle")
+        }
+    }
+
 }
 
 /// Small warning callout with a yellow triangle, used at the top of

Packages/macOS/CmuxTerminal/Sources/CmuxTerminal/Surface/TerminalSurface+Input.swift

@@ -660,7 +660,8 @@ extension TerminalSurface {
         manualIONoReflow = value
     }
 
-    /// Enqueues remote tmux `%output` for the terminal parser.
+    /// Enqueues remote output (tmux `%output`, tui pipe-io bytes) for the
+    /// terminal parser.
     ///
     /// The native parser runs on the surface generation's FIFO output lane and
     /// this method returns without waiting for Ghostty's renderer-state mutex.

Resources/Localizable.xcstrings

@@ -174903,6 +174903,27 @@
         }
       }
     },
+    "settings.betaFeatures.tuiTerminalBackendManualIO.subtitleOn": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "Daemon-backed terminals feed bytes straight into the Ghostty surface (no attach subprocess in the pane). Requires the cmux-tui Terminal Backend toggle." } },
+        "ja": { "stringUnit": { "state": "translated", "value": "デーモン管理のターミナルがGhosttyサーフェスへ直接バイトを送ります（ペイン内にattachサブプロセスなし）。cmux-tuiターミナルバックエンドの有効化が必要です。" } }
+      }
+    },
+    "settings.betaFeatures.tuiTerminalBackendManualIO.subtitleOff": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "Daemon-backed terminals keep running the attach client as the surface command." } },
+        "ja": { "stringUnit": { "state": "translated", "value": "デーモン管理のターミナルは引き続きattachクライアントをサーフェスコマンドとして実行します。" } }
+      }
+    },
+    "settings.betaFeatures.tuiTerminalBackendManualIO": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "cmux-tui Manual-IO Data Path" } },
+        "ja": { "stringUnit": { "state": "translated", "value": "cmux-tui マニュアルIOデータパス" } }
+      }
+    },
     "settings.betaFeatures.warning": {
       "extractionState": "manual",
       "localizations": {
@@ -254478,6 +254499,48 @@
         }
       }
     },
+    "tui.overlay.reconnecting.title": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "Reconnecting to the terminal session" } },
+        "ja": { "stringUnit": { "state": "translated", "value": "ターミナルセッションに再接続中" } }
+      }
+    },
+    "tui.overlay.reconnecting.detail": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "The session daemon is unreachable (attempt %lld). The terminal shows its last state; input is paused." } },
+        "ja": { "stringUnit": { "state": "translated", "value": "セッションデーモンに接続できません（試行 %lld 回目）。ターミナルは最後の状態を表示しており、入力は一時停止中です。" } }
+      }
+    },
+    "tui.overlay.failed.title": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "Terminal backend unavailable" } },
+        "ja": { "stringUnit": { "state": "translated", "value": "ターミナルバックエンドを利用できません" } }
+      }
+    },
+    "tui.overlay.failed.detail": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "The relay for this daemon-backed terminal keeps failing. Check the cmux-tui binary path in Settings, then retry." } },
+        "ja": { "stringUnit": { "state": "translated", "value": "デーモン管理ターミナルのリレーが繰り返し失敗しています。設定でcmux-tuiバイナリのパスを確認してから再試行してください。" } }
+      }
+    },
+    "tui.overlay.ended.title": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "Terminal session ended" } },
+        "ja": { "stringUnit": { "state": "translated", "value": "ターミナルセッションが終了しました" } }
+      }
+    },
+    "tui.overlay.ended.detail": {
+      "extractionState": "manual",
+      "localizations": {
+        "en": { "stringUnit": { "state": "translated", "value": "The daemon-backed terminal has ended. Close the tab, or keep it to read the final screen." } },
+        "ja": { "stringUnit": { "state": "translated", "value": "デーモン管理のターミナルが終了しました。タブを閉じるか、最後の画面を確認するために残せます。" } }
+      }
+    },
     "uiTest.bonsplit.action.title": {
       "localizations": {
         "en": {