diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e2598927b931..782dc8eab5f1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -153,8 +153,9 @@ jobs:
     timeout-minutes: 45
     env:
       CMUX_SKIP_ZIG_BUILD: "1"
-      # Keep Swift crash backtraces from opening the 30s interactive prompt in CI.
-      SWIFT_BACKTRACE: "interactive=no,color=no"
+      # XCTest app-host crashes can leave xcodebuild waiting in Swift's crash
+      # backtracer until the job timeout. Disable the crash catcher entirely.
+      SWIFT_BACKTRACE: "enable=no"
     steps:
       - name: Checkout
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
diff --git a/cmux.xcodeproj/xcshareddata/xcschemes/cmux-ci.xcscheme b/cmux.xcodeproj/xcshareddata/xcschemes/cmux-ci.xcscheme
index c47c0d492586..1eaa3d4d8835 100644
--- a/cmux.xcodeproj/xcshareddata/xcschemes/cmux-ci.xcscheme
+++ b/cmux.xcodeproj/xcshareddata/xcschemes/cmux-ci.xcscheme
@@ -22,6 +22,9 @@
     <MacroExpansion>
       <BuildableReference BuildableIdentifier="primary" BlueprintIdentifier="A5001050" BuildableName="cmux.app" BlueprintName="cmux" ReferencedContainer="container:cmux.xcodeproj"/>
     </MacroExpansion>
+    <EnvironmentVariables>
+      <EnvironmentVariable key="SWIFT_BACKTRACE" value="enable=no" isEnabled="YES"/>
+    </EnvironmentVariables>
   </TestAction>
   <LaunchAction buildConfiguration="Debug" selectedDebuggerIdentifier="Xcode.DebuggerFoundation.Debugger.LLDB" selectedLauncherIdentifier="Xcode.DebuggerFoundation.Launcher.LLDB" launchStyle="0" useCustomWorkingDirectory="NO" ignoresPersistentStateOnLaunch="YES" debugDocumentVersioning="YES" allowLocationSimulation="YES">
     <BuildableProductRunnable runnableDebuggingMode="0">
diff --git a/cmux.xcodeproj/xcshareddata/xcschemes/cmux-unit.xcscheme b/cmux.xcodeproj/xcshareddata/xcschemes/cmux-unit.xcscheme
index fb51de1fe70d..cca841308d98 100644
--- a/cmux.xcodeproj/xcshareddata/xcschemes/cmux-unit.xcscheme
+++ b/cmux.xcodeproj/xcshareddata/xcschemes/cmux-unit.xcscheme
@@ -20,7 +20,7 @@
       <BuildableReference BuildableIdentifier="primary" BlueprintIdentifier="A5001050" BuildableName="cmux.app" BlueprintName="cmux" ReferencedContainer="container:cmux.xcodeproj"/>
     </MacroExpansion>
     <EnvironmentVariables>
-      <EnvironmentVariable key="SWIFT_BACKTRACE" value="interactive=no,color=no" isEnabled="YES"/>
+      <EnvironmentVariable key="SWIFT_BACKTRACE" value="enable=no" isEnabled="YES"/>
     </EnvironmentVariables>
   </TestAction>
   <LaunchAction buildConfiguration="Debug" selectedDebuggerIdentifier="Xcode.DebuggerFoundation.Debugger.LLDB" selectedLauncherIdentifier="Xcode.DebuggerFoundation.Launcher.LLDB" launchStyle="0" useCustomWorkingDirectory="NO" ignoresPersistentStateOnLaunch="YES" debugDocumentVersioning="YES" allowLocationSimulation="YES">
diff --git a/cmux.xcodeproj/xcshareddata/xcschemes/cmux.xcscheme b/cmux.xcodeproj/xcshareddata/xcschemes/cmux.xcscheme
index 8baf53212a44..eba9679f4d61 100644
--- a/cmux.xcodeproj/xcshareddata/xcschemes/cmux.xcscheme
+++ b/cmux.xcodeproj/xcshareddata/xcschemes/cmux.xcscheme
@@ -16,6 +16,9 @@
     <MacroExpansion>
       <BuildableReference BuildableIdentifier="primary" BlueprintIdentifier="A5001050" BuildableName="cmux.app" BlueprintName="cmux" ReferencedContainer="container:cmux.xcodeproj"/>
     </MacroExpansion>
+    <EnvironmentVariables>
+      <EnvironmentVariable key="SWIFT_BACKTRACE" value="enable=no" isEnabled="YES"/>
+    </EnvironmentVariables>
   </TestAction>
   <LaunchAction buildConfiguration="Release" selectedDebuggerIdentifier="Xcode.DebuggerFoundation.Debugger.LLDB" selectedLauncherIdentifier="Xcode.DebuggerFoundation.Launcher.LLDB" launchStyle="0" useCustomWorkingDirectory="NO" ignoresPersistentStateOnLaunch="NO" debugDocumentVersioning="YES" allowLocationSimulation="YES">
     <BuildableProductRunnable runnableDebuggingMode="0">