diff --git a/QuickDrop.xcodeproj/xcshareddata/xcschemes/QuickDrop.xcscheme b/QuickDrop.xcodeproj/xcshareddata/xcschemes/QuickDrop.xcscheme
index 206ddde..d1501c2 100644
--- a/QuickDrop.xcodeproj/xcshareddata/xcschemes/QuickDrop.xcscheme
+++ b/QuickDrop.xcodeproj/xcshareddata/xcschemes/QuickDrop.xcscheme
@@ -40,6 +40,24 @@
       debugDocumentVersioning = "YES"
       debugServiceExtension = "internal"
       allowLocationSimulation = "YES">
+      <PostActions>
+         <ExecutionAction
+            ActionType = "Xcode.IDEStandardExecutionActionsCore.ExecutionActionType.ShellScriptAction">
+            <ActionContent
+               title = "Register dev QuickDrop for Finder Share"
+               scriptText = "&quot;${SRCROOT}/scripts/use-dev-share-extension.sh&quot;&#10;">
+               <EnvironmentBuildable>
+                  <BuildableReference
+                     BuildableIdentifier = "primary"
+                     BlueprintIdentifier = "69DA9A0D29E0BF5100A442DA"
+                     BuildableName = "QuickDrop.app"
+                     BlueprintName = "QuickDrop"
+                     ReferencedContainer = "container:QuickDrop.xcodeproj">
+                  </BuildableReference>
+               </EnvironmentBuildable>
+            </ActionContent>
+         </ExecutionAction>
+      </PostActions>
       <BuildableProductRunnable
          runnableDebuggingMode = "0">
          <BuildableReference
diff --git a/scripts/use-dev-share-extension.sh b/scripts/use-dev-share-extension.sh
new file mode 100755
index 0000000..9412060
--- /dev/null
+++ b/scripts/use-dev-share-extension.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+#
+# Make Finder > Share > QuickDrop use the app Xcode just built (not a stale Release/archive copy).
+#
+# macOS LaunchServices registers EVERY QuickDrop.app on disk that shares the bundle id
+# (com.leonboettger.neardrop) -- Debug build, Release build, archives, old DerivedData, ... -- and the
+# share sheet then picks among those duplicates heuristically, so a stale copy can run instead of the
+# one you just built. This script makes the freshly built app the ONLY registered copy of that bundle id.
+#
+# Usage:
+#   - Standalone:  scripts/use-dev-share-extension.sh        (re-points Finder at the newest Debug build)
+#   - Xcode:       add as a Run post-action (Product > Scheme > Edit Scheme > Run > Post-actions >
+#                  "+" > New Run Script Action; "Provide build settings from: QuickDrop"; paste:
+#                      "${SRCROOT}/scripts/use-dev-share-extension.sh"
+#                  Post-actions run outside the build sandbox, so lsregister/mdfind work there even
+#                  though ENABLE_USER_SCRIPT_SANDBOXING is YES for build phases.
+#
+# `set -u` (not -e): a transient lsregister hiccup shouldn't fail the Xcode Run post-action (red dialog).
+set -u
+
+LSREGISTER="/System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister"
+BUNDLE_ID="com.leonboettger.neardrop"
+
+# Prefer the app Xcode just built (post-action provides these); else the newest Debug build on disk.
+APP=""
+if [ "${BUILT_PRODUCTS_DIR:-}" != "" ] && [ "${WRAPPER_NAME:-}" != "" ] && [ -d "${BUILT_PRODUCTS_DIR}/${WRAPPER_NAME}" ]; then
+  APP="${BUILT_PRODUCTS_DIR}/${WRAPPER_NAME}"
+else
+  APP="$(mdfind "kMDItemCFBundleIdentifier == '${BUNDLE_ID}'" 2>/dev/null | grep '/Build/Products/Debug/QuickDrop.app$' | head -1)"
+fi
+
+if [ -z "${APP}" ] || [ ! -d "${APP}" ]; then
+  echo "use-dev-share-extension: no QuickDrop Debug build found -- build it in Xcode first." >&2
+  exit 0
+fi
+
+# Unregister every OTHER on-disk copy of the bundle id, then (re)register only this one.
+mdfind "kMDItemCFBundleIdentifier == '${BUNDLE_ID}'" 2>/dev/null | while IFS= read -r other; do
+  [ "${other}" = "${APP}" ] && continue
+  "${LSREGISTER}" -u "${other}" 2>/dev/null || true
+done
+"${LSREGISTER}" -f "${APP}"
+
+# Drop any stale running extension so the next Share rebuilds against the fresh registration.
+pkill -f "${BUNDLE_ID}.ShareExtension" 2>/dev/null || true
+
+echo "use-dev-share-extension: Finder Share -> QuickDrop now points at:"
+echo "  ${APP}"