diff --git a/apps/helper/Sources/SimEnclaveHelperKit/InjectionEnv.swift b/apps/helper/Sources/SimEnclaveHelperKit/InjectionEnv.swift
index a7a74f8..33a656f 100644
--- a/apps/helper/Sources/SimEnclaveHelperKit/InjectionEnv.swift
+++ b/apps/helper/Sources/SimEnclaveHelperKit/InjectionEnv.swift
@@ -7,19 +7,29 @@
 /// `SIMBLE_*`) and are set and cleared directly.
 public enum InjectionEnv {
     /// Add `dylib` to a `DYLD_INSERT_LIBRARIES` value exactly once, preserving every other entry.
+    /// An entry already carrying `dylib`'s file name is replaced, so re-arming with a relocated
+    /// slice path never doubles our entry.
     public static func composed(current: String?, adding dylib: String) -> String {
-        var entries = split(current)
-        entries.removeAll { $0 == dylib }
+        let name = fileName(dylib)
+        var entries = split(current).filter { fileName($0) != name }
         entries.append(dylib)
         return entries.joined(separator: ":")
     }
 
     /// Remove `dylib` from a `DYLD_INSERT_LIBRARIES` value, leaving every other tool's entry.
+    /// Matches on the file name, so teardown finds our slice even when its absolute path has since
+    /// moved or the file is gone and only its canonical name is known.
     public static func removed(current: String?, removing dylib: String) -> String {
-        split(current).filter { $0 != dylib }.joined(separator: ":")
+        let name = fileName(dylib)
+        return split(current).filter { fileName($0) != name }.joined(separator: ":")
     }
 
     private static func split(_ value: String?) -> [String] {
         (value ?? "").split(separator: ":").map(String.init).filter { !$0.isEmpty }
     }
+
+    /// The last path component of an insert-list entry, the slice's file name.
+    private static func fileName(_ path: String) -> String {
+        String(path.split(separator: "/").last ?? Substring(path))
+    }
 }
diff --git a/apps/helper/Sources/simenclave-menubar/HelperModel.swift b/apps/helper/Sources/simenclave-menubar/HelperModel.swift
index 0e05dc8..9d51389 100644
--- a/apps/helper/Sources/simenclave-menubar/HelperModel.swift
+++ b/apps/helper/Sources/simenclave-menubar/HelperModel.swift
@@ -254,14 +254,14 @@ final class HelperModel {
     /// cleanup before the helper goes away and a stale port/token cannot mislead a later app.
     func clearInjection() {
         for sim in Self.bootedSimulators() {
-            // Remove only our slice from the shared DYLD list; never blanket-unset it, which would
-            // also drop a peer tool's interposer. Unset the variable only when nothing else is left.
-            if let dylib = Self.interposerDylib(for: sim.platform) {
-                let current = Self.simulatorEnv(sim.udid, "DYLD_INSERT_LIBRARIES")
-                let remaining = InjectionEnv.removed(current: current, removing: dylib)
+            // Remove our slice by its canonical file name, not a locator-resolved path: teardown
+            // must succeed even when the slice moved or was deleted since arming. Write the shared
+            // list only when it carries our entry, leaving a peer tool's interposer alone.
+            if let current = Self.simulatorEnv(sim.udid, "DYLD_INSERT_LIBRARIES") {
+                let remaining = InjectionEnv.removed(current: current, removing: sim.platform.dylibName)
                 if remaining.isEmpty {
                     Self.runSimctl(["spawn", sim.udid, "launchctl", "unsetenv", "DYLD_INSERT_LIBRARIES"])
-                } else if remaining != (current ?? "") {
+                } else if remaining != current {
                     Self.runSimctl(["spawn", sim.udid, "launchctl", "setenv", "DYLD_INSERT_LIBRARIES", remaining])
                 }
             }
diff --git a/apps/helper/Tests/SimEnclaveHelperKitTests/InjectionEnvTests.swift b/apps/helper/Tests/SimEnclaveHelperKitTests/InjectionEnvTests.swift
index 083b5c1..68eac70 100644
--- a/apps/helper/Tests/SimEnclaveHelperKitTests/InjectionEnvTests.swift
+++ b/apps/helper/Tests/SimEnclaveHelperKitTests/InjectionEnvTests.swift
@@ -41,4 +41,22 @@ final class InjectionEnvTests: XCTestCase {
         XCTAssertEqual(InjectionEnv.removed(current: other, removing: mine), other)
         XCTAssertEqual(InjectionEnv.removed(current: nil, removing: mine), "")
     }
+
+    func testComposedDedupesByFileNameAcrossPaths() {
+        // Re-arm from a relocated build: the old path drops by name, the new one lands, no double.
+        let oldPath = "/old/simenclave-interpose.dylib"
+        let newPath = "/new/simenclave-interpose.dylib"
+        XCTAssertEqual(InjectionEnv.composed(current: oldPath, adding: newPath), newPath)
+        XCTAssertEqual(
+            InjectionEnv.composed(current: "\(other):\(oldPath)", adding: newPath),
+            "\(other):\(newPath)")
+    }
+
+    func testRemovedMatchesByFileNameAcrossPaths() {
+        // Locator-independent teardown: remove by canonical name even when the armed path differs.
+        let armed = "/old/simenclave-interpose.dylib"
+        let name = "simenclave-interpose.dylib"
+        XCTAssertEqual(InjectionEnv.removed(current: armed, removing: name), "")
+        XCTAssertEqual(InjectionEnv.removed(current: "\(other):\(armed)", removing: name), other)
+    }
 }