diff --git a/app/src/test/java/org/libremediaconverter/convert/ReattachedCleanupTest.kt b/app/src/test/java/org/libremediaconverter/convert/ReattachedCleanupTest.kt
new file mode 100644
index 0000000..52efbad
--- /dev/null
+++ b/app/src/test/java/org/libremediaconverter/convert/ReattachedCleanupTest.kt
@@ -0,0 +1,134 @@
+package org.libremediaconverter.convert
+
+import android.app.Application
+import android.net.Uri
+import androidx.media3.common.util.UnstableApi
+import androidx.work.WorkManager
+import androidx.work.workDataOf
+import kotlinx.coroutines.Dispatchers
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.libremediaconverter.join.JoinState
+import org.libremediaconverter.join.JoinViewModel
+import org.libremediaconverter.model.InputProbe
+import org.libremediaconverter.work.ConcatWorker
+import org.libremediaconverter.work.ConversionWorker
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.RuntimeEnvironment
+import java.io.File
+
+/**
+ * Where the two staging fixes meet: a result nobody started is still a result somebody owns.
+ *
+ * Reattachment hands the user back a job this ViewModel did not start, which means the
+ * ViewModel inherits the staged file along with it — and "Start over" on that file has to
+ * delete it exactly as it would for a conversion run in this process. Neither fix implies
+ * the other: cleanup only reaches a file whose handle was recorded, and reattachment only
+ * records one because it goes through the same `observe()` the normal success path does.
+ * That is a structural claim about one function, which is precisely the kind that a merge
+ * resolving the two changes into different places would quietly break. Hence a test rather
+ * than a comment.
+ *
+ * These run a real `WorkManager` and a real `OutputPublisher` against a real `cacheDir`, so
+ * what is asserted at the end is the filesystem.
+ */
+@UnstableApi
+@RunWith(RobolectricTestRunner::class)
+class ReattachedCleanupTest {
+
+    private lateinit var app: Application
+    private lateinit var publisher: RecordingPublisher
+    private lateinit var workManager: WorkManager
+    private lateinit var staged: File
+
+    @Before
+    fun setUp() {
+        app = RuntimeEnvironment.getApplication()
+        publisher = RecordingPublisher(app)
+        ConversionDependencies.publisher = { publisher }
+        ConversionDependencies.probe = { _, _ -> InputProbe() }
+
+        staged = publisher.createStagingFile("holiday_converted.mp4").apply { writeBytes(ByteArray(4096)) }
+        installTestWorkManager(app, workDataOf(ConversionWorker.KEY_OUTPUT_PATH to staged.absolutePath))
+        workManager = WorkManager.getInstance(app)
+    }
+
+    @After
+    fun tearDown() {
+        ConversionDependencies.reset()
+    }
+
+    /**
+     * The defect end to end, on the JVM: work that finished with no ViewModel left to see it,
+     * and a ViewModel created afterwards that finds it anyway.
+     */
+    @Test
+    fun `a conversion that finished before this ViewModel existed is picked up`() {
+        finishAConversionWithNobodyWatching()
+
+        val viewModel = ConversionViewModel(app, Dispatchers.Unconfined)
+        val converted = awaitState(viewModel.state, "Converted") { it is ConversionState.Converted }
+
+        converted as ConversionState.Converted
+        assertEquals(staged.absolutePath, converted.staged.absolutePath)
+        // The name came back through the job's tags — the only channel WorkManager returns,
+        // since WorkInfo never carries the Data a request was enqueued with.
+        assertEquals("holiday.mp4", converted.input.displayName)
+        assertEquals(4_096L, converted.input.sizeBytes)
+    }
+
+    @Test
+    fun `start over on a reattached conversion deletes the staged file`() {
+        finishAConversionWithNobodyWatching()
+        val viewModel = ConversionViewModel(app, Dispatchers.Unconfined)
+        awaitState(viewModel.state, "Converted") { it is ConversionState.Converted }
+        assertTrue("the reattached result should still be on disk", staged.exists())
+
+        viewModel.reset()
+
+        assertEquals(ConversionState.Idle, viewModel.state.value)
+        assertEquals(
+            "a reattached result is still this ViewModel's to discard",
+            listOf(staged),
+            publisher.discarded,
+        )
+        assertFalse("Start over must not leave a full-size copy in cache", staged.exists())
+    }
+
+    @Test
+    fun `start over on a reattached join deletes the staged file`() {
+        workManager.enqueue(
+            ConcatWorker.request(
+                inputs = listOf(Uri.parse("content://test/one.mp4"), Uri.parse("content://test/two.mp4")),
+                totalBytes = 8_192L,
+            ),
+        ).result.get()
+
+        val viewModel = JoinViewModel(app, Dispatchers.Unconfined)
+        awaitState(viewModel.state, "Joined") { it is JoinState.Joined }
+
+        viewModel.reset()
+
+        assertEquals(listOf(staged), publisher.discarded)
+        assertFalse(staged.exists())
+    }
+
+    /**
+     * A job from a process that is gone: enqueued and finished before any ViewModel exists, so
+     * nothing observed it and nothing recorded its output.
+     */
+    private fun finishAConversionWithNobodyWatching() {
+        workManager.enqueue(
+            ConversionWorker.request(
+                inputUri = Uri.parse("content://test/holiday.mp4"),
+                displayName = "holiday.mp4",
+                sizeBytes = 4_096L,
+            ),
+        ).result.get()
+    }
+}