diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 422e68d..06020ba 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -92,8 +92,12 @@ android {
             it.jvmArgs("--add-exports=java.base/jdk.internal.access=ALL-UNNAMED", "--add-opens=java.base/java.io=ALL-UNNAMED")
             // One JVM per test class: Robolectric apps in one JVM share background work and settings files.
             it.forkEvery = 1
-            // Local runs may use several test JVMs (-Ptest.forks=N); CI leaves the default of one.
-            providers.gradleProperty("test.forks").orNull?.toIntOrNull()?.let { n -> it.maxParallelForks = n }
+            // Local runs use a test JVM per four cores, at most four (each Robolectric JVM holds about 1 GB; six ran a
+            // 32 GB PC out of memory). CI keeps one: parallel suites on a runner missed their 30 s waits.
+            // -Ptest.forks=N overrides both.
+            it.maxParallelForks = providers.gradleProperty("test.forks").orNull?.toIntOrNull()
+                ?: if (providers.environmentVariable("CI").isPresent) 1
+                else (Runtime.getRuntime().availableProcessors() / 4).coerceIn(1, 4)
             // Design-review screenshots: ./gradlew :app:testDebugUnitTest --tests '*ScreenshotTest' -Pscreenshots.dir=<folder>
             providers.gradleProperty("screenshots.dir").orNull?.let { dir -> it.systemProperty("screenshots.dir", dir) }
         }
diff --git a/app/src/test/kotlin/com/apollof/protocoltracker/ui/today/TodayWeekPagerTest.kt b/app/src/test/kotlin/com/apollof/protocoltracker/ui/today/TodayWeekPagerTest.kt
index 3cf893f..0a9375e 100644
--- a/app/src/test/kotlin/com/apollof/protocoltracker/ui/today/TodayWeekPagerTest.kt
+++ b/app/src/test/kotlin/com/apollof/protocoltracker/ui/today/TodayWeekPagerTest.kt
@@ -112,6 +112,7 @@ class TodayWeekPagerTest {
         compose.waitUntil(15_000) { compose.onAllNodes(dayCell(lastWeek)).fetchSemanticsNodes().isNotEmpty() }
         compose.onNode(dayCell(lastWeek)).performSemanticsAction(SemanticsActions.OnClick)
         compose.waitUntil(15_000) { hasText("Back to today") && hasText("1 NOT LOGGED") }
+        compose.waitForIdle() // the day switch cross-fades: the old day stays in the tree until it ends
         assertTrue(compose.onAllNodesWithText("Missed", substring = true).fetchSemanticsNodes().isEmpty())
         // It can still be checked off, at its planned time.
         compose.onNodeWithContentDescription("Mark Test C taken").performScrollTo().performClick()