# UNDF: UNDF-2026-000000469
--- a/core/deployment/src/main/java/io/quarkus/deployment/dev/RuntimeUpdatesProcessor.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/dev/RuntimeUpdatesProcessor.java
@@ -817,7 +817,7 @@ public class RuntimeUpdatesProcessor implements HotReplacementContext, Closeable

         for (ChangeDetectionResult changeDetectionResult : changeDetectionResults) {
-            final List<Path> moduleChangedSourceFilePaths = new ArrayList<>();
+            final Set<Path> moduleChangedSourceFilePaths = new LinkedHashSet<>();
             for (RecompilableLocationsBySourcePath recompilableLocationsBySourcePath : changeDetectionResult
                     .changedLocations()) {
                 Path sourcePath = recompilableLocationsBySourcePath.sourcePath();
@@ -936,7 +936,7 @@ public class RuntimeUpdatesProcessor implements HotReplacementContext, Closeable
     private void checkForClassFilesChangesInModule(DevModeContext.ModuleInfo module,
-            List<Path> moduleChangedSourceFiles,
+            Set<Path> moduleChangedSourceFiles,
             boolean isInitialRun, ClassScanResult classScanResult,
             Function<DevModeContext.ModuleInfo, DevModeContext.CompilationUnit> cuf, TimestampSet timestampSet) {

@@ -1001,7 +1001,7 @@ public class RuntimeUpdatesProcessor implements HotReplacementContext, Closeable
     private Path retrieveSourceFilePathForClassFile(Path classFilePath,
-            List<Path> moduleChangedSourceFiles,
+            Set<Path> moduleChangedSourceFiles,
             DevModeContext.ModuleInfo module,
             Function<DevModeContext.ModuleInfo, DevModeContext.CompilationUnit> cuf,
             TimestampSet timestampSet, boolean forceRefresh) {