diff --git a/core/deployment/src/main/java/io/quarkus/deployment/dev/DevModeContext.java b/core/deployment/src/main/java/io/quarkus/deployment/dev/DevModeContext.java
index 039ada1dd76a4..fa8e122d382e4 100644
--- a/core/deployment/src/main/java/io/quarkus/deployment/dev/DevModeContext.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/dev/DevModeContext.java
@@ -312,6 +312,12 @@ public Optional<CompilationUnit> getTest() {
             return Optional.ofNullable(test);
         }
 
+        public void addSourcePathFirst(String path) {
+            String absolutePath = Paths.get(path).isAbsolute() ? path
+                    : (projectDirectory + File.separator + path);
+            this.main.sourcePaths = this.main.sourcePaths.addFirst(Paths.get(absolutePath));
+        }
+
         public static class Builder {
 
             private ArtifactKey appArtifactKey;
diff --git a/core/deployment/src/main/java/io/quarkus/deployment/dev/IsolatedDevModeMain.java b/core/deployment/src/main/java/io/quarkus/deployment/dev/IsolatedDevModeMain.java
index 0792198e44625..9a8761cf134d9 100644
--- a/core/deployment/src/main/java/io/quarkus/deployment/dev/IsolatedDevModeMain.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/dev/IsolatedDevModeMain.java
@@ -1,7 +1,6 @@
 package io.quarkus.deployment.dev;
 
 import static io.quarkus.deployment.dev.testing.MessageFormat.BLUE;
-import static java.util.Collections.singleton;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -444,7 +443,7 @@ public boolean test(String s) {
                                     module.getSourceParents(),
                                     Paths.get(module.getPreBuildOutputDir()),
                                     Paths.get(module.getTargetDir()),
-                                    sourcePath -> module.addSourcePaths(singleton(sourcePath.toAbsolutePath().toString()))));
+                                    sourcePath -> module.addSourcePathFirst(sourcePath.toAbsolutePath().toString())));
                 }
             }
             RuntimeUpdatesProcessor.INSTANCE = setupRuntimeCompilation(context, (Path) params.get(APP_ROOT),