diff --git a/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesRegistryBuildItem.java b/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesRegistryBuildItem.java
index ea4e83fbb0e27..c01c2953e16e9 100644
--- a/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesRegistryBuildItem.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesRegistryBuildItem.java
@@ -125,7 +125,7 @@ private void reallyStart(DevServicesResultBuildItem request, List<DevServicesCus
             startable.start();
 
             RunningService service = new RunningService(request.getName(), request.getDescription(),
-                    request.getConfig(startable), startable.getContainerId(), startable);
+                    request.getConfig(startable), request.getOverrideConfig(startable), startable.getContainerId(), startable);
             this.addRunningService(request.getName(), request.getServiceName(), request.getServiceConfig(), service);
 
             compressor.close();
diff --git a/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesResultBuildItem.java b/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesResultBuildItem.java
index 5994cf4cc640b..5242abcf640db 100644
--- a/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesResultBuildItem.java
+++ b/core/deployment/src/main/java/io/quarkus/deployment/builditem/DevServicesResultBuildItem.java
@@ -6,6 +6,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Set;
 import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Supplier;
@@ -77,6 +78,7 @@ public final class DevServicesResultBuildItem extends MultiBuildItem {
      * A map of application config that is dependent on the started service
      */
     private final Map<String, Function<Startable, String>> applicationConfigProvider;
+    private final Set<String> highPriorityConfig;
 
     public static DiscoveredServiceBuilder discovered() {
         return new DiscoveredServiceBuilder();
@@ -106,6 +108,7 @@ public DevServicesResultBuildItem(String name, String description, String contai
         this.serviceName = null;
         this.serviceConfig = null;
         this.applicationConfigProvider = null;
+        this.highPriorityConfig = null;
         this.startableSupplier = null;
         this.postStartAction = null;
     }
@@ -121,7 +124,7 @@ public DevServicesResultBuildItem(String name,
             Map<String, String> config,
             Supplier<Startable> startableSupplier,
             Consumer<Startable> postStartAction,
-            Map<String, Function<Startable, String>> applicationConfigProvider) {
+            Map<String, Function<Startable, String>> applicationConfigProvider, Set<String> highPriorityConfig) {
         this.name = name;
         this.description = description;
         this.containerId = null;
@@ -131,6 +134,7 @@ public DevServicesResultBuildItem(String name,
         this.startableSupplier = startableSupplier;
         this.postStartAction = postStartAction;
         this.applicationConfigProvider = applicationConfigProvider;
+        this.highPriorityConfig = highPriorityConfig;
     }
 
     public String getName() {
@@ -175,6 +179,7 @@ public Map<String, Function<Startable, String>> getApplicationConfigProvider() {
 
     public Map<String, String> getConfig(Startable startable) {
         SupplierMap<String, String> map = new SupplierMap<>();
+        // To make sure static config does make it into a config source, include it here
         if (config != null && !config.isEmpty()) {
             map.putAll(config);
         }
@@ -186,6 +191,22 @@ public Map<String, String> getConfig(Startable startable) {
         return map;
     }
 
+    /**
+     * @deprecated Subject to changes due to <a href="https://github.com/quarkusio/quarkus/pull/51209">#51209</a>
+     */
+    @Deprecated(forRemoval = true)
+    public Map<String, String> getOverrideConfig(Startable startable) {
+
+        SupplierMap<String, String> map = new SupplierMap<>();
+
+        if (highPriorityConfig != null) {
+            for (String key : highPriorityConfig) {
+                map.put(key, () -> applicationConfigProvider.get(key).apply(startable));
+            }
+        }
+        return map;
+    }
+
     public static class DiscoveredServiceBuilder {
         private String name;
         private String containerId;
@@ -226,10 +247,8 @@ public DevServicesResultBuildItem build() {
     }
 
     public static class OwnedServiceBuilder<T extends Startable> {
-
         private static final String IO_QUARKUS_DEVSERVICES_CONFIG_BUILDER_CLASS = "io.quarkus.devservice.runtime.config.DevServicesConfigBuilder";
-        private static final boolean CONFIG_BUILDER_AVAILABLE = isClassAvailable(
-                IO_QUARKUS_DEVSERVICES_CONFIG_BUILDER_CLASS);
+        private static final boolean CONFIG_BUILDER_AVAILABLE = isClassAvailable(IO_QUARKUS_DEVSERVICES_CONFIG_BUILDER_CLASS);
 
         private String name;
         private String description;
@@ -239,6 +258,7 @@ public static class OwnedServiceBuilder<T extends Startable> {
         private Supplier<? extends Startable> startableSupplier;
         private Consumer<? extends Startable> postStartAction;
         private Map<String, Function<Startable, String>> applicationConfigProvider;
+        private Set<String> highPriorityConfig;
 
         public OwnedServiceBuilder<T> name(String name) {
             this.name = name;
@@ -286,6 +306,15 @@ public OwnedServiceBuilder<T> postStartHook(Consumer<T> postStartAction) {
             return this;
         }
 
+        /**
+         * @deprecated Subject to changes due to <a href="https://github.com/quarkusio/quarkus/pull/51209">#51209</a>
+         */
+        @Deprecated(forRemoval = true)
+        public OwnedServiceBuilder<T> highPriorityConfig(Set<String> highPriorityConfig) {
+            this.highPriorityConfig = highPriorityConfig;
+            return this;
+        }
+
         /**
          * Provides config to inject into the config system. If you've got values that don't change, use config(), and if you've
          * got values that you'll only know after starting the container, use configProvider() and provide a map of
@@ -306,7 +335,7 @@ public DevServicesResultBuildItem build() {
             return new DevServicesResultBuildItem(name, description, serviceName, serviceConfig, config,
                     (Supplier<Startable>) startableSupplier,
                     (Consumer<Startable>) postStartAction,
-                    applicationConfigProvider);
+                    applicationConfigProvider, highPriorityConfig);
         }
 
         private static boolean isClassAvailable(String className) {
diff --git a/core/runtime/src/main/java/io/quarkus/devservices/crossclassloader/runtime/RunningService.java b/core/runtime/src/main/java/io/quarkus/devservices/crossclassloader/runtime/RunningService.java
index 479445a5891ad..31ac7dd66bf9c 100644
--- a/core/runtime/src/main/java/io/quarkus/devservices/crossclassloader/runtime/RunningService.java
+++ b/core/runtime/src/main/java/io/quarkus/devservices/crossclassloader/runtime/RunningService.java
@@ -16,14 +16,17 @@ public final class RunningService implements Closeable {
     private final String feature;
     private final String description;
     private final Map<String, String> configs;
+    private final Map<String, String> overrideConfigs;
     private final String containerId;
     private final Closeable closeable;
 
-    public RunningService(String feature, String description, Map<String, String> configs, String containerId,
+    public RunningService(String feature, String description, Map<String, String> configs, Map<String, String> overrideConfig,
+            String containerId,
             Closeable closeable) {
         this.feature = feature;
         this.description = description;
         this.configs = configs;
+        this.overrideConfigs = overrideConfig;
         this.containerId = containerId;
         this.closeable = closeable;
     }
@@ -45,8 +48,15 @@ public Map<String, String> configs() {
         return configs;
     }
 
+    /**
+     * @deprecated Subject to changes due to <a href="https://github.com/quarkusio/quarkus/pull/51209">#51209</a>
+     */
+    @Deprecated(forRemoval = true)
+    public Map<String, String> overrideConfigs() {
+        return overrideConfigs;
+    }
+
     public String containerId() {
         return containerId;
     }
-
 }
diff --git a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/DevServicesLambdaProcessor.java b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/DevServicesLambdaProcessor.java
index e7c71bcedd7a3..e340ba29ce48d 100644
--- a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/DevServicesLambdaProcessor.java
+++ b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/DevServicesLambdaProcessor.java
@@ -5,12 +5,15 @@
 import java.io.IOException;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
 
+import org.eclipse.microprofile.config.ConfigProvider;
 import org.jboss.logging.Logger;
 
 import io.quarkus.amazon.lambda.runtime.AmazonLambdaApi;
 import io.quarkus.amazon.lambda.runtime.LambdaHotReplacementRecorder;
 import io.quarkus.amazon.lambda.runtime.MockEventServer;
+import io.quarkus.amazon.lambda.runtime.MockEventServerConfig;
 import io.quarkus.deployment.Feature;
 import io.quarkus.deployment.IsLiveReloadSupportedByLaunchMode;
 import io.quarkus.deployment.IsProduction;
@@ -51,7 +54,7 @@ private boolean legacyTestingEnabled() {
     @Produce(ServiceStartBuildItem.class)
     @BuildStep(onlyIfNot = IsProduction.class) // This is required for testing so run it even if devservices.enabled=false
     public void startEventServer(LaunchModeBuildItem launchModeBuildItem,
-            LambdaConfig config,
+            LambdaBuildConfig config,
             Optional<EventServerOverrideBuildItem> override,
             BuildProducer<DevServicesResultBuildItem> devServicePropertiesProducer) {
         LaunchMode launchMode = launchModeBuildItem.getLaunchMode();
@@ -70,9 +73,8 @@ public void startEventServer(LaunchModeBuildItem launchModeBuildItem,
             server = new MockEventServer();
         }
 
-        int configuredPort = launchMode == LaunchMode.TEST ? config.mockEventServer().testPort()
-                : config.mockEventServer().devPort();
-        String portPropertySuffix = launchMode == LaunchMode.TEST ? "test-port" : "dev-port";
+        boolean isTest = launchMode == LaunchMode.TEST;
+        String portPropertySuffix = isTest ? "test-port" : "dev-port";
         String propName = "quarkus.lambda.mock-event-server." + portPropertySuffix;
 
         // No compose support, and no using of external services, so no need to discover existing services
@@ -80,8 +82,8 @@ public void startEventServer(LaunchModeBuildItem launchModeBuildItem,
         DevServicesResultBuildItem buildItem = DevServicesResultBuildItem.owned().feature(Feature.AMAZON_LAMBDA)
                 .serviceName(Feature.AMAZON_LAMBDA.getName())
                 .serviceConfig(config)
-                .startable(() -> new StartableEventServer(
-                        server, configuredPort))
+                .startable(() -> new StartableEventServer(server, propName, isTest))
+                .highPriorityConfig(Set.of(propName)) // Pass through the external config for the port, so that it can be overridden if it's an ephemeral port
                 .configProvider(
                         Map.of(propName, s -> String.valueOf(s.getExposedPort()),
                                 AmazonLambdaApi.QUARKUS_INTERNAL_AWS_LAMBDA_TEST_API,
@@ -93,17 +95,26 @@ public void startEventServer(LaunchModeBuildItem launchModeBuildItem,
     }
 
     private static class StartableEventServer implements Startable {
-
         private final MockEventServer server;
-        private final int configuredPort;
+        private final String propName;
+        private final boolean isTest;
 
-        public StartableEventServer(MockEventServer server, int configuredPort) {
+        public StartableEventServer(MockEventServer server, String propName, boolean isTest) {
             this.server = server;
-            this.configuredPort = configuredPort;
+            this.propName = propName;
+            this.isTest = isTest;
         }
 
         @Override
         public void start() {
+            // Technically, we shouldn't peek at the runtime config, but every dev service does it
+            // However, we won't get defaults, so we need to fill our own in
+            int port = isTest ? Integer.parseInt(MockEventServerConfig.TEST_PORT)
+                    : Integer.parseInt(MockEventServerConfig.DEV_PORT);
+            int configuredPort = ConfigProvider.getConfig().getOptionalValue(propName, Integer.class)
+                    .or(() -> Optional.of(port))
+                    .get();
+
             server.start(configuredPort);
             log.debugf("Starting event server on port %d", configuredPort);
         }
diff --git a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaBuildConfig.java b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaBuildConfig.java
new file mode 100644
index 0000000000000..cb606291c8c7a
--- /dev/null
+++ b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaBuildConfig.java
@@ -0,0 +1,16 @@
+package io.quarkus.amazon.lambda.deployment;
+
+import io.quarkus.runtime.annotations.ConfigPhase;
+import io.quarkus.runtime.annotations.ConfigRoot;
+import io.smallrye.config.ConfigMapping;
+
+@ConfigRoot(phase = ConfigPhase.BUILD_TIME)
+@ConfigMapping(prefix = "quarkus.lambda")
+public interface LambdaBuildConfig {
+
+    /**
+     * Configuration for the mock event server that is run
+     * in dev mode and test mode
+     */
+    MockEventServerBuildConfig mockEventServer();
+}
diff --git a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerConfig.java b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerBuildConfig.java
similarity index 55%
rename from extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerConfig.java
rename to extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerBuildConfig.java
index c2aa666e9810f..4c6094e383e4b 100644
--- a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerConfig.java
+++ b/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/MockEventServerBuildConfig.java
@@ -6,22 +6,11 @@
  * Configuration for the mock event server that is run
  * in dev mode and test mode
  */
-public interface MockEventServerConfig {
+public interface MockEventServerBuildConfig {
     /**
      * Setting to true will start event server even if quarkus.devservices.enabled=false
      */
     @WithDefault("true")
     boolean enabled();
 
-    /**
-     * Port to access mock event server in dev mode
-     */
-    @WithDefault("8080")
-    int devPort();
-
-    /**
-     * Port to access mock event server in dev mode
-     */
-    @WithDefault("8081")
-    int testPort();
 }
diff --git a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaConfig.java b/extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/LambdaConfig.java
similarity index 80%
rename from extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaConfig.java
rename to extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/LambdaConfig.java
index 36c15e3e3a77e..bc73bc8e36f9b 100644
--- a/extensions/amazon-lambda/common-deployment/src/main/java/io/quarkus/amazon/lambda/deployment/LambdaConfig.java
+++ b/extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/LambdaConfig.java
@@ -1,10 +1,10 @@
-package io.quarkus.amazon.lambda.deployment;
+package io.quarkus.amazon.lambda.runtime;
 
 import io.quarkus.runtime.annotations.ConfigPhase;
 import io.quarkus.runtime.annotations.ConfigRoot;
 import io.smallrye.config.ConfigMapping;
 
-@ConfigRoot(phase = ConfigPhase.BUILD_TIME)
+@ConfigRoot(phase = ConfigPhase.RUN_TIME)
 @ConfigMapping(prefix = "quarkus.lambda")
 public interface LambdaConfig {
 
@@ -13,4 +13,5 @@ public interface LambdaConfig {
      * in dev mode and test mode
      */
     MockEventServerConfig mockEventServer();
+
 }
diff --git a/extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/MockEventServerConfig.java b/extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/MockEventServerConfig.java
new file mode 100644
index 0000000000000..cd56f4bbc3cdd
--- /dev/null
+++ b/extensions/amazon-lambda/common-runtime/src/main/java/io/quarkus/amazon/lambda/runtime/MockEventServerConfig.java
@@ -0,0 +1,29 @@
+package io.quarkus.amazon.lambda.runtime;
+
+import io.quarkus.runtime.annotations.ConfigPhase;
+import io.quarkus.runtime.annotations.ConfigRoot;
+import io.smallrye.config.ConfigMapping;
+import io.smallrye.config.WithDefault;
+
+/**
+ * Configuration for the mock event server that is run
+ * in dev mode and test mode
+ */
+@ConfigRoot(phase = ConfigPhase.RUN_TIME)
+@ConfigMapping(prefix = "quarkus.lambda")
+public interface MockEventServerConfig {
+    static final String DEV_PORT = "8080";
+    static final String TEST_PORT = "8081";
+
+    /**
+     * Port to access mock event server in dev mode
+     */
+    @WithDefault(DEV_PORT)
+    int devPort();
+
+    /**
+     * Port to access mock event server in dev mode
+     */
+    @WithDefault(TEST_PORT)
+    int testPort();
+}
diff --git a/extensions/devservices/deployment/src/main/java/io/quarkus/devservices/deployment/DevServicesProcessor.java b/extensions/devservices/deployment/src/main/java/io/quarkus/devservices/deployment/DevServicesProcessor.java
index 4f0de87a56715..3413a1f318392 100644
--- a/extensions/devservices/deployment/src/main/java/io/quarkus/devservices/deployment/DevServicesProcessor.java
+++ b/extensions/devservices/deployment/src/main/java/io/quarkus/devservices/deployment/DevServicesProcessor.java
@@ -154,19 +154,18 @@ DevServicesRegistryBuildItem devServicesRegistry(LaunchModeBuildItem launchMode,
 
     // Because the devservices runtime module is new and the ecosystem needs time to catch up, don't die if the runtime module isn't available
     @BuildStep(onlyIf = { IsRuntimeModuleAvailable.class })
-    public RunTimeConfigBuilderBuildItem registerDevResourcesConfigSource(
-            List<DevServicesResultBuildItem> devServicesRequestBuildItems) {
+    public void registerDevResourcesConfigSource(BuildProducer<RunTimeConfigBuilderBuildItem> runtimeConfigBuilders) {
         // Once all the dev services are registered, we can share config
         try {
             // Use reflection, since we don't have an explicit dependency on the runtime module (because dependent extensions may not have that dependency)
-            Class<?> builderClass = Class
-                    .forName(IO_QUARKUS_DEVSERVICES_CONFIG_BUILDER_CLASS);
-            return new RunTimeConfigBuilderBuildItem(builderClass);
+            runtimeConfigBuilders
+                    .produce(new RunTimeConfigBuilderBuildItem(Class.forName(IO_QUARKUS_DEVSERVICES_CONFIG_BUILDER_CLASS)));
+            runtimeConfigBuilders.produce(new RunTimeConfigBuilderBuildItem(
+                    Class.forName("io.quarkus.devservice.runtime.config.DevServicesOverrideConfigBuilder")));
         } catch (ClassNotFoundException e) {
             // Should never happen, because of the guard, as long as the runtime module is not a direct dependency of this module
             throw new RuntimeException(e);
         }
-
     }
 
     @BuildStep(onlyIf = { IsDevelopment.class, DevServicesConfig.Enabled.class })
diff --git a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigBuilder.java b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigBuilder.java
index 1aaebfd229194..762364c41cc40 100644
--- a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigBuilder.java
+++ b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigBuilder.java
@@ -13,11 +13,6 @@ public SmallRyeConfigBuilder configBuilder(SmallRyeConfigBuilder builder) {
 
     @Override
     public int priority() {
-        // What's the right priority? This is a cheeky dynamic override, so a high priority seems correct, but dev services are supposed to fill in gaps in existing information.
-        // Dev services should be looking at those sources and not doing anything if there's existing config,
-        // so a very low priority is also arguably correct.
-        // In principle the priority actually shouldn't matter much, but in practice it needs to not be higher than Arquillian config overrides or some tests fail
-
         return 10;
     }
 }
diff --git a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigSource.java b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigSource.java
index 6bea4a2b25208..04cf8617aef0e 100644
--- a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigSource.java
+++ b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesConfigSource.java
@@ -20,7 +20,6 @@ public DevServicesConfigSource(LaunchMode launchMode) {
 
     @Override
     public Set<String> getPropertyNames() {
-        // We could make this more efficient by not invoking the supplier on the other end, but it would need a more complex interface
         Set<String> names = new HashSet<>();
 
         Set<RunningService> allConfig = RunningDevServicesRegistry.INSTANCE.getAllRunningServices(launchMode.name());
@@ -55,7 +54,6 @@ public String getName() {
 
     @Override
     public int getOrdinal() {
-        // See discussion on DevServicesConfigBuilder about what the right value here is
-        return 10;
+        return 240; // a bit less than application properties, because this config should only take effect if nothing is set
     }
 }
diff --git a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigBuilder.java b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigBuilder.java
new file mode 100644
index 0000000000000..fcf065c5f2891
--- /dev/null
+++ b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigBuilder.java
@@ -0,0 +1,22 @@
+package io.quarkus.devservice.runtime.config;
+
+import io.quarkus.runtime.LaunchMode;
+import io.quarkus.runtime.configuration.ConfigBuilder;
+import io.smallrye.config.SmallRyeConfigBuilder;
+
+/**
+ * @deprecated Subject to changes due to <a href="https://github.com/quarkusio/quarkus/pull/51209">#51209</a>
+ */
+@Deprecated(forRemoval = true)
+public class DevServicesOverrideConfigBuilder implements ConfigBuilder {
+
+    @Override
+    public SmallRyeConfigBuilder configBuilder(SmallRyeConfigBuilder builder) {
+        return builder.withSources(new DevServicesOverrideConfigSource(LaunchMode.current()));
+    }
+
+    @Override
+    public int priority() {
+        return 10;
+    }
+}
diff --git a/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigSource.java b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigSource.java
new file mode 100644
index 0000000000000..cd4c9c1554dd3
--- /dev/null
+++ b/extensions/devservices/runtime/src/main/java/io/quarkus/devservice/runtime/config/DevServicesOverrideConfigSource.java
@@ -0,0 +1,65 @@
+package io.quarkus.devservice.runtime.config;
+
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+import org.eclipse.microprofile.config.spi.ConfigSource;
+
+import io.quarkus.devservices.crossclassloader.runtime.RunningDevServicesRegistry;
+import io.quarkus.devservices.crossclassloader.runtime.RunningService;
+import io.quarkus.runtime.LaunchMode;
+
+/**
+ * @deprecated Subject to changes due to <a href="https://github.com/quarkusio/quarkus/pull/51209">#51209</a>
+ */
+@Deprecated(forRemoval = true)
+public class DevServicesOverrideConfigSource implements ConfigSource {
+
+    private final LaunchMode launchMode;
+
+    public DevServicesOverrideConfigSource(LaunchMode launchMode) {
+        this.launchMode = launchMode;
+    }
+
+    @Override
+    public Set<String> getPropertyNames() {
+        // We could make this more efficient by not invoking the supplier on the other end, but it would need a more complex interface
+        Set<String> names = new HashSet<>();
+
+        Set<RunningService> allConfig = RunningDevServicesRegistry.INSTANCE.getAllRunningServices(launchMode.name());
+        if (allConfig != null) {
+            for (RunningService service : allConfig) {
+                Map<String, String> config = service.overrideConfigs();
+                names.addAll(config.keySet());
+            }
+        }
+        return names;
+    }
+
+    @Override
+    public String getValue(String propertyName) {
+        Set<RunningService> allConfig = RunningDevServicesRegistry.INSTANCE.getAllRunningServices(launchMode.name());
+        if (allConfig != null) {
+            for (RunningService service : allConfig) {
+                Map<String, String> config = service.overrideConfigs();
+                String answer = config.get(propertyName);
+                if (answer != null) {
+                    return answer;
+                }
+            }
+        }
+        return null;
+    }
+
+    @Override
+    public String getName() {
+        return "DevServicesOverrideConfigSource";
+    }
+
+    @Override
+    public int getOrdinal() {
+        // This is a dynamic override, so it needs a high priority to be able to override ephemeral port (0) with real values
+        return 410; // a bit more than system properties
+    }
+}
diff --git a/integration-tests/amazon-lambda/src/test/java/io/quarkus/it/amazon/lambda/AmazonLambdaEphemeralPortTestCase.java b/integration-tests/amazon-lambda/src/test/java/io/quarkus/it/amazon/lambda/AmazonLambdaEphemeralPortTestCase.java
index 18b5999fdcab2..acdefad0883da 100644
--- a/integration-tests/amazon-lambda/src/test/java/io/quarkus/it/amazon/lambda/AmazonLambdaEphemeralPortTestCase.java
+++ b/integration-tests/amazon-lambda/src/test/java/io/quarkus/it/amazon/lambda/AmazonLambdaEphemeralPortTestCase.java
@@ -3,14 +3,12 @@
 import static io.restassured.RestAssured.given;
 import static org.hamcrest.CoreMatchers.containsString;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
 import io.quarkus.it.amazon.lambda.profiles.EphemeralPortProfile;
 import io.quarkus.test.junit.QuarkusTest;
 import io.quarkus.test.junit.TestProfile;
 
-@Disabled("Tracked by https://github.com/quarkusio/quarkus/issues/48784")
 @TestProfile(EphemeralPortProfile.class)
 @QuarkusTest
 public class AmazonLambdaEphemeralPortTestCase {