diff --git a/core/deployment/src/main/java/org/jboss/shamrock/deployment/codegen/BytecodeRecorderImpl.java b/core/deployment/src/main/java/org/jboss/shamrock/deployment/codegen/BytecodeRecorderImpl.java
index 62dc4868d313a..d99e6e65b5ae6 100644
--- a/core/deployment/src/main/java/org/jboss/shamrock/deployment/codegen/BytecodeRecorderImpl.java
+++ b/core/deployment/src/main/java/org/jboss/shamrock/deployment/codegen/BytecodeRecorderImpl.java
@@ -36,6 +36,7 @@
 import org.jboss.protean.gizmo.ResultHandle;
 import org.jboss.shamrock.deployment.ClassOutput;
 import org.jboss.shamrock.deployment.ShamrockConfig;
+import org.jboss.shamrock.runtime.ConfiguredValue;
 import org.jboss.shamrock.runtime.ContextObject;
 import org.jboss.shamrock.runtime.InjectionInstance;
 import org.jboss.shamrock.runtime.RuntimeInjector;
@@ -303,9 +304,13 @@ private ResultHandle loadObjectInstance(MethodCreator method, Object param, Map<
                 throw new RuntimeException("Failed to substitute " + param, e);
             }
 
+        } else if (param instanceof ConfiguredValue) {
+            ConfiguredValue val = (ConfiguredValue) param;
+            String value = val.getValue();
+            String key = val.getKey();
+            out = method.newInstance(ofConstructor(ConfiguredValue.class, String.class, String.class), method.load(key), method.load(value));
         } else if (param instanceof String) {
             String configParam = ShamrockConfig.getConfigKey((String) param);
-            out = method.load((String) param);
             if (configParam != null) {
                 ResultHandle config = method.invokeStaticMethod(ofMethod(ConfigProvider.class, "getConfig", Config.class));
                 ResultHandle propName = method.load(configParam);
diff --git a/core/runtime/src/main/java/org/jboss/shamrock/runtime/ConfiguredValue.java b/core/runtime/src/main/java/org/jboss/shamrock/runtime/ConfiguredValue.java
new file mode 100644
index 0000000000000..0af29e60176a0
--- /dev/null
+++ b/core/runtime/src/main/java/org/jboss/shamrock/runtime/ConfiguredValue.java
@@ -0,0 +1,42 @@
+package org.jboss.shamrock.runtime;
+
+import org.eclipse.microprofile.config.Config;
+import org.eclipse.microprofile.config.ConfigProvider;
+
+/**
+ * Represents a value that can be read from MicroProfile config. It is designed to be passed
+ * to Template objects, and as such can be configured at both build and run time.
+ *
+ * The value is determined as follows:
+ *
+ * - If the key is present in MPConfig at runtime, then the runtime value is used
+ * - If the key is present at deployment time, then the deployment time value is used
+ * - Otherwise the default value is used, or null if it was not provided
+ *
+ * TODO: this is a more explicit alternative to the transparent config option provided by ShamrockConfig. We should probably only have one, this is something to revisit later
+ *
+ */
+public class ConfiguredValue {
+
+    private static final Config config = ConfigProvider.getConfig();
+
+    private final String key;
+    private final String defaultValue;
+
+    public ConfiguredValue(String key, String defaultValue) {
+        this.key = key;
+        this.defaultValue = defaultValue;
+    }
+
+    public String getValue() {
+        return config.getOptionalValue(key, String.class).orElse(defaultValue);
+    }
+
+    public String getKey() {
+        return key;
+    }
+
+    public String getDefaultValue() {
+        return defaultValue;
+    }
+}
diff --git a/undertow/deployment/src/main/java/org/jboss/shamrock/undertow/ServletResourceProcessor.java b/undertow/deployment/src/main/java/org/jboss/shamrock/undertow/ServletResourceProcessor.java
index 564400417742d..eec18a4733fe4 100644
--- a/undertow/deployment/src/main/java/org/jboss/shamrock/undertow/ServletResourceProcessor.java
+++ b/undertow/deployment/src/main/java/org/jboss/shamrock/undertow/ServletResourceProcessor.java
@@ -65,6 +65,7 @@
 import org.jboss.shamrock.deployment.RuntimePriority;
 import org.jboss.shamrock.deployment.ShamrockConfig;
 import org.jboss.shamrock.deployment.codegen.BytecodeRecorder;
+import org.jboss.shamrock.runtime.ConfiguredValue;
 import org.jboss.shamrock.runtime.InjectionInstance;
 import org.jboss.shamrock.undertow.runtime.UndertowDeploymentTemplate;
 
@@ -207,7 +208,7 @@ public void process(ArchiveContext archiveContext, ProcessorContext processorCon
 
         try (BytecodeRecorder context = processorContext.addDeploymentTask(RuntimePriority.UNDERTOW_START)) {
             UndertowDeploymentTemplate template = context.getRecordingProxy(UndertowDeploymentTemplate.class);
-            template.startUndertow(null, null, config.getConfig("http.port", "8080"));
+            template.startUndertow(null, null, new ConfiguredValue("http.port", "8080"));
         }
     }
 
diff --git a/undertow/runtime/src/main/java/org/jboss/shamrock/undertow/runtime/UndertowDeploymentTemplate.java b/undertow/runtime/src/main/java/org/jboss/shamrock/undertow/runtime/UndertowDeploymentTemplate.java
index ad42757e607c0..7ac42316eb8b3 100644
--- a/undertow/runtime/src/main/java/org/jboss/shamrock/undertow/runtime/UndertowDeploymentTemplate.java
+++ b/undertow/runtime/src/main/java/org/jboss/shamrock/undertow/runtime/UndertowDeploymentTemplate.java
@@ -11,6 +11,7 @@
 import javax.servlet.Servlet;
 import javax.servlet.ServletException;
 
+import org.jboss.shamrock.runtime.ConfiguredValue;
 import org.jboss.shamrock.runtime.ContextObject;
 import org.jboss.shamrock.runtime.InjectionInstance;
 import org.jboss.shamrock.runtime.StartupContext;
@@ -124,12 +125,12 @@ public void addServletContextParameter(@ContextObject("deploymentInfo") Deployme
         info.addInitParameter(name, value);
     }
 
-    public void startUndertow(StartupContext startupContext, @ContextObject("servletHandler") HttpHandler handler, String port) throws ServletException {
+    public void startUndertow(StartupContext startupContext, @ContextObject("servletHandler") HttpHandler handler, ConfiguredValue port) throws ServletException {
         if (undertow == null) {
             try {
                 log.log(Level.INFO, "Starting Undertow on port " + port);
                 undertow = Undertow.builder()
-                      .addHttpListener(Integer.parseInt(port), "localhost")
+                      .addHttpListener(Integer.parseInt(port.getValue()), "localhost")
                       .setHandler(new CanonicalPathHandler(ROOT_HANDLER))
                       .build();
                 undertow.start();