diff --git a/config/config-mp/pom.xml b/config/config-mp/pom.xml
index 98090d26d..ca01905a3 100644
--- a/config/config-mp/pom.xml
+++ b/config/config-mp/pom.xml
@@ -61,4 +61,18 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <configuration>
+                    <environmentVariables>
+                        <FOO_BAR>mapped-env-value</FOO_BAR>
+                    </environmentVariables>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
 </project>
\ No newline at end of file
diff --git a/config/config-mp/src/main/java/io/helidon/config/mp/MpConfig.java b/config/config-mp/src/main/java/io/helidon/config/mp/MpConfig.java
index dd5ed279d..6a64e7189 100644
--- a/config/config-mp/src/main/java/io/helidon/config/mp/MpConfig.java
+++ b/config/config-mp/src/main/java/io/helidon/config/mp/MpConfig.java
@@ -16,11 +16,8 @@
 
 package io.helidon.config.mp;
 
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Optional;
-
 import io.helidon.config.ConfigSources;
+import io.helidon.config.OverrideSources;
 
 import org.eclipse.microprofile.config.Config;
 
@@ -49,30 +46,18 @@ public final class MpConfig {
             return (io.helidon.config.Config) mpConfig;
         }
 
-        io.helidon.config.Config.Builder builder = io.helidon.config.Config.builder()
+        io.helidon.config.Config mapper = io.helidon.config.Config.builder()
+                .sources(ConfigSources.empty())
+                .overrides(OverrideSources.empty())
                 .disableEnvironmentVariablesSource()
                 .disableSystemPropertiesSource()
+                .disableParserServices()
+                .disableFilterServices()
                 .disableCaching()
-                .disableParserServices();
-
-        if (mpConfig instanceof MpConfigImpl) {
-            ((MpConfigImpl) mpConfig).converters()
-                    .forEach((clazz, converter) -> {
-                        Class<Object> cl = (Class<Object>) clazz;
-                        builder.addStringMapper(cl, converter::convert);
-                    });
-        }
-
-        Map<String, String> allConfig = new HashMap<>();
-        mpConfig.getPropertyNames()
-                .forEach(it -> {
-                    // covering the condition where a config key disappears between getting the property names and requesting
-                    // the value
-                    Optional<String> optionalValue = mpConfig.getOptionalValue(it, String.class);
-                    optionalValue.ifPresent(value -> allConfig.put(it, value));
-                });
-
-        return builder.addSource(ConfigSources.create(allConfig))
+                .disableValueResolving()
+                .changesExecutor(command -> {})
                 .build();
+
+        return new SeConfig(mapper, mpConfig);
     }
 }
diff --git a/config/config-mp/src/main/java/io/helidon/config/mp/MpConfigProviderResolver.java b/config/config-mp/src/main/java/io/helidon/config/mp/MpConfigProviderResolver.java
index 3eb4245eb..9fb516b82 100644
--- a/config/config-mp/src/main/java/io/helidon/config/mp/MpConfigProviderResolver.java
+++ b/config/config-mp/src/main/java/io/helidon/config/mp/MpConfigProviderResolver.java
@@ -54,9 +54,12 @@ public class MpConfigProviderResolver extends ConfigProviderResolver {
     }
 
     @Override
-    public Config getConfig(ClassLoader loader) {
-        if (null == loader) {
-            loader = ClassLoader.getSystemClassLoader();
+    public Config getConfig(ClassLoader classLoader) {
+        ClassLoader loader;
+        if (classLoader == null) {
+            loader = Thread.currentThread().getContextClassLoader();
+        } else {
+            loader = classLoader;
         }
         Lock lock = RW_LOCK.readLock();
         try {
@@ -102,10 +105,17 @@ public class MpConfigProviderResolver extends ConfigProviderResolver {
 
     @Override
     public void registerConfig(Config config, ClassLoader classLoader) {
+        ClassLoader usedClassloader;
+        if (null == classLoader) {
+            usedClassloader = Thread.currentThread().getContextClassLoader();
+        } else {
+            usedClassloader = classLoader;
+        }
+
         Lock lock = RW_LOCK.writeLock();
         try {
             lock.lock();
-            doRegisterConfig(config, classLoader);
+            doRegisterConfig(config, usedClassloader);
         } finally {
             lock.unlock();
         }
diff --git a/config/config-mp/src/main/java/io/helidon/config/mp/SeConfig.java b/config/config-mp/src/main/java/io/helidon/config/mp/SeConfig.java
new file mode 100644
index 000000000..801fc8682
--- /dev/null
+++ b/config/config-mp/src/main/java/io/helidon/config/mp/SeConfig.java
@@ -0,0 +1,412 @@
+/*
+ * Copyright (c) 2020 Oracle and/or its affiliates.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.helidon.config.mp;
+
+import java.time.Instant;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.Function;
+import java.util.function.Predicate;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import io.helidon.common.GenericType;
+import io.helidon.config.Config;
+import io.helidon.config.ConfigMappingException;
+import io.helidon.config.ConfigValue;
+import io.helidon.config.ConfigValues;
+import io.helidon.config.MissingValueException;
+
+/**
+ * Implementation of SE config backed by MP config.
+ */
+class SeConfig implements Config {
+    private static final Pattern SPLIT_PATTERN = Pattern.compile("(?<!\\\\),");
+    private static final Pattern ESCAPED_COMMA_PATTERN = Pattern.compile("\\,", Pattern.LITERAL);
+
+    private final Map<Key, SeConfig> children = new ConcurrentHashMap<>();
+    private final io.helidon.config.Config mapper;
+    private final Key prefix;
+    private final Key key;
+    private final Key fullKey;
+    private final org.eclipse.microprofile.config.Config delegate;
+    private final MpConfigImpl delegateImpl;
+    private final String stringKey;
+    private final String stringPrefix;
+
+    SeConfig(io.helidon.config.Config mapper,
+             Key prefix,
+             Key key,
+             Key fullKey,
+             org.eclipse.microprofile.config.Config delegate,
+             MpConfigImpl delegateImpl) {
+        this.mapper = mapper;
+        this.prefix = prefix;
+        this.key = key;
+        this.fullKey = fullKey;
+        this.delegate = delegate;
+        this.stringKey = fullKey.toString();
+        this.stringPrefix = prefix.toString();
+        this.delegateImpl = delegateImpl;
+    }
+
+    SeConfig(io.helidon.config.Config mapper, org.eclipse.microprofile.config.Config delegate) {
+        this.mapper = mapper;
+        this.prefix = Key.create("");
+        this.key = prefix;
+        this.fullKey = prefix;
+        this.delegate = delegate;
+        this.stringKey = prefix.child(key).toString();
+        this.stringPrefix = prefix.toString();
+
+        if (delegate instanceof MpConfigImpl) {
+            this.delegateImpl = (MpConfigImpl) delegate;
+        } else {
+            this.delegateImpl = null;
+        }
+    }
+
+    @Override
+    public Instant timestamp() {
+        return Instant.now();
+    }
+
+    @Override
+    public Key key() {
+        return key;
+    }
+
+    @Override
+    public Config get(Key key) {
+        return children.computeIfAbsent(key, it -> new SeConfig(mapper, prefix, key, fullKey.child(key), delegate, delegateImpl));
+    }
+
+    @Override
+    public Config detach() {
+        return new SeConfig(mapper, fullKey, Key.create(""), fullKey, delegate, delegateImpl);
+    }
+
+    @Override
+    public Type type() {
+        // check if there are any sub-nodes that have prefix with our key
+        boolean isObject = false;
+
+        Iterator<String> it = delegate.getPropertyNames().iterator();
+        if (stringKey.isEmpty()) {
+            if (!it.hasNext()) {
+                return hasValue() ? Type.VALUE : Type.MISSING;
+            }
+            return Type.OBJECT;
+        }
+
+        while (it.hasNext()) {
+            String name = it.next();
+            if (name.equals(stringKey)) {
+                continue;
+            }
+            if (name.startsWith(stringKey + ".")) {
+                isObject = true;
+                break;
+            }
+        }
+        if (isObject) {
+            return Type.OBJECT;
+        }
+        if (hasValue()) {
+            return Type.VALUE;
+        }
+
+        return Type.MISSING;
+    }
+
+    @Override
+    public boolean hasValue() {
+        return currentValue().isPresent();
+    }
+
+    @Override
+    public Stream<Config> traverse(Predicate<Config> predicate) {
+        return asNodeList()
+                .map(list -> list.stream()
+                        .filter(predicate)
+                        .map(node -> traverseSubNodes(node, predicate))
+                        .reduce(Stream.empty(), Stream::concat))
+                .orElseThrow(MissingValueException.createSupplier(key()));
+
+    }
+
+    private Stream<Config> traverseSubNodes(Config config, Predicate<Config> predicate) {
+        if (config.type().isLeaf()) {
+            return Stream.of(config);
+        } else {
+            return config.asNodeList()
+                    .map(list -> list.stream()
+                            .filter(predicate)
+                            .map(node -> traverseSubNodes(node, predicate))
+                            .reduce(Stream.of(config), Stream::concat))
+                    .orElseThrow(MissingValueException.createSupplier(key()));
+        }
+    }
+
+    @Override
+    public <T> T convert(Class<T> type, String value) throws ConfigMappingException {
+        try {
+            return impl().findConverter(type)
+                    .convert(value);
+        } catch (Exception e) {
+            try {
+                return mapper.convert(type, value);
+            } catch (ConfigMappingException ignored) {
+                throw e;
+            }
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> ConfigValue<T> as(GenericType<T> genericType) {
+        if (genericType.isClass()) {
+            return (ConfigValue<T>) as(genericType.rawType());
+        }
+        throw new UnsupportedOperationException("MP Configuration does not support generic types.");
+    }
+
+    @Override
+    public <T> ConfigValue<T> as(Class<T> type) {
+        return delegate.getOptionalValue(stringKey, type)
+                .map(ConfigValues::simpleValue)
+                .orElseGet(ConfigValues::empty);
+    }
+
+    @Override
+    public <T> ConfigValue<T> as(Function<Config, T> mapper) {
+        if (type() == Type.MISSING) {
+            return ConfigValues.empty();
+        }
+
+        return ConfigValues.simpleValue(mapper.apply(this));
+    }
+
+    @Override
+    public <T> ConfigValue<List<T>> asList(Class<T> type) throws ConfigMappingException {
+        if (Config.class.equals(type)) {
+            return toNodeList();
+        }
+        return asList(stringKey, type)
+                .map(ConfigValues::simpleValue)
+                .orElseGet(ConfigValues::empty);
+    }
+
+    @Override
+    public <T> ConfigValue<List<T>> asList(Function<Config, T> mapper) throws ConfigMappingException {
+        return asNodeList()
+                .as(it -> it.stream()
+                        .map(mapper)
+                        .collect(Collectors.toList()));
+    }
+
+    @Override
+    public ConfigValue<List<Config>> asNodeList() throws ConfigMappingException {
+        return asList(Config.class);
+    }
+
+    @Override
+    public ConfigValue<Map<String, String>> asMap() throws MissingValueException {
+        Type nodeType = type();
+        if (nodeType == Type.MISSING || nodeType == Type.VALUE) {
+            return ConfigValues.empty();
+        }
+
+        Map<String, String> children = new HashMap<>();
+
+        for (String propertyName : delegate.getPropertyNames()) {
+            if (stringKey.isEmpty()) {
+                children.put(propertyName, delegate.getValue(propertyName, String.class));
+            } else {
+                if (propertyName.equals(stringKey)) {
+                    continue;
+                }
+                if (propertyName.startsWith(stringKey + ".")) {
+                    String noPrefix = propertyName.substring(stringPrefix.length() + 1);
+
+                    children.put(noPrefix, delegate.getValue(propertyName, String.class));
+                }
+            }
+        }
+
+        return ConfigValues.simpleValue(children);
+    }
+
+    @Override
+    public String toString() {
+        return type() + " " + stringKey + " = " + currentValue().orElse(null);
+    }
+
+    @SuppressWarnings("unchecked")
+    private <T> ConfigValue<List<T>> toNodeList() {
+        Type nodeType = type();
+        if (nodeType == Type.MISSING || nodeType == Type.VALUE) {
+            return ConfigValues.empty();
+        }
+
+        // this is an object or a list
+        List<T> result = new LinkedList<>();
+        Set<String> children = new HashSet<>();
+
+        for (String propertyName : delegate.getPropertyNames()) {
+            if (stringKey.isEmpty()) {
+                String noSuffix = propertyName;
+                int dot = noSuffix.indexOf('.');
+                if (dot > 0) {
+                    noSuffix = noSuffix.substring(0, dot);
+                }
+                children.add(noSuffix);
+            } else {
+                if (propertyName.equals(stringKey)) {
+                    continue;
+                }
+                if (propertyName.startsWith(stringKey + ".")) {
+                    String noSuffix = propertyName.substring(stringKey.length() + 1);
+                    int dot = noSuffix.indexOf('.');
+                    if (dot > 0) {
+                        noSuffix = noSuffix.substring(0, dot);
+                    }
+                    children.add(noSuffix);
+                }
+            }
+        }
+
+        for (String child : children) {
+            result.add((T) get(child));
+        }
+
+        return ConfigValues.simpleValue(result);
+    }
+
+    private Optional<String> currentValue() {
+        return delegate.getOptionalValue(stringKey, String.class);
+    }
+
+    private MpConfigImpl impl() {
+        if (null == delegateImpl) {
+            throw new IllegalStateException("Cannot convert to arbitrary types when the MP Config is not a Helidon "
+                                                    + "implementation");
+        }
+
+        return delegateImpl;
+    }
+
+    private <T> Optional<List<T>> asList(String configKey,
+                                         Class<T> typeArg) {
+        // first try to see if we have a direct value
+        Optional<String> optionalValue = delegate.getOptionalValue(configKey, String.class);
+        if (optionalValue.isPresent()) {
+            return Optional.of(toList(configKey, optionalValue.get(), typeArg));
+        }
+
+        /*
+         we also support indexed value
+         e.g. for key "my.list" you can have both:
+         my.list=12,13,14
+         or (not and):
+         my.list.0=12
+         my.list.1=13
+         */
+
+        String indexedConfigKey = configKey + ".0";
+        optionalValue = delegate.getOptionalValue(indexedConfigKey, String.class);
+        if (optionalValue.isPresent()) {
+            List<T> result = new LinkedList<>();
+
+            // first element is already in
+            result.add(convert(indexedConfigKey, optionalValue.get(), typeArg));
+
+            // hardcoded limit to lists of 1000 elements
+            for (int i = 1; i < 1000; i++) {
+                indexedConfigKey = configKey + "." + i;
+                optionalValue = delegate.getOptionalValue(indexedConfigKey, String.class);
+                if (optionalValue.isPresent()) {
+                    result.add(convert(indexedConfigKey, optionalValue.get(), typeArg));
+                } else {
+                    // finish the iteration on first missing index
+                    break;
+                }
+            }
+            return Optional.of(result);
+        } else {
+            return Optional.empty();
+        }
+    }
+
+    private <T> List<T> toList(String configKey,
+                               String stringValue,
+                               Class<T> typeArg) {
+        if (stringValue.isEmpty()) {
+            return List.of();
+        }
+        // we have a comma separated list
+        List<T> result = new LinkedList<>();
+        for (String value : toArray(stringValue)) {
+            result.add(convert(configKey, value, typeArg));
+        }
+        return result;
+    }
+
+    static String[] toArray(String stringValue) {
+        String[] values = SPLIT_PATTERN.split(stringValue, -1);
+
+        for (int i = 0; i < values.length; i++) {
+            String value = values[i];
+            values[i] = ESCAPED_COMMA_PATTERN.matcher(value).replaceAll(Matcher.quoteReplacement(","));
+        }
+        return values;
+    }
+
+    @SuppressWarnings("unchecked")
+    private <T> T convert(String key, String value, Class<T> type) {
+        if (null == value) {
+            return null;
+        }
+        if (String.class.equals(type)) {
+            return (T) value;
+        }
+
+        try {
+            return impl().getConverter(type)
+                    .orElseThrow(() -> new IllegalArgumentException("Did not find converter for type "
+                                                                            + type.getName()
+                                                                            + ", for key "
+                                                                            + key))
+                    .convert(value);
+        } catch (Exception e) {
+            try {
+                return mapper.convert(type, value);
+            } catch (ConfigMappingException ignored) {
+                throw e;
+            }
+        }
+    }
+}
diff --git a/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigReferenceTest.java b/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigReferenceTest.java
index bcc5b4428..57a5979fa 100644
--- a/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigReferenceTest.java
+++ b/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigReferenceTest.java
@@ -17,7 +17,7 @@
 package io.helidon.config.mp;
 
 import org.eclipse.microprofile.config.Config;
-import org.eclipse.microprofile.config.ConfigProvider;
+import org.eclipse.microprofile.config.spi.ConfigProviderResolver;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.Test;
 
@@ -35,7 +35,10 @@ public class MpConfigReferenceTest {
     static void initClass() {
         System.setProperty("value2", VALUE_2);
 
-        config = ConfigProvider.getConfig();
+        config = ConfigProviderResolver.instance()
+                .getBuilder()
+                .addDefaultSources()
+                .build();
     }
 
     @Test
diff --git a/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigTest.java b/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigTest.java
index 0df8a6742..bb173362a 100644
--- a/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigTest.java
+++ b/config/config-mp/src/test/java/io/helidon/config/mp/MpConfigTest.java
@@ -30,6 +30,7 @@ import io.helidon.config.spi.ConfigMapper;
 import io.helidon.config.spi.ConfigMapperProvider;
 
 import org.eclipse.microprofile.config.Config;
+import org.eclipse.microprofile.config.ConfigProvider;
 import org.eclipse.microprofile.config.spi.ConfigProviderResolver;
 import org.eclipse.microprofile.config.spi.ConfigSource;
 import org.junit.jupiter.api.BeforeAll;
@@ -274,5 +275,31 @@ public class MpConfigTest {
             counter.set(0);
         }
     }
+
+    @Test
+    void testEnvVar() {
+        ConfigProviderResolver instance = ConfigProviderResolver.instance();
+        ClassLoader myCl = Thread.currentThread().getContextClassLoader();
+        Config current = ConfigProvider.getConfig(myCl);
+
+        try {
+            instance.registerConfig(instance.getBuilder()
+                                            .withSources(MpConfigSources.environmentVariables())
+                                            .build(),
+                                    myCl);
+            Config myConfig = instance.getConfig(myCl);
+            // this must not throw an exception - path should be on any environment
+            // and the MP env var processing should make it available
+            String fooBar = myConfig.getValue("foo.bar", String.class);
+            assertThat(fooBar, is("mapped-env-value"));
+
+            io.helidon.config.Config helidonConfig = (io.helidon.config.Config) myConfig;
+            // should work if we use it as SE as well
+            fooBar = helidonConfig.get("foo.bar").asString().get();
+            assertThat(fooBar, is("mapped-env-value"));
+        } finally {
+            instance.registerConfig(current, myCl);
+        }
+    }
 }
 
diff --git a/config/config/src/main/java/io/helidon/config/BuilderImpl.java b/config/config/src/main/java/io/helidon/config/BuilderImpl.java
index ad7007235..cb50591d9 100644
--- a/config/config/src/main/java/io/helidon/config/BuilderImpl.java
+++ b/config/config/src/main/java/io/helidon/config/BuilderImpl.java
@@ -30,7 +30,6 @@ import java.util.concurrent.Executors;
 import java.util.function.BiFunction;
 import java.util.function.Function;
 import java.util.function.Supplier;
-import java.util.stream.Collectors;
 
 import io.helidon.common.GenericType;
 import io.helidon.common.Prioritized;
@@ -53,8 +52,6 @@ class BuilderImpl implements Config.Builder {
     /*
      * Config sources
      */
-    // sources to be sorted by priority
-    private final List<HelidonSourceWithPriority> prioritizedSources = new ArrayList<>();
     // sources "pre-sorted" - all user defined sources without priority will be ordered
     // as added, as well as config sources from meta configuration
     private final List<ConfigSource> sources = new LinkedList<>();
@@ -118,7 +115,6 @@ class BuilderImpl implements Config.Builder {
     public Config.Builder sources(List<Supplier<? extends ConfigSource>> sourceSuppliers) {
         // replace current config sources with the ones provided
         sources.clear();
-        prioritizedSources.clear();
 
         sourceSuppliers.stream()
                 .map(Supplier::get)
@@ -414,7 +410,7 @@ class BuilderImpl implements Config.Builder {
             envVarAliasGeneratorEnabled = true;
         }
 
-        boolean nothingConfigured = sources.isEmpty() && prioritizedSources.isEmpty();
+        boolean nothingConfigured = sources.isEmpty();
 
         if (nothingConfigured) {
             // use meta configuration to load all sources
@@ -429,29 +425,12 @@ class BuilderImpl implements Config.Builder {
             sources.stream()
                     .map(context::sourceRuntimeBase)
                     .forEach(targetSources::add);
-
-            // prioritized sources are next
-            targetSources.addAll(mergePrioritized(context));
         }
 
         // targetSources now contain runtimes correctly ordered for each config source
         return new ConfigSourcesRuntime(targetSources, mergingStrategy);
     }
 
-    private List<ConfigSourceRuntimeImpl> mergePrioritized(ConfigContextImpl context) {
-        List<PrioritizedConfigSource> allPrioritized = new ArrayList<>();
-        prioritizedSources.stream()
-                .map(it -> new PrioritizedConfigSource(it, context))
-                .forEach(allPrioritized::add);
-
-        Priorities.sort(allPrioritized);
-
-        return allPrioritized
-                .stream()
-                .map(it -> it.runtime(context))
-                .collect(Collectors.toList());
-    }
-
     @SuppressWarnings("ParameterNumber")
     ProviderImpl createProvider(ConfigMapperManager configMapperManager,
                                 ConfigSourcesRuntime targetConfigSource,
@@ -605,6 +584,7 @@ class BuilderImpl implements Config.Builder {
                 .disableSystemPropertiesSource()
                 .disableParserServices()
                 .disableFilterServices()
+                .changesExecutor(command -> {})
                 .build();
 
     }
diff --git a/messaging/messaging/src/main/java/io/helidon/messaging/ConnectorConfigHelper.java b/messaging/messaging/src/main/java/io/helidon/messaging/ConnectorConfigHelper.java
index 0e70a37d1..eaf3cf9ab 100644
--- a/messaging/messaging/src/main/java/io/helidon/messaging/ConnectorConfigHelper.java
+++ b/messaging/messaging/src/main/java/io/helidon/messaging/ConnectorConfigHelper.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c)  2020 Oracle and/or its affiliates.
+ * Copyright (c) 2020 Oracle and/or its affiliates.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -65,7 +65,7 @@ final class ConnectorConfigHelper {
         Config incomingChannelConfig = rootConfig.get("mp.messaging.incoming");
         Config outgoingChannelConfig = rootConfig.get("mp.messaging.outgoing");
 
-        Config channelsConfig = (Config) ConnectorConfigBuilder
+        Config channelsConfig = ConnectorConfigBuilder
                 .create(incomingChannelConfig)
                 .config(outgoingChannelConfig)
                 .build();
diff --git a/messaging/messaging/src/test/java/io/helidon/messaging/TestConfigurableConnector.java b/messaging/messaging/src/test/java/io/helidon/messaging/TestConfigurableConnector.java
index 737a470e8..d295fc4d5 100644
--- a/messaging/messaging/src/test/java/io/helidon/messaging/TestConfigurableConnector.java
+++ b/messaging/messaging/src/test/java/io/helidon/messaging/TestConfigurableConnector.java
@@ -17,9 +17,9 @@
 
 package io.helidon.messaging;
 
+import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
-import java.util.stream.Collectors;
 
 import io.helidon.config.mp.MpConfig;
 
@@ -56,17 +56,25 @@ public class TestConfigurableConnector implements IncomingConnectorFactory, Outg
 
     @Override
     public SubscriberBuilder<? extends Message<?>, Void> getSubscriberBuilder(final Config config) {
-        io.helidon.config.Config helidonConfig = MpConfig.toHelidonConfig(config);
-        printConfig(helidonConfig);
+        printConfig(config);
         return ReactiveStreams.<Message<CompletableFuture<Map<String, String>>>>builder()
                 .map(Message::getPayload)
-                .forEach(f -> f.complete(helidonConfig
-                        .traverse()
-                        .map(c -> Map.entry(c.key().name(), c.asString().get()))
-                        .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)))
-                );
+                .forEach(f -> f.complete(toMap(config)));
     }
 
+    private static Map<String, String> toMap(Config config) {
+        Map<String, String> result = new HashMap<>();
+
+        config.getPropertyNames()
+                .forEach(it -> {
+                    config.getOptionalValue(it, String.class).ifPresent(value -> result.put(it, value));
+                });
+
+        return result;
+    }
+    private static void printConfig(Config c) {
+        toMap(c).forEach((key, value) -> System.out.println(key + ": " + value));
+    }
     private static void printConfig(io.helidon.config.Config c) {
         c.asMap().orElse(Map.of()).forEach((key, value) -> System.out.println(key + ": " + value));
     }
diff --git a/microprofile/messaging/src/test/java/io/helidon/microprofile/messaging/AdHocConfigBuilderTest.java b/microprofile/messaging/src/test/java/io/helidon/microprofile/messaging/AdHocConfigBuilderTest.java
index 6088ea091..8df9dca43 100644
--- a/microprofile/messaging/src/test/java/io/helidon/microprofile/messaging/AdHocConfigBuilderTest.java
+++ b/microprofile/messaging/src/test/java/io/helidon/microprofile/messaging/AdHocConfigBuilderTest.java
@@ -21,12 +21,15 @@ import java.util.Map;
 
 import io.helidon.config.Config;
 import io.helidon.config.ConfigSources;
+import io.helidon.config.mp.MpConfigSources;
+
+import org.eclipse.microprofile.config.spi.ConfigProviderResolver;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
 
-import org.junit.jupiter.api.Test;
-
 class AdHocConfigBuilderTest {
 
     private static final String TEST_TOPIC_CONFIG = "TEST_TOPIC_CONFIG";
@@ -38,6 +41,38 @@ class AdHocConfigBuilderTest {
     private static final String ADDITION_ATTR_2_VALUE = "addition-attr2-value";
     private static final String TEST_CONNECTOR = "test-connector";
 
+    private static ConfigProviderResolver resolver;
+    private static ClassLoader cl;
+
+    @BeforeAll
+    static void initClass() {
+        resolver = ConfigProviderResolver.instance();
+        cl = Thread.currentThread().getContextClassLoader();
+    }
+
+    @Test
+    void currentContextMp() {
+        // MP tests ensure that the MP Config -> SE Config casting works as expected
+        // when obtained from config resolver
+        Map<String, String> propMap = Map.of(
+                "mp.messaging.outcoming.test-channel.key.serializer", AdHocConfigBuilderTest.class.getName()
+        );
+
+        resolver.registerConfig(resolver.getBuilder()
+                                        .withSources(MpConfigSources.create(propMap))
+                                        .build(), cl);
+
+        Config config = (Config) resolver.getConfig(cl);
+
+        org.eclipse.microprofile.config.Config c = AdHocConfigBuilder
+                .from(config.get("mp.messaging.outcoming.test-channel"))
+                .put(TEST_KEY, TEST_TOPIC_CUSTOM)
+                .build();
+
+        assertThat(c.getValue(TEST_KEY, String.class), is(TEST_TOPIC_CUSTOM));
+        assertThat(c.getValue("key.serializer", String.class), is(AdHocConfigBuilderTest.class.getName()));
+    }
+
     @Test
     void currentContext() {
         Map<String, String> propMap = Map.of(
@@ -57,6 +92,27 @@ class AdHocConfigBuilderTest {
         assertThat(c.getValue("key.serializer", String.class), is(AdHocConfigBuilderTest.class.getName()));
     }
 
+    @Test
+    void customValueOverrideMp() {
+        Map<String, String> propMap = Map.of(
+                "mp.messaging.outcoming.test-channel." + TEST_KEY, TEST_TOPIC_CONFIG,
+                "mp.messaging.outcoming.test-channel.key.serializer", AdHocConfigBuilderTest.class.getName()
+        );
+
+        resolver.registerConfig(resolver.getBuilder()
+                                        .withSources(MpConfigSources.create(propMap))
+                                        .build(), cl);
+
+        Config config = (Config) resolver.getConfig(cl);
+
+        org.eclipse.microprofile.config.Config c = AdHocConfigBuilder
+                .from(config.get("mp.messaging.outcoming.test-channel"))
+                .put(TEST_KEY, TEST_TOPIC_CUSTOM)
+                .build();
+
+        assertThat(c.getValue(TEST_KEY, String.class), is(TEST_TOPIC_CUSTOM));
+    }
+
     @Test
     void customValueOverride() {
         Map<String, String> propMap = Map.of(
@@ -76,6 +132,38 @@ class AdHocConfigBuilderTest {
         assertThat(c.getValue(TEST_KEY, String.class), is(TEST_TOPIC_CUSTOM));
     }
 
+    @Test
+    void putAllTestMp() {
+        Map<String, String> propMap = Map.of(
+                "mp.messaging.outcoming.test-channel." + TEST_KEY, TEST_TOPIC_CONFIG
+        );
+
+        Map<String, String> propMap2 = Map.of(
+                "mp.messaging.connector." + TEST_CONNECTOR + "." + ADDITION_ATTR_1, ADDITION_ATTR_1_VALUE,
+                "mp.messaging.connector." + TEST_CONNECTOR + "." + ADDITION_ATTR_2, ADDITION_ATTR_2_VALUE
+        );
+
+        resolver.registerConfig(resolver.getBuilder()
+                                        .withSources(MpConfigSources.create(propMap))
+                                        .build(), cl);
+
+        Config config = (Config) resolver.getConfig(cl);
+
+        resolver.registerConfig(resolver.getBuilder()
+                                        .withSources(MpConfigSources.create(propMap2))
+                                        .build(), cl);
+
+        Config config2 = (Config) resolver.getConfig(cl);
+
+        org.eclipse.microprofile.config.Config c = AdHocConfigBuilder
+                .from(config.get("mp.messaging.outcoming.test-channel"))
+                .putAll(config2.get("mp.messaging.connector." + TEST_CONNECTOR))
+                .build();
+
+        assertThat(c.getValue(ADDITION_ATTR_1, String.class), is(ADDITION_ATTR_1_VALUE));
+        assertThat(c.getValue(ADDITION_ATTR_2, String.class), is(ADDITION_ATTR_2_VALUE));
+    }
+
     @Test
     void putAllTest() {
         Map<String, String> propMap = Map.of(