diff --git a/base/src/main/java/ai/javaclaw/configuration/ConfigurationManager.java b/base/src/main/java/ai/javaclaw/configuration/ConfigurationManager.java
index 884f4197..13166977 100644
--- a/base/src/main/java/ai/javaclaw/configuration/ConfigurationManager.java
+++ b/base/src/main/java/ai/javaclaw/configuration/ConfigurationManager.java
@@ -23,7 +23,7 @@ public class ConfigurationManager {
 
     public ConfigurationManager(Environment environment, ApplicationEventPublisher eventPublisher) {
         this.eventPublisher = eventPublisher;
-        this.configPath = resolveConfigPath(environment.getProperty("spring.allConfig.location"));
+        this.configPath = resolveConfigPath(environment.getProperty("spring.config.location"));
     }
 
     public void updateProperty(String key, Object value) throws IOException {
diff --git a/base/src/test/java/ai/javaclaw/configuration/ConfigurationManagerTest.java b/base/src/test/java/ai/javaclaw/configuration/ConfigurationManagerTest.java
new file mode 100644
index 00000000..b5b0e984
--- /dev/null
+++ b/base/src/test/java/ai/javaclaw/configuration/ConfigurationManagerTest.java
@@ -0,0 +1,150 @@
+package ai.javaclaw.configuration;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.mock.env.MockEnvironment;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ConfigurationManagerTest {
+
+    @TempDir
+    Path configDir;
+
+    private final List<Object> publishedEvents = new ArrayList<>();
+    private final ApplicationEventPublisher eventPublisher = publishedEvents::add;
+
+    private ConfigurationManager managerAt(String configLocation) {
+        MockEnvironment environment = new MockEnvironment();
+        if (configLocation != null) {
+            environment.setProperty("spring.config.location", configLocation);
+        }
+        return new ConfigurationManager(environment, eventPublisher);
+    }
+
+    // -----------------------------------------------------------------------
+    // spring.config.location is honoured when resolving the config file
+    //
+    // Every assertion below keys off MARKER, which only ever exists in the
+    // per-test temporary directory. Asserting on a property the real
+    // application.private.yaml also carries would let these tests pass by
+    // reading the fallback location instead of the configured one.
+    // -----------------------------------------------------------------------
+
+    private static final String MARKER = "javaclaw-configuration-manager-test";
+
+    private Path seedConfigFile(String fileName) throws IOException {
+        Path configFile = configDir.resolve(fileName);
+        Files.writeString(configFile, "marker: " + MARKER + "\n");
+        return configFile;
+    }
+
+    @Test
+    void readsFromTheLocationPointingAtAFile() throws IOException {
+        Path configFile = seedConfigFile("application.private.yaml");
+
+        Map<String, Object> config = managerAt(configFile.toString()).readApplicationYaml();
+
+        assertThat(config).containsEntry("marker", MARKER);
+    }
+
+    @Test
+    void readsFromTheLocationPointingAtADirectory() throws IOException {
+        seedConfigFile("application.private.yaml");
+
+        Map<String, Object> config = managerAt(configDir.toString()).readApplicationYaml();
+
+        assertThat(config).containsEntry("marker", MARKER);
+    }
+
+    @Test
+    void stripsTheFilePrefixFromTheLocation() throws IOException {
+        Path configFile = seedConfigFile("application.private.yaml");
+
+        Map<String, Object> config = managerAt("file:" + configFile).readApplicationYaml();
+
+        assertThat(config).containsEntry("marker", MARKER);
+    }
+
+    @Test
+    void usesTheFirstEntryOfACommaSeparatedLocationList() throws IOException {
+        Path configFile = seedConfigFile("application.private.yaml");
+
+        Map<String, Object> config = managerAt(configFile + ",classpath:/other.yaml").readApplicationYaml();
+
+        assertThat(config).containsEntry("marker", MARKER);
+    }
+
+    // -----------------------------------------------------------------------
+    // Writing goes to the same place reading does
+    // -----------------------------------------------------------------------
+
+    @Test
+    void writesToTheConfiguredLocation() throws IOException {
+        ConfigurationManager manager = managerAt(configDir.toString());
+
+        manager.updateProperty("agent.onboarding.completed", true);
+
+        Path written = configDir.resolve("application.private.yaml");
+        assertThat(written).exists();
+        assertThat(Files.readString(written)).contains("completed: true");
+    }
+
+    @Test
+    void writesNestedKeysWithoutDiscardingSiblings() throws IOException {
+        ConfigurationManager manager = managerAt(configDir.toString());
+
+        manager.updateProperty("spring.ai.model.chat", "ollama");
+        manager.updateProperty("spring.ai.ollama.chat.options.model", "gemma4:12b");
+
+        Map<String, Object> reloaded = manager.readApplicationYaml();
+        assertThat(reloaded).containsKey("spring");
+        String written = Files.readString(configDir.resolve("application.private.yaml"));
+        assertThat(written).contains("chat: ollama").contains("model: gemma4:12b");
+    }
+
+    @Test
+    void updatesSeveralPropertiesInASingleWrite() throws IOException {
+        ConfigurationManager manager = managerAt(configDir.toString());
+
+        manager.updateProperties(Map.of("agent.onboarding.completed", true, "spring.ai.model.chat", "ollama"));
+
+        String written = Files.readString(configDir.resolve("application.private.yaml"));
+        assertThat(written).contains("completed: true").contains("chat: ollama");
+        assertThat(publishedEvents).hasSize(1);
+    }
+
+    @Test
+    void publishesAConfigurationChangedEventOnEveryWrite() throws IOException {
+        ConfigurationManager manager = managerAt(configDir.toString());
+
+        manager.updateProperty("agent.onboarding.completed", true);
+
+        assertThat(publishedEvents).hasSize(1).allSatisfy(event ->
+                assertThat(event).isInstanceOf(ConfigurationChangedEvent.class));
+    }
+
+    // -----------------------------------------------------------------------
+    // First run, before any config file has been written
+    //
+    // This covers a configured location whose file does not exist yet. The
+    // separate branch where no location is configured at all resolves to a
+    // hardcoded path inside the source tree, so it cannot be asserted without
+    // writing there; it is left uncovered on purpose.
+    // -----------------------------------------------------------------------
+
+    @Test
+    void returnsAnEmptyConfigWhenTheConfiguredFileDoesNotExistYet() throws IOException {
+        Map<String, Object> config = managerAt(configDir.resolve("does-not-exist.yaml").toString()).readApplicationYaml();
+
+        assertThat(config).isEmpty();
+    }
+}