diff --git a/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderLargeBatchesTest.java b/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderLargeBatchesTest.java
new file mode 100644
index 0000000..0e1adc5
--- /dev/null
+++ b/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderLargeBatchesTest.java
@@ -0,0 +1,130 @@
+package pl.tkowalcz.tjahzi.logback;
+
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.classic.joran.JoranConfigurator;
+import io.restassured.RestAssured;
+import io.restassured.http.ContentType;
+import io.restassured.parsing.Parser;
+import org.awaitility.Awaitility;
+import org.awaitility.Durations;
+import org.hamcrest.BaseMatcher;
+import org.hamcrest.Description;
+import org.junit.jupiter.api.Test;
+import org.slf4j.LoggerFactory;
+import org.testcontainers.containers.BindMode;
+import org.testcontainers.containers.GenericContainer;
+import org.testcontainers.containers.wait.strategy.Wait;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
+
+import java.net.URI;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+import static io.restassured.RestAssured.given;
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.hasItems;
+
+@Testcontainers
+class LokiAppenderLargeBatchesTest {
+
+    @Container
+    public GenericContainer loki = new GenericContainer("grafana/loki:latest")
+            .withCommand("-config.file=/etc/loki-config.yaml")
+            .withClasspathResourceMapping("loki-config.yaml",
+                    "/etc/loki-config.yaml",
+                    BindMode.READ_ONLY)
+            .waitingFor(
+                    Wait.forHttp("/ready")
+                            .forPort(3100)
+            )
+            .withExposedPorts(3100);
+
+    @Test
+    void shouldSendData() throws Exception {
+        // Given
+        System.setProperty("loki.host", loki.getHost());
+        System.setProperty("loki.port", loki.getFirstMappedPort().toString());
+
+        URI uri = getClass()
+                .getClassLoader()
+                .getResource("appender-test-large-batches.xml")
+                .toURI();
+
+        LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
+
+        JoranConfigurator configurator = new JoranConfigurator();
+        configurator.setContext(context);
+
+        context.reset();
+        configurator.doConfigure(uri.toURL());
+
+        String expectedLogLine = "Cupcake ipsum dolor sit amet cake wafer. " +
+                "Souffle jelly beans biscuit topping. " +
+                "Danish bonbon gummies powder caramels. " +
+                "Danish jelly beans sweet roll topping jelly beans oat cake toffee. " +
+                "Chocolate cake sesame snaps brownie biscuit cheesecake. " +
+                "Ice cream dessert sweet donut marshmallow. " +
+                "Muffin bear claw cookie jelly-o sugar plum jelly beans apple pie fruitcake cookie. " +
+                "Tootsie roll carrot cake pastry jujubes jelly beans chupa chups. " +
+                "Souffle cake muffin liquorice tart souffle pie sesame snaps.";
+
+        long expectedTimestamp = System.currentTimeMillis();
+        Logger logger = context.getLogger(LokiAppenderLargeBatchesTest.class);
+
+        // When
+        for (int i = 0; i < 1000; i++) {
+            logger.info(i + " " + expectedLogLine);
+        }
+
+        // Then
+        RestAssured.port = loki.getFirstMappedPort();
+        RestAssured.baseURI = "http://" + loki.getHost();
+        RestAssured.registerParser("text/plain", Parser.JSON);
+
+        Awaitility
+                .await()
+                .atMost(Durations.ONE_MINUTE)
+                .pollInterval(Durations.ONE_SECOND)
+                .ignoreExceptions()
+                .untilAsserted(() -> {
+                    given()
+                            .contentType(ContentType.URLENC)
+                            .urlEncodingEnabled(false)
+                            .formParam("&start=" + expectedTimestamp + "&limit=1000&query=%7Bserver%3D%22127.0.0.1%22%7D")
+                            .when()
+                            .get("/loki/api/v1/query_range")
+                            .then()
+                            .log()
+                            .all()
+                            .statusCode(200)
+                            .body("status", equalTo("success"))
+                            .body("data.result.size()", equalTo(1))
+                            .body("data.result[0].stream.server", equalTo("127.0.0.1"))
+                            .body("data.result[0].values.size()", equalTo(1000))
+                            .body("data.result[0].values", hasItems(new BaseMatcher<>() {
+                                                                        @Override
+                                                                        public boolean matches(Object o) {
+                                                                            List<Object> list = (List<Object>) o;
+                                                                            if (list.size() != 2) {
+                                                                                return false;
+                                                                            }
+
+                                                                            long actualTimestamp = Long.parseLong(list.get(0).toString());
+                                                                            String actualLogLine = list.get(1).toString();
+
+                                                                            return actualLogLine.contains(expectedLogLine)
+                                                                                    && (expectedTimestamp - actualTimestamp) < TimeUnit.MINUTES.toMillis(1);
+                                                                        }
+
+                                                                        @Override
+                                                                        public void describeTo(Description description) {
+
+                                                                        }
+                                                                    }
+
+                            ));
+                });
+    }
+}
diff --git a/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderTest.java b/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderTest.java
index 61c6c87..0e6dd65 100644
--- a/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderTest.java
+++ b/logback-appender/src/test/java/pl/tkowalcz/tjahzi/logback/LokiAppenderTest.java
@@ -2,7 +2,6 @@ package pl.tkowalcz.tjahzi.logback;
 
 import ch.qos.logback.classic.LoggerContext;
 import ch.qos.logback.classic.joran.JoranConfigurator;
-import ch.qos.logback.core.joran.spi.JoranException;
 import io.restassured.RestAssured;
 import io.restassured.http.ContentType;
 import io.restassured.parsing.Parser;
@@ -19,9 +18,7 @@ import org.testcontainers.containers.wait.strategy.Wait;
 import org.testcontainers.junit.jupiter.Container;
 import org.testcontainers.junit.jupiter.Testcontainers;
 
-import java.net.MalformedURLException;
 import java.net.URI;
-import java.net.URISyntaxException;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
@@ -45,14 +42,14 @@ class LokiAppenderTest {
             .withExposedPorts(3100);
 
     @Test
-    void shouldSendData() throws URISyntaxException, MalformedURLException, JoranException {
+    void shouldSendData() throws Exception {
         // Given
         System.setProperty("loki.host", loki.getHost());
         System.setProperty("loki.port", loki.getFirstMappedPort().toString());
 
         URI uri = getClass()
                 .getClassLoader()
-                .getResource("logback-configuration.xml")
+                .getResource("basic-appender-test-configuration.xml")
                 .toURI();
 
         LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
diff --git a/logback-appender/src/test/resources/appender-test-large-batches.xml b/logback-appender/src/test/resources/appender-test-large-batches.xml
new file mode 100644
index 0000000..6d87c8e
--- /dev/null
+++ b/logback-appender/src/test/resources/appender-test-large-batches.xml
@@ -0,0 +1,29 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+
+        <bufferSizeMegabytes>2</bufferSizeMegabytes>
+        <batchWait>10000</batchWait>
+        <batchSize>1048576</batchSize>
+
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>
diff --git a/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-set-to-64.xml b/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-set-to-64.xml
new file mode 100644
index 0000000..6296203
--- /dev/null
+++ b/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-set-to-64.xml
@@ -0,0 +1,27 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+
+        <bufferSizeMegabytes>64</bufferSizeMegabytes>
+
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>
diff --git a/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-unset.xml b/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-unset.xml
new file mode 100644
index 0000000..6e9255b
--- /dev/null
+++ b/logback-appender/src/test/resources/appender-test-with-buffer-size-megabytes-unset.xml
@@ -0,0 +1,24 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>
diff --git a/logback-appender/src/test/resources/appender-test-with-log-label-set.xml b/logback-appender/src/test/resources/appender-test-with-log-label-set.xml
new file mode 100644
index 0000000..917af93
--- /dev/null
+++ b/logback-appender/src/test/resources/appender-test-with-log-label-set.xml
@@ -0,0 +1,28 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+
+        <logLevelLabel>
+            log_level
+        </logLevelLabel>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>
diff --git a/logback-appender/src/test/resources/appender-test-with-log-label-unset.xml b/logback-appender/src/test/resources/appender-test-with-log-label-unset.xml
new file mode 100644
index 0000000..6e9255b
--- /dev/null
+++ b/logback-appender/src/test/resources/appender-test-with-log-label-unset.xml
@@ -0,0 +1,24 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>
diff --git a/logback-appender/src/test/resources/basic-appender-test-configuration.xml b/logback-appender/src/test/resources/basic-appender-test-configuration.xml
new file mode 100644
index 0000000..6e9255b
--- /dev/null
+++ b/logback-appender/src/test/resources/basic-appender-test-configuration.xml
@@ -0,0 +1,24 @@
+<configuration debug="true">
+    <appender name="Loki" class="pl.tkowalcz.tjahzi.logback.LokiAppender">
+        <host>${loki.host}</host>
+        <port>${loki.port}</port>
+
+        <encoder>
+            <pattern>%-4relative [%thread] %-5level %logger{35} - %msg%n</pattern>
+        </encoder>
+
+        <header>
+            <name>X-Org-Id</name>
+            <value>Circus</value>
+        </header>
+
+        <label>
+            <name>server</name>
+            <value>127.0.0.1</value>
+        </label>
+    </appender>
+
+    <root level="debug">
+        <appender-ref ref="Loki"/>
+    </root>
+</configuration>