diff --git a/src/main/java/io/kurrent/dbclient/EventData.java b/src/main/java/io/kurrent/dbclient/EventData.java
index 3cd5ba4c..ee94fe96 100644
--- a/src/main/java/io/kurrent/dbclient/EventData.java
+++ b/src/main/java/io/kurrent/dbclient/EventData.java
@@ -55,30 +55,6 @@ public byte[] getUserMetadata() {
         return userMetadata;
     }
 
-    /**
-     * Configures an event data builder to host a JSON payload.
-     * @param eventType event's type.
-     * @param eventData event's payload.
-     * @return an event data builder.
-     * @param <A> a type that can be serialized in JSON.
-     */
-    @Deprecated
-    public static <A> EventDataBuilder builderAsJson(String eventType, A eventData) {
-        return builderAsJson(null, eventType, eventData);
-    }
-
-    /**
-     * Configures an event data builder to host a JSON payload.
-     * @param eventId event's id.
-     * @param eventType event's type.
-     * @param eventData event's payload.
-     * @return an event data builder.
-     * @param <A> a type that can be serialized in JSON.
-     */
-    public static <A> EventDataBuilder builderAsJson(UUID eventId, String eventType, A eventData) {
-        return EventDataBuilder.json(eventId, eventType, eventData);
-    }
-
     /**
      * Configures an event data builder to host a JSON payload.
      * @param eventType event's type.
diff --git a/src/main/java/io/kurrent/dbclient/EventDataBuilder.java b/src/main/java/io/kurrent/dbclient/EventDataBuilder.java
index 4de45daf..fde65402 100644
--- a/src/main/java/io/kurrent/dbclient/EventDataBuilder.java
+++ b/src/main/java/io/kurrent/dbclient/EventDataBuilder.java
@@ -17,35 +17,6 @@ public class EventDataBuilder {
 
     EventDataBuilder(){}
 
-    /**
-     * Configures builder to serialize event data as JSON.
-     * @param eventType event's type.
-     * @param eventData event's payload.
-     * @return an event data builder.
-     * @param <A> a type that can be serialized in JSON.
-     */
-    public static <A> EventDataBuilder json(String eventType, A eventData) {
-        return json(null, eventType, eventData);
-    }
-
-    /**
-     * Configures an event data builder to host a JSON payload.
-     * @param id event's id.
-     * @param eventType event's type.
-     * @param eventData event's payload.
-     * @return an event data builder.
-     * @param <A> a type that can be serialized in JSON.
-     */
-    @Deprecated
-    public static <A> EventDataBuilder json(UUID id, String eventType, A eventData) {
-        try {
-            JsonMapper mapper = new JsonMapper();
-            return json(id, eventType, mapper.writeValueAsBytes(eventData));
-        } catch (JsonProcessingException e) {
-            throw new RuntimeException(e);
-        }
-    }
-
     /**
      * Configures an event data builder to host a JSON payload.
      * @param eventType event's type.
@@ -115,22 +86,6 @@ public EventDataBuilder eventId(UUID id) {
         return this;
     }
 
-    /**
-     * Sets event's custom user metadata.
-     * @param <A> an object that can be serialized in JSON.
-     */
-    @Deprecated
-    public <A> EventDataBuilder metadataAsJson(A value) {
-        try {
-            JsonMapper mapper = new JsonMapper();
-            this.metadata = mapper.writeValueAsBytes(value);
-        } catch (JsonProcessingException e) {
-            throw new RuntimeException(e);
-        }
-
-        return this;
-    }
-
     /**
      * Sets event's custom user metadata.
      */
diff --git a/src/test/java/io/kurrent/dbclient/samples/appending_events/AppendingEvents.java b/src/test/java/io/kurrent/dbclient/samples/appending_events/AppendingEvents.java
index 01154920..856e8e83 100644
--- a/src/test/java/io/kurrent/dbclient/samples/appending_events/AppendingEvents.java
+++ b/src/test/java/io/kurrent/dbclient/samples/appending_events/AppendingEvents.java
@@ -1,22 +1,26 @@
 package io.kurrent.dbclient.samples.appending_events;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
 import io.kurrent.dbclient.*;
 import io.kurrent.dbclient.samples.TestEvent;
 
 import java.util.UUID;
 import java.util.concurrent.ExecutionException;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+
 public class AppendingEvents {
-    private static void appendToStream(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    private static void appendToStream(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
         // region append-to-stream
+        ObjectMapper objectMapper = new ObjectMapper();
+
         EventData eventData = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "some value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "some value"))
+                )
                 .build();
 
         AppendToStreamOptions options = AppendToStreamOptions.get()
@@ -27,16 +31,15 @@ private static void appendToStream(KurrentDBClient client) throws ExecutionExcep
         // endregion append-to-stream
     }
 
-    private static void appendWithSameId(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    private static void appendWithSameId(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
         // region append-duplicate-event
+        ObjectMapper objectMapper = new ObjectMapper();
+
         EventData eventData = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "some value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "some value")))
                 .build();
 
         AppendToStreamOptions options = AppendToStreamOptions.get()
@@ -51,26 +54,22 @@ private static void appendWithSameId(KurrentDBClient client) throws ExecutionExc
         // endregion append-duplicate-event
     }
 
-    private static void appendWithNoStream(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    private static void appendWithNoStream(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
         // region append-with-no-stream
+        ObjectMapper objectMapper = new ObjectMapper();
+
         EventData eventDataOne = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "some value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "some value")))
                 .build();
 
         EventData eventDataTwo = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "2",
-                                "some other value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("2", "some other value")))
                 .build();
 
         AppendToStreamOptions options = AppendToStreamOptions.get()
@@ -85,8 +84,9 @@ private static void appendWithNoStream(KurrentDBClient client) throws ExecutionE
         // endregion append-with-no-stream
     }
 
-    private static void appendWithConcurrencyCheck(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    private static void appendWithConcurrencyCheck(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
         // region append-with-concurrency-check
+        ObjectMapper objectMapper = new ObjectMapper();
 
         ReadStreamOptions readStreamOptions = ReadStreamOptions.get()
                 .forwards()
@@ -99,20 +99,14 @@ private static void appendWithConcurrencyCheck(KurrentDBClient client) throws Ex
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "clientOne"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "clientOne")))
                 .build();
 
         EventData clientTwoData = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "2",
-                                "clientTwo"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("2", "clientTwo")))
                 .build();
 
 
@@ -127,15 +121,14 @@ private static void appendWithConcurrencyCheck(KurrentDBClient client) throws Ex
         // endregion append-with-concurrency-check
     }
 
-    public void appendOverridingUserCredentials(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    public void appendOverridingUserCredentials(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
+        ObjectMapper objectMapper = new ObjectMapper();
+
         EventData eventData = EventData
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "some value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "some value")))
                 .build();
         //region overriding-user-credentials
         UserCredentials credentials = new UserCredentials("admin", "changeit");
diff --git a/src/test/java/io/kurrent/dbclient/samples/opentelemetry/Instrumentation.java b/src/test/java/io/kurrent/dbclient/samples/opentelemetry/Instrumentation.java
index c94d89f4..fc9c4f64 100644
--- a/src/test/java/io/kurrent/dbclient/samples/opentelemetry/Instrumentation.java
+++ b/src/test/java/io/kurrent/dbclient/samples/opentelemetry/Instrumentation.java
@@ -1,4 +1,5 @@
 package io.kurrent.dbclient.samples.opentelemetry;
+import org.testcontainers.shaded.com.fasterxml.jackson.core.JsonProcessingException;
 
 import io.kurrent.dbclient.*;
 import io.kurrent.dbclient.samples.TestEvent;
@@ -9,6 +10,7 @@
 import io.opentelemetry.sdk.resources.Resource;
 import io.opentelemetry.sdk.trace.SdkTracerProvider;
 import io.opentelemetry.sdk.trace.export.SimpleSpanProcessor;
+import org.testcontainers.shaded.com.fasterxml.jackson.databind.ObjectMapper;
 // endregion import-required-packages
 
 import java.util.UUID;
@@ -17,7 +19,9 @@
 import static io.opentelemetry.semconv.ServiceAttributes.SERVICE_NAME;
 
 public class Instrumentation {
-    private static void tracing(KurrentDBClient client) throws ExecutionException, InterruptedException {
+    private static void tracing(KurrentDBClient client) throws ExecutionException, InterruptedException, JsonProcessingException {
+        ObjectMapper objectMapper = new ObjectMapper();
+
         Resource resource = Resource.getDefault().toBuilder()
                 .put(SERVICE_NAME, "sample")
                 .build();
@@ -47,10 +51,7 @@ private static void tracing(KurrentDBClient client) throws ExecutionException, I
                 .builderAsJson(
                         UUID.randomUUID(),
                         "some-event",
-                        new TestEvent(
-                                "1",
-                                "some value"
-                        ))
+                        objectMapper.writeValueAsBytes(new TestEvent("1", "some value")))
                 .build();
         // endregion setup-client-for-tracing
 
diff --git a/src/test/java/io/kurrent/dbclient/streams/MetadataTests.java b/src/test/java/io/kurrent/dbclient/streams/MetadataTests.java
index cbacc8ac..3f81f9e1 100644
--- a/src/test/java/io/kurrent/dbclient/streams/MetadataTests.java
+++ b/src/test/java/io/kurrent/dbclient/streams/MetadataTests.java
@@ -27,7 +27,7 @@ default void testSetStreamMetadata() throws Throwable {
 
         metadata.setAcl(acl);
 
-        HashMap<String, Object> payload = new HashMap<>();
+        byte[] payload = "data".getBytes();
 
         String streamName = generateName();
 
@@ -43,7 +43,7 @@ default void testSetStreamMetadata() throws Throwable {
     default void testReadNoExistingMetadata() throws Throwable {
         KurrentDBClient client = getDatabase().defaultClient();
         String streamName = generateName();
-        client.appendToStream(streamName, EventDataBuilder.json("bar", new HashMap<String, Object>()).build()).get();
+        client.appendToStream(streamName, EventDataBuilder.json("bar", "data".getBytes()).build()).get();
 
         StreamMetadata got = client.getStreamMetadata(streamName).get();
 
@@ -54,7 +54,7 @@ default void testReadNoExistingMetadata() throws Throwable {
     default void testReadMetadataAfterStreamDeletion() throws Throwable {
         KurrentDBClient client = getDatabase().defaultClient();
         String streamName = generateName();
-        client.appendToStream(streamName, EventDataBuilder.json("bar", new HashMap<String, Object>()).build()).get();
+        client.appendToStream(streamName, EventDataBuilder.json("bar", "data".getBytes()).build()).get();
 
         client.deleteStream(streamName).get();
         client.getStreamMetadata(streamName).get();