diff --git a/CHANGELOG.md b/CHANGELOG.md
index a3428d1..c0c6c2a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,12 @@ The envelope wire format is versioned separately by `meta.schema_version`
 
 ## [Unreleased]
 
+## [1.3.1] - 2026-10-26
+
+### Changed
+
+- The poison `dead_letter` block is now built by core `PoisonRecord.build(body, originalQueue, attempts, error, exception)` (babelqueue-core 1.14.0) instead of by hand; the DLQ record is byte-for-byte unchanged (`reason: "poison"`, `failed_at`, `lang: "java"`).
+
 ## [1.3.0] - 2026-10-26
 
 MINOR (ADR-0037 decision 1). The envelope stays at `schema_version: 1`.
diff --git a/pom.xml b/pom.xml
index 40dbe6d..cb60bbf 100644
--- a/pom.xml
+++ b/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>com.babelqueue</groupId>
     <artifactId>babelqueue-pulsar</artifactId>
-    <version>1.3.0</version>
+    <version>1.3.1</version>
     <packaging>jar</packaging>
 
     <name>BabelQueue Apache Pulsar</name>
@@ -49,7 +49,7 @@
         <maven.compiler.release>17</maven.compiler.release>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-        <babelqueue-core.version>1.13.0</babelqueue-core.version>
+        <babelqueue-core.version>1.14.0</babelqueue-core.version>
         <pulsar.version>3.3.5</pulsar.version>
         <junit.version>5.10.3</junit.version>
         <mockito.version>5.12.0</mockito.version>
diff --git a/src/main/java/com/babelqueue/pulsar/PulsarConsumer.java b/src/main/java/com/babelqueue/pulsar/PulsarConsumer.java
index d3ca2cb..8285d0f 100644
--- a/src/main/java/com/babelqueue/pulsar/PulsarConsumer.java
+++ b/src/main/java/com/babelqueue/pulsar/PulsarConsumer.java
@@ -4,7 +4,6 @@
 import com.babelqueue.DeadLetters;
 import com.babelqueue.Envelope;
 import com.babelqueue.EnvelopeCodec;
-import com.babelqueue.JsonValues;
 import com.babelqueue.PoisonRecord;
 import com.babelqueue.UnknownUrnException;
 import java.nio.ByteBuffer;
@@ -312,15 +311,8 @@ private void routePoison(Message<byte[]> message, Envelope partial, byte[] body,
         }
         byte[] record;
         try {
-            Map<String, Object> block = new LinkedHashMap<>();
-            block.put("reason", "poison");
-            block.put("error", cause.getMessage());
-            block.put("exception", cause.getClass().getName());
-            block.put("failed_at", System.currentTimeMillis());
-            block.put("original_queue", queueName(message));
-            block.put("attempts", reconciled);
-            block.put("lang", EnvelopeCodec.SOURCE_LANG);
-            record = PoisonRecord.build(body, JsonValues.encode(block)).getBytes(StandardCharsets.UTF_8);
+            record = PoisonRecord.build(body, queueName(message), reconciled, cause.getMessage(),
+                cause.getClass().getName()).getBytes(StandardCharsets.UTF_8);
         } catch (RuntimeException error) {
             leaveUnsettled(message, partial, error);
             return;