AWS Lambda + Kotlin + ZIP file: Java.lang.NoSuchMethodError

Question

GitHub Link

https://github.com/MarcoFaccani/aws-lambda-kotlin-zip-issue

Context

I have an AWS Lambda written in Kotlin and Maven using the AWS Java SDK V2 and Powertools by AWS for serialization. The lambda is invoked from the AWS API Gateway. I am packing the Lambda in a ZIP file using the methodology recommended by O'Reilly book Programming with AWS Lambda, which is to use the following plugins:

<!-- Shade -->
<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>${maven.shade.plugin.version}</version>
    <configuration>
        <createDependencyReducedPom>false</createDependencyReducedPom>
        <filters>
            <filter>
                <artifact>*:*</artifact>
                <excludes>
                    <!-- Suppress module-info.class warning-->
                    <exclude>module-info.class</exclude>
                </excludes>
            </filter>
        </filters>
    </configuration>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>shade</goal>
            </goals>
        </execution>
    </executions>
</plugin>

<!-- Recommended approach by O'Reilly Programming AWS Lambda book -->
<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>3.1.1</version>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>single</goal>
            </goals>
        </execution>
    </executions>
    <configuration>
        <appendAssemblyId>false</appendAssemblyId>
        <descriptors>
            <descriptor>src/assembly/lambda-zip.xml</descriptor>
        </descriptors>
        <finalName>lambda</finalName>
    </configuration>
</plugin>

<!-- Recommended approach by O'Reilly Programming AWS Lambda book -->
<plugin>
    <groupId>io.github.zlika</groupId>
    <artifactId>reproducible-build-maven-plugin</artifactId>
    <version>0.10</version>
    <executions>
        <execution>
            <phase>package</phase>
            <goals>
                <goal>strip-jar</goal>
            </goals>
        </execution>
    </executions>
</plugin>

The assembly file is as follows:

<assembly xmlns="http://maven.apache.org/ASSEMBLY/2.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.0.0
                      http://maven.apache.org/xsd/assembly-2.0.0.xsd">
  <id>lambda-zip</id>
  <formats>
    <format>zip</format>
  </formats>
  <includeBaseDirectory>false</includeBaseDirectory>
  <dependencySets>
    <dependencySet>
      <includes>
        <include>${project.groupId}:${project.artifactId}</include>
      </includes>
      <unpack>true</unpack>
      <unpackOptions>
        <excludes>
          <exclude>META-INF/MANIFEST.MF</exclude>
          <exclude>META-INF/maven/**</exclude>
        </excludes>
      </unpackOptions>
    </dependencySet>
    <dependencySet>
      <useProjectArtifact>false</useProjectArtifact>
      <unpack>false</unpack>
      <scope>runtime</scope>
      <outputDirectory>lib</outputDirectory>
    </dependencySet>
  </dependencySets>
</assembly>

Issue

When I run the Lambda, I get:

java.lang.NoSuchMethodError: 'com.fasterxml.jackson.core.JsonParser com.fasterxml.jackson.databind.ObjectMapper.createParser(java.lang.String)'

ZIP File Content

In the book, it exaplins that the zip file shall contain a /lib folder and within it all the JAR files of the dependencies used in the project. This is true but I also see the packages of each dependency in the root of the zip file (example com/fasterxml/jackson/databind containing all the compiled .class files) and I am wondering if this could be an issue or evidence that the packaging process isn't going as supposed.

Thank you in advance!