Maven 4 Arrives After 15 Years: A Complete Rewrite of the Java Build Tool

Maven 3 has been unchanged since its 2010 release, accumulating a large amount of historical debt. Maven 4 is a bottom‑up rewrite that focuses on four directions: splitting the POM model, rewriting performance, adapting to modern Java, and upgrading developer experience. It remains fully compatible with the Maven 3 ecosystem while delivering higher capability, speed, and reliability.

Core architecture change – Build POM vs Consumer POM

In Maven 3 a single POM mixed build configuration and dependency metadata, leading to pollution, redundancy, and transitive‑dependency confusion. Maven 4 separates these concerns into two models:

Build POM (modelVersion 4.1.0) – used for local development and CI builds. It contains full configuration: plugins, profiles, build logic, directories.

Consumer POM (modelVersion 4.0.0) – used when publishing to a repository. It contains only minimal metadata (GAV, dependencyManagement, transitive dependencies).

Example of the model version change:

<modelVersion>4.0.0</modelVersion>
<groupId>com.demo</groupId>
<artifactId>my-app</artifactId>
<version>1.0.0</version>
<!-- Build config + dependency metadata mixed together -->
<build>...</build>
<dependencies>...</dependencies>

After migration to Maven 4 (Build POM 4.1.0):

<modelVersion>4.1.0<!-- new version --></modelVersion>
<groupId>com.demo</groupId>
<artifactId>my-app</artifactId>
<version>${revision}<!-- dynamic version --></version>
<!-- Full build config, visible only locally -->
<build>...</build>
<dependencies>...</dependencies>

Performance revolution

The parallel build engine has been completely rewritten. Benchmarks on a large project show substantial gains:

4‑thread build: 5m48s (Maven 3) → 3m22s (Maven 4) – 42 % faster

8‑thread build: 4m55s (Maven 3) → 2m38s (Maven 4) – 46 % faster

Cache hit rate: 62 % → 85 % – +23 %

Dependency I/O reads/writes: 15k/8.9k → 8.5k/5.4k – -44 % / -39 %

Additional improvements include incremental build & resume (failed builds can continue without a full rebuild), a smart cache based on file fingerprints and dependency‑tree verification, and a >30 % speedup in dependency resolution.

POM syntax & multi‑module

Automatic sub‑project discovery – no need to declare <modules> manually.

Atomic deployment – a failing sub‑module does not block others.

Version inheritance – parent version can be omitted and is automatically inherited.

Example of automatic module discovery (Maven 3 required explicit declaration):

<modules>
  <module>user-service</module>
  <module>order-service</module>
  <module>pay-service</module>
</modules>

Native BOM packaging type

<packaging>bom<!-- native type --></packaging>
<dependencyManagement>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-boot-dependencies</artifactId>
    <version>3.2.0</version>
    <scope>import</scope>
  </dependency>
</dependencyManagement>

Unified sources model

<sources>
  <source>
    <scope>main</scope>
    <directory>src/main/java</directory>
  </source>
  <source>
    <scope>main</scope>
    <directory>src/generated/java</directory>
  </source>
  <source>
    <scope>test</scope>
    <directory>src/test/java</directory>
  </source>
</sources>

Dynamic versioning (native ${revision})

<properties>
  <revision>2.1.0</revision>
</properties>
<version>${revision}</version>

JPMS (Java Platform Module System) support

Baseline JDK 17+ (projects can still compile for JDK 8/11).

Two new packaging types without plugins: classpath-jar – traditional non‑modular JAR. modular-jar – explicit module JAR containing module-info.java.

<packaging>modular-jar</packaging>
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <version>3.13.0</version>
      <configuration>
        <release>17</release>
        <modular>true</modular>
      </configuration>
    </plugin>
  </plugins>
</build>

Security & credential management

New password encryption supporting command‑line and external vault integration.

Dependency checksum verification (SHA‑256) to prevent tampering.

Settings 5.0 introduces a new XML schema.

Migration tool & compatibility

The official mvnup tool checks compatibility, lists deprecated APIs, and can automatically upgrade POMs to version 4.1.0:

mvnup check   # check compatibility, list deprecated APIs
mvnup apply   # automatically upgrade POM to 4.1.0

99 % of Maven 3 plugins work without modification.

Maven 4 itself requires JDK 17+, while project code can continue to target JDK 8/11.

Core feature comparison (Maven 3 vs Maven 4)

Runtime JDK : Maven 3 – JDK 7+; Maven 4 – JDK 17+.

POM model : Maven 3 – single 4.0.0 model; Maven 4 – Build (4.1.0) + Consumer (4.0.0).

Multi‑module : Maven 3 – manual <modules>; Maven 4 – automatic sub‑project discovery.

Parallel build : Maven 3 – unstable, noisy logs; Maven 4 – rewritten engine, 50 %+ speedup.

BOM support : Maven 3 – pom packaging + plugin; Maven 4 – native bom packaging.

Dynamic version : Maven 3 – requires flatten plugin; Maven 4 – native ${revision}.

JPMS : Maven 3 – plugin adaptation; Maven 4 – native modular-jar.

Incremental build : Maven 3 – basic support; Maven 4 – resume, smart cache.

Consumer POM : Maven 3 – none (full publish); Maven 4 – automatic slimming, no redundancy.

Source directories : Maven 3 – single directory; Maven 4 – multiple directories via unified sources.

Lifecycle : Maven 3 – fixed; Maven 4 – new hooks before:all / each.