rift-java

The official JVM SDK. Fluent typed DSL, all three transports, and JUnit 5, Spring and Testcontainers integrations.

Install 

<dependency>
  <groupId>io.github.achird-labs</groupId>
  <artifactId>rift-java-core</artifactId>
  <version>0.2.3</version>
  <scope>test</scope>
</dependency>

The BOM pins every module at once if you use more than one.

For the embedded transport, add rift-java-embedded (JDK 22+ bytecode, stable Panama FFM) or rift-java-embedded-jdk21 on JDK 21. Connect and spawn need neither and run on JDK 17+.

Hello world 

try (Rift rift = Rift.embedded()) {                  // or Rift.connect(uri) / Rift.spawn()
    Imposter users = rift.create(
        imposter("users").stub(onGet("/api/users/1").willReturn(okJson("{\"id\":1}"))));

    // point your system under test at users.uri(), then assert:
    users.verify(onGet("/api/users/1"), times(1));
}

Rift.embedded() runs the engine in-process over Panama FFM — no separate binary and no container. Rift.spawn() manages a downloaded binary for you, and Rift.connect(uri) targets any running admin endpoint.

Further reading